Deny access to overly-permissive IPC objects #41
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Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
It can make sense to disable this to reduce attack surface / complexity.
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
Signed-off-by: Daniel Micay <[email protected]>
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Commit f5ce815 ("scsi: target: tcmu: Support DATA_BLOCK_SIZE = N * PAGE_SIZE") introduced xas_next() calls to iterate xarray elements. These calls triggered the WARNING "suspicious RCU usage" at tcmu device set up [1]. In the call stack of xas_next(), xas_load() was called. According to its comment, this function requires "the xa_lock or the RCU lock". To avoid the warning: - Guard the small loop calling xas_next() in tcmu_get_empty_block with RCU lock. - In the large loop in tcmu_copy_data using RCU lock would possibly disable preemtion for a long time (copy multi MBs). Therefore replace XA_STATE, xas_set and xas_next with a single xa_load. [1] [ 1899.867091] ============================= [ 1899.871199] WARNING: suspicious RCU usage [ 1899.875310] 5.13.0-rc1+ #41 Not tainted [ 1899.879222] ----------------------------- [ 1899.883299] include/linux/xarray.h:1182 suspicious rcu_dereference_check() usage! [ 1899.890940] other info that might help us debug this: [ 1899.899082] rcu_scheduler_active = 2, debug_locks = 1 [ 1899.905719] 3 locks held by kworker/0:1/1368: [ 1899.910161] #0: ffffa1f8c8b98738 ((wq_completion)target_submission){+.+.}-{0:0}, at: process_one_work+0x1ee/0x580 [ 1899.920732] #1: ffffbd7040cd7e78 ((work_completion)(&q->sq.work)){+.+.}-{0:0}, at: process_one_work+0x1ee/0x580 [ 1899.931146] #2: ffffa1f8d1c99768 (&udev->cmdr_lock){+.+.}-{3:3}, at: tcmu_queue_cmd+0xea/0x160 [target_core_user] [ 1899.941678] stack backtrace: [ 1899.946093] CPU: 0 PID: 1368 Comm: kworker/0:1 Not tainted 5.13.0-rc1+ #41 [ 1899.953070] Hardware name: System manufacturer System Product Name/PRIME Z270-A, BIOS 1302 03/15/2018 [ 1899.962459] Workqueue: target_submission target_queued_submit_work [target_core_mod] [ 1899.970337] Call Trace: [ 1899.972839] dump_stack+0x6d/0x89 [ 1899.976222] xas_descend+0x10e/0x120 [ 1899.979875] xas_load+0x39/0x50 [ 1899.983077] tcmu_get_empty_blocks+0x115/0x1c0 [target_core_user] [ 1899.989318] queue_cmd_ring+0x1da/0x630 [target_core_user] [ 1899.994897] ? rcu_read_lock_sched_held+0x3f/0x70 [ 1899.999695] ? trace_kmalloc+0xa6/0xd0 [ 1900.003501] ? __kmalloc+0x205/0x380 [ 1900.007167] tcmu_queue_cmd+0x12f/0x160 [target_core_user] [ 1900.012746] __target_execute_cmd+0x23/0xa0 [target_core_mod] [ 1900.018589] transport_generic_new_cmd+0x1f3/0x370 [target_core_mod] [ 1900.025046] transport_handle_cdb_direct+0x34/0x50 [target_core_mod] [ 1900.031517] target_queued_submit_work+0x43/0xe0 [target_core_mod] [ 1900.037837] process_one_work+0x268/0x580 [ 1900.041952] ? process_one_work+0x580/0x580 [ 1900.046195] worker_thread+0x55/0x3b0 [ 1900.049921] ? process_one_work+0x580/0x580 [ 1900.054192] kthread+0x143/0x160 [ 1900.057499] ? kthread_create_worker_on_cpu+0x40/0x40 [ 1900.062661] ret_from_fork+0x1f/0x30 Link: https://lore.kernel.org/r/[email protected] Fixes: f5ce815 ("scsi: target: tcmu: Support DATA_BLOCK_SIZE = N * PAGE_SIZE") Reported-by: Shin'ichiro Kawasaki <[email protected]> Tested-by: Shin'ichiro Kawasaki <[email protected]> Signed-off-by: Bodo Stroesser <[email protected]> Signed-off-by: Martin K. Petersen <[email protected]>
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Oct 12, 2022
[ Upstream commit 2b7aa91 ] NULL pointer dereference is triggered when calling thp split via debugfs on the system with offlined memory blocks. With debug option enabled, the following kernel messages are printed out: page:00000000467f4890 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x121c000 flags: 0x17fffc00000000(node=0|zone=2|lastcpupid=0x1ffff) raw: 0017fffc00000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 page dumped because: unmovable page page:000000007d7ab72e is uninitialized and poisoned page dumped because: VM_BUG_ON_PAGE(PagePoisoned(p)) ------------[ cut here ]------------ kernel BUG at include/linux/mm.h:1248! invalid opcode: 0000 [#1] PREEMPT SMP PTI CPU: 16 PID: 20964 Comm: bash Tainted: G I 6.0.0-rc3-foll-numa+ #41 ... RIP: 0010:split_huge_pages_write+0xcf4/0xe30 This shows that page_to_nid() in page_zone() is unexpectedly called for an offlined memmap. Use pfn_to_online_page() to get struct page in PFN walker. Link: https://lkml.kernel.org/r/[email protected] Fixes: f1dd2cd ("mm, memory_hotplug: do not associate hotadded memory to zones until online") [visible after d0dc12e] Signed-off-by: Naoya Horiguchi <[email protected]> Co-developed-by: David Hildenbrand <[email protected]> Signed-off-by: David Hildenbrand <[email protected]> Reviewed-by: Yang Shi <[email protected]> Acked-by: Michal Hocko <[email protected]> Reviewed-by: Miaohe Lin <[email protected]> Reviewed-by: Oscar Salvador <[email protected]> Acked-by: Kirill A. Shutemov <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Muchun Song <[email protected]> Cc: <[email protected]> [5.10+] Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…>cur_tx [ Upstream commit c1c0ce3 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll [r8169] / rtl8169_start_xmit [r8169] write (marked) to 0xffff888102474b74 of 4 bytes by task 5358 on cpu 29: rtl8169_start_xmit (drivers/net/ethernet/realtek/r8169_main.c:4254) r8169 dev_hard_start_xmit (./include/linux/netdevice.h:4889 ./include/linux/netdevice.h:4903 net/core/dev.c:3544 net/core/dev.c:3560) sch_direct_xmit (net/sched/sch_generic.c:342) __dev_queue_xmit (net/core/dev.c:3817 net/core/dev.c:4306) ip_finish_output2 (./include/linux/netdevice.h:3082 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv4/ip_output.c:233) __ip_finish_output (net/ipv4/ip_output.c:311 net/ipv4/ip_output.c:293) ip_finish_output (net/ipv4/ip_output.c:328) ip_output (net/ipv4/ip_output.c:435) ip_send_skb (./include/net/dst.h:458 net/ipv4/ip_output.c:127 net/ipv4/ip_output.c:1486) udp_send_skb (net/ipv4/udp.c:963) udp_sendmsg (net/ipv4/udp.c:1246) inet_sendmsg (net/ipv4/af_inet.c:840 (discriminator 4)) sock_sendmsg (net/socket.c:730 net/socket.c:753) __sys_sendto (net/socket.c:2177) __x64_sys_sendto (net/socket.c:2185) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) read to 0xffff888102474b74 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4397 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) common_interrupt (arch/x86/kernel/irq.c:247 (discriminator 14)) asm_common_interrupt (./arch/x86/include/asm/idtentry.h:636) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x002f4815 -> 0x002f4816 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The write side of drivers/net/ethernet/realtek/r8169_main.c is: ================== 4251 /* rtl_tx needs to see descriptor changes before updated tp->cur_tx */ 4252 smp_wmb(); 4253 → 4254 WRITE_ONCE(tp->cur_tx, tp->cur_tx + frags + 1); 4255 4256 stop_queue = !netif_subqueue_maybe_stop(dev, 0, rtl_tx_slots_avail(tp), 4257 R8169_TX_STOP_THRS, 4258 R8169_TX_START_THRS); The read side is the function rtl_tx(): 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ → 4397 if (tp->cur_tx != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } Obviously from the code, an earlier detected data-race for tp->cur_tx was fixed in the line 4363: 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { but the same solution is required for protecting the other access to tp->cur_tx: → 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); The write in the line 4254 is protected with WRITE_ONCE(), but the read in the line 4397 might have suffered read tearing under some compiler optimisations. The fix eliminated the KCSAN data-race report for this bug. It is yet to be evaluated what happens if tp->cur_tx changes between the test in line 4363 and line 4397. This test should certainly not be cached by the compiler in some register for such a long time, while asynchronous writes to tp->cur_tx might have occurred in line 4254 in the meantime. Fixes: 94d8a98 ("r8169: reduce number of workaround doorbell rings") Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…cArray[entry].opts1 [ Upstream commit dcf75a0 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 race at unknown origin, with read to 0xffff888140d37570 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0xb0000042 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The read side is in drivers/net/ethernet/realtek/r8169_main.c ========================================= 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 → 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } tp->TxDescArray[entry].opts1 is reported to have a data-race and READ_ONCE() fixes this KCSAN warning. 4366 → 4367 status = le32_to_cpu(READ_ONCE(tp->TxDescArray[entry].opts1)); 4368 if (status & DescOwn) 4369 break; 4370 Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Fixes: 1da177e ("Linux-2.6.12-rc2") Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…>opts1 [ Upstream commit f97eee4 ] KCSAN reported the following data-race bug: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 race at unknown origin, with read to 0xffff888117e43510 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x80003fff -> 0x3402805f Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== drivers/net/ethernet/realtek/r8169_main.c: ========================================== 4429 → 4430 status = le32_to_cpu(desc->opts1); 4431 if (status & DescOwn) 4432 break; 4433 4434 /* This barrier is needed to keep us from reading 4435 * any other fields out of the Rx descriptor until 4436 * we know the status of DescOwn 4437 */ 4438 dma_rmb(); 4439 4440 if (unlikely(status & RxRES)) { 4441 if (net_ratelimit()) 4442 netdev_warn(dev, "Rx ERROR. status = %08x\n", Marco Elver explained that dma_rmb() doesn't prevent the compiler to tear up the access to desc->opts1 which can be written to concurrently. READ_ONCE() should prevent that from happening: 4429 → 4430 status = le32_to_cpu(READ_ONCE(desc->opts1)); 4431 if (status & DescOwn) 4432 break; 4433 As the consequence of this fix, this KCSAN warning was eliminated. Fixes: 6202806 ("r8169: drop member opts1_mask from struct rtl8169_private") Suggested-by: Marco Elver <[email protected]> Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Nov 2, 2023
…>cur_tx [ Upstream commit c1c0ce3 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll [r8169] / rtl8169_start_xmit [r8169] write (marked) to 0xffff888102474b74 of 4 bytes by task 5358 on cpu 29: rtl8169_start_xmit (drivers/net/ethernet/realtek/r8169_main.c:4254) r8169 dev_hard_start_xmit (./include/linux/netdevice.h:4889 ./include/linux/netdevice.h:4903 net/core/dev.c:3544 net/core/dev.c:3560) sch_direct_xmit (net/sched/sch_generic.c:342) __dev_queue_xmit (net/core/dev.c:3817 net/core/dev.c:4306) ip_finish_output2 (./include/linux/netdevice.h:3082 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv4/ip_output.c:233) __ip_finish_output (net/ipv4/ip_output.c:311 net/ipv4/ip_output.c:293) ip_finish_output (net/ipv4/ip_output.c:328) ip_output (net/ipv4/ip_output.c:435) ip_send_skb (./include/net/dst.h:458 net/ipv4/ip_output.c:127 net/ipv4/ip_output.c:1486) udp_send_skb (net/ipv4/udp.c:963) udp_sendmsg (net/ipv4/udp.c:1246) inet_sendmsg (net/ipv4/af_inet.c:840 (discriminator 4)) sock_sendmsg (net/socket.c:730 net/socket.c:753) __sys_sendto (net/socket.c:2177) __x64_sys_sendto (net/socket.c:2185) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) read to 0xffff888102474b74 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4397 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) common_interrupt (arch/x86/kernel/irq.c:247 (discriminator 14)) asm_common_interrupt (./arch/x86/include/asm/idtentry.h:636) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x002f4815 -> 0x002f4816 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The write side of drivers/net/ethernet/realtek/r8169_main.c is: ================== 4251 /* rtl_tx needs to see descriptor changes before updated tp->cur_tx */ 4252 smp_wmb(); 4253 → 4254 WRITE_ONCE(tp->cur_tx, tp->cur_tx + frags + 1); 4255 4256 stop_queue = !netif_subqueue_maybe_stop(dev, 0, rtl_tx_slots_avail(tp), 4257 R8169_TX_STOP_THRS, 4258 R8169_TX_START_THRS); The read side is the function rtl_tx(): 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ → 4397 if (tp->cur_tx != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } Obviously from the code, an earlier detected data-race for tp->cur_tx was fixed in the line 4363: 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { but the same solution is required for protecting the other access to tp->cur_tx: → 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); The write in the line 4254 is protected with WRITE_ONCE(), but the read in the line 4397 might have suffered read tearing under some compiler optimisations. The fix eliminated the KCSAN data-race report for this bug. It is yet to be evaluated what happens if tp->cur_tx changes between the test in line 4363 and line 4397. This test should certainly not be cached by the compiler in some register for such a long time, while asynchronous writes to tp->cur_tx might have occurred in line 4254 in the meantime. Fixes: 94d8a98 ("r8169: reduce number of workaround doorbell rings") Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…cArray[entry].opts1 [ Upstream commit dcf75a0 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 race at unknown origin, with read to 0xffff888140d37570 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0xb0000042 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The read side is in drivers/net/ethernet/realtek/r8169_main.c ========================================= 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 → 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } tp->TxDescArray[entry].opts1 is reported to have a data-race and READ_ONCE() fixes this KCSAN warning. 4366 → 4367 status = le32_to_cpu(READ_ONCE(tp->TxDescArray[entry].opts1)); 4368 if (status & DescOwn) 4369 break; 4370 Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Fixes: 1da177e ("Linux-2.6.12-rc2") Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…>opts1 [ Upstream commit f97eee4 ] KCSAN reported the following data-race bug: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 race at unknown origin, with read to 0xffff888117e43510 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x80003fff -> 0x3402805f Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== drivers/net/ethernet/realtek/r8169_main.c: ========================================== 4429 → 4430 status = le32_to_cpu(desc->opts1); 4431 if (status & DescOwn) 4432 break; 4433 4434 /* This barrier is needed to keep us from reading 4435 * any other fields out of the Rx descriptor until 4436 * we know the status of DescOwn 4437 */ 4438 dma_rmb(); 4439 4440 if (unlikely(status & RxRES)) { 4441 if (net_ratelimit()) 4442 netdev_warn(dev, "Rx ERROR. status = %08x\n", Marco Elver explained that dma_rmb() doesn't prevent the compiler to tear up the access to desc->opts1 which can be written to concurrently. READ_ONCE() should prevent that from happening: 4429 → 4430 status = le32_to_cpu(READ_ONCE(desc->opts1)); 4431 if (status & DescOwn) 4432 break; 4433 As the consequence of this fix, this KCSAN warning was eliminated. Fixes: 6202806 ("r8169: drop member opts1_mask from struct rtl8169_private") Suggested-by: Marco Elver <[email protected]> Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Nov 16, 2023
…cArray[entry].opts1 [ Upstream commit dcf75a0 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 race at unknown origin, with read to 0xffff888140d37570 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0xb0000042 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The read side is in drivers/net/ethernet/realtek/r8169_main.c ========================================= 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 → 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } tp->TxDescArray[entry].opts1 is reported to have a data-race and READ_ONCE() fixes this KCSAN warning. 4366 → 4367 status = le32_to_cpu(READ_ONCE(tp->TxDescArray[entry].opts1)); 4368 if (status & DescOwn) 4369 break; 4370 Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Fixes: 1da177e ("Linux-2.6.12-rc2") Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…>opts1 [ Upstream commit f97eee4 ] KCSAN reported the following data-race bug: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 race at unknown origin, with read to 0xffff888117e43510 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x80003fff -> 0x3402805f Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== drivers/net/ethernet/realtek/r8169_main.c: ========================================== 4429 → 4430 status = le32_to_cpu(desc->opts1); 4431 if (status & DescOwn) 4432 break; 4433 4434 /* This barrier is needed to keep us from reading 4435 * any other fields out of the Rx descriptor until 4436 * we know the status of DescOwn 4437 */ 4438 dma_rmb(); 4439 4440 if (unlikely(status & RxRES)) { 4441 if (net_ratelimit()) 4442 netdev_warn(dev, "Rx ERROR. status = %08x\n", Marco Elver explained that dma_rmb() doesn't prevent the compiler to tear up the access to desc->opts1 which can be written to concurrently. READ_ONCE() should prevent that from happening: 4429 → 4430 status = le32_to_cpu(READ_ONCE(desc->opts1)); 4431 if (status & DescOwn) 4432 break; 4433 As the consequence of this fix, this KCSAN warning was eliminated. Fixes: 6202806 ("r8169: drop member opts1_mask from struct rtl8169_private") Suggested-by: Marco Elver <[email protected]> Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Nov 16, 2023
…cArray[entry].opts1 [ Upstream commit dcf75a0 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 race at unknown origin, with read to 0xffff888140d37570 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0xb0000042 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The read side is in drivers/net/ethernet/realtek/r8169_main.c ========================================= 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 → 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } tp->TxDescArray[entry].opts1 is reported to have a data-race and READ_ONCE() fixes this KCSAN warning. 4366 → 4367 status = le32_to_cpu(READ_ONCE(tp->TxDescArray[entry].opts1)); 4368 if (status & DescOwn) 4369 break; 4370 Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Fixes: 1da177e ("Linux-2.6.12-rc2") Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Nov 16, 2023
…>opts1 [ Upstream commit f97eee4 ] KCSAN reported the following data-race bug: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 race at unknown origin, with read to 0xffff888117e43510 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x80003fff -> 0x3402805f Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== drivers/net/ethernet/realtek/r8169_main.c: ========================================== 4429 → 4430 status = le32_to_cpu(desc->opts1); 4431 if (status & DescOwn) 4432 break; 4433 4434 /* This barrier is needed to keep us from reading 4435 * any other fields out of the Rx descriptor until 4436 * we know the status of DescOwn 4437 */ 4438 dma_rmb(); 4439 4440 if (unlikely(status & RxRES)) { 4441 if (net_ratelimit()) 4442 netdev_warn(dev, "Rx ERROR. status = %08x\n", Marco Elver explained that dma_rmb() doesn't prevent the compiler to tear up the access to desc->opts1 which can be written to concurrently. READ_ONCE() should prevent that from happening: 4429 → 4430 status = le32_to_cpu(READ_ONCE(desc->opts1)); 4431 if (status & DescOwn) 4432 break; 4433 As the consequence of this fix, this KCSAN warning was eliminated. Fixes: 6202806 ("r8169: drop member opts1_mask from struct rtl8169_private") Suggested-by: Marco Elver <[email protected]> Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…cArray[entry].opts1 [ Upstream commit dcf75a0 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 race at unknown origin, with read to 0xffff888140d37570 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0xb0000042 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The read side is in drivers/net/ethernet/realtek/r8169_main.c ========================================= 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 → 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } tp->TxDescArray[entry].opts1 is reported to have a data-race and READ_ONCE() fixes this KCSAN warning. 4366 → 4367 status = le32_to_cpu(READ_ONCE(tp->TxDescArray[entry].opts1)); 4368 if (status & DescOwn) 4369 break; 4370 Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Fixes: 1da177e ("Linux-2.6.12-rc2") Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…>opts1 [ Upstream commit f97eee4 ] KCSAN reported the following data-race bug: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 race at unknown origin, with read to 0xffff888117e43510 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x80003fff -> 0x3402805f Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== drivers/net/ethernet/realtek/r8169_main.c: ========================================== 4429 → 4430 status = le32_to_cpu(desc->opts1); 4431 if (status & DescOwn) 4432 break; 4433 4434 /* This barrier is needed to keep us from reading 4435 * any other fields out of the Rx descriptor until 4436 * we know the status of DescOwn 4437 */ 4438 dma_rmb(); 4439 4440 if (unlikely(status & RxRES)) { 4441 if (net_ratelimit()) 4442 netdev_warn(dev, "Rx ERROR. status = %08x\n", Marco Elver explained that dma_rmb() doesn't prevent the compiler to tear up the access to desc->opts1 which can be written to concurrently. READ_ONCE() should prevent that from happening: 4429 → 4430 status = le32_to_cpu(READ_ONCE(desc->opts1)); 4431 if (status & DescOwn) 4432 break; 4433 As the consequence of this fix, this KCSAN warning was eliminated. Fixes: 6202806 ("r8169: drop member opts1_mask from struct rtl8169_private") Suggested-by: Marco Elver <[email protected]> Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…>cur_tx [ Upstream commit c1c0ce3 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll [r8169] / rtl8169_start_xmit [r8169] write (marked) to 0xffff888102474b74 of 4 bytes by task 5358 on cpu 29: rtl8169_start_xmit (drivers/net/ethernet/realtek/r8169_main.c:4254) r8169 dev_hard_start_xmit (./include/linux/netdevice.h:4889 ./include/linux/netdevice.h:4903 net/core/dev.c:3544 net/core/dev.c:3560) sch_direct_xmit (net/sched/sch_generic.c:342) __dev_queue_xmit (net/core/dev.c:3817 net/core/dev.c:4306) ip_finish_output2 (./include/linux/netdevice.h:3082 ./include/net/neighbour.h:526 ./include/net/neighbour.h:540 net/ipv4/ip_output.c:233) __ip_finish_output (net/ipv4/ip_output.c:311 net/ipv4/ip_output.c:293) ip_finish_output (net/ipv4/ip_output.c:328) ip_output (net/ipv4/ip_output.c:435) ip_send_skb (./include/net/dst.h:458 net/ipv4/ip_output.c:127 net/ipv4/ip_output.c:1486) udp_send_skb (net/ipv4/udp.c:963) udp_sendmsg (net/ipv4/udp.c:1246) inet_sendmsg (net/ipv4/af_inet.c:840 (discriminator 4)) sock_sendmsg (net/socket.c:730 net/socket.c:753) __sys_sendto (net/socket.c:2177) __x64_sys_sendto (net/socket.c:2185) do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:120) read to 0xffff888102474b74 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4397 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) common_interrupt (arch/x86/kernel/irq.c:247 (discriminator 14)) asm_common_interrupt (./arch/x86/include/asm/idtentry.h:636) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x002f4815 -> 0x002f4816 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The write side of drivers/net/ethernet/realtek/r8169_main.c is: ================== 4251 /* rtl_tx needs to see descriptor changes before updated tp->cur_tx */ 4252 smp_wmb(); 4253 → 4254 WRITE_ONCE(tp->cur_tx, tp->cur_tx + frags + 1); 4255 4256 stop_queue = !netif_subqueue_maybe_stop(dev, 0, rtl_tx_slots_avail(tp), 4257 R8169_TX_STOP_THRS, 4258 R8169_TX_START_THRS); The read side is the function rtl_tx(): 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ → 4397 if (tp->cur_tx != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } Obviously from the code, an earlier detected data-race for tp->cur_tx was fixed in the line 4363: 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { but the same solution is required for protecting the other access to tp->cur_tx: → 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); The write in the line 4254 is protected with WRITE_ONCE(), but the read in the line 4397 might have suffered read tearing under some compiler optimisations. The fix eliminated the KCSAN data-race report for this bug. It is yet to be evaluated what happens if tp->cur_tx changes between the test in line 4363 and line 4397. This test should certainly not be cached by the compiler in some register for such a long time, while asynchronous writes to tp->cur_tx might have occurred in line 4254 in the meantime. Fixes: 94d8a98 ("r8169: reduce number of workaround doorbell rings") Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Nov 16, 2023
…cArray[entry].opts1 [ Upstream commit dcf75a0 ] KCSAN reported the following data-race: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 race at unknown origin, with read to 0xffff888140d37570 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4368 drivers/net/ethernet/realtek/r8169_main.c:4581) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0xb0000042 -> 0x00000000 Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== The read side is in drivers/net/ethernet/realtek/r8169_main.c ========================================= 4355 static void rtl_tx(struct net_device *dev, struct rtl8169_private *tp, 4356 int budget) 4357 { 4358 unsigned int dirty_tx, bytes_compl = 0, pkts_compl = 0; 4359 struct sk_buff *skb; 4360 4361 dirty_tx = tp->dirty_tx; 4362 4363 while (READ_ONCE(tp->cur_tx) != dirty_tx) { 4364 unsigned int entry = dirty_tx % NUM_TX_DESC; 4365 u32 status; 4366 → 4367 status = le32_to_cpu(tp->TxDescArray[entry].opts1); 4368 if (status & DescOwn) 4369 break; 4370 4371 skb = tp->tx_skb[entry].skb; 4372 rtl8169_unmap_tx_skb(tp, entry); 4373 4374 if (skb) { 4375 pkts_compl++; 4376 bytes_compl += skb->len; 4377 napi_consume_skb(skb, budget); 4378 } 4379 dirty_tx++; 4380 } 4381 4382 if (tp->dirty_tx != dirty_tx) { 4383 dev_sw_netstats_tx_add(dev, pkts_compl, bytes_compl); 4384 WRITE_ONCE(tp->dirty_tx, dirty_tx); 4385 4386 netif_subqueue_completed_wake(dev, 0, pkts_compl, bytes_compl, 4387 rtl_tx_slots_avail(tp), 4388 R8169_TX_START_THRS); 4389 /* 4390 * 8168 hack: TxPoll requests are lost when the Tx packets are 4391 * too close. Let's kick an extra TxPoll request when a burst 4392 * of start_xmit activity is detected (if it is not detected, 4393 * it is slow enough). -- FR 4394 * If skb is NULL then we come here again once a tx irq is 4395 * triggered after the last fragment is marked transmitted. 4396 */ 4397 if (READ_ONCE(tp->cur_tx) != dirty_tx && skb) 4398 rtl8169_doorbell(tp); 4399 } 4400 } tp->TxDescArray[entry].opts1 is reported to have a data-race and READ_ONCE() fixes this KCSAN warning. 4366 → 4367 status = le32_to_cpu(READ_ONCE(tp->TxDescArray[entry].opts1)); 4368 if (status & DescOwn) 4369 break; 4370 Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: Marco Elver <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Fixes: 1da177e ("Linux-2.6.12-rc2") Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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…>opts1 [ Upstream commit f97eee4 ] KCSAN reported the following data-race bug: ================================================================== BUG: KCSAN: data-race in rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 race at unknown origin, with read to 0xffff888117e43510 of 4 bytes by interrupt on cpu 21: rtl8169_poll (drivers/net/ethernet/realtek/r8169_main.c:4430 drivers/net/ethernet/realtek/r8169_main.c:4583) r8169 __napi_poll (net/core/dev.c:6527) net_rx_action (net/core/dev.c:6596 net/core/dev.c:6727) __do_softirq (kernel/softirq.c:553) __irq_exit_rcu (kernel/softirq.c:427 kernel/softirq.c:632) irq_exit_rcu (kernel/softirq.c:647) sysvec_apic_timer_interrupt (arch/x86/kernel/apic/apic.c:1074 (discriminator 14)) asm_sysvec_apic_timer_interrupt (./arch/x86/include/asm/idtentry.h:645) cpuidle_enter_state (drivers/cpuidle/cpuidle.c:291) cpuidle_enter (drivers/cpuidle/cpuidle.c:390) call_cpuidle (kernel/sched/idle.c:135) do_idle (kernel/sched/idle.c:219 kernel/sched/idle.c:282) cpu_startup_entry (kernel/sched/idle.c:378 (discriminator 1)) start_secondary (arch/x86/kernel/smpboot.c:210 arch/x86/kernel/smpboot.c:294) secondary_startup_64_no_verify (arch/x86/kernel/head_64.S:433) value changed: 0x80003fff -> 0x3402805f Reported by Kernel Concurrency Sanitizer on: CPU: 21 PID: 0 Comm: swapper/21 Tainted: G L 6.6.0-rc2-kcsan-00143-gb5cbe7c00aa0 #41 Hardware name: ASRock X670E PG Lightning/X670E PG Lightning, BIOS 1.21 04/26/2023 ================================================================== drivers/net/ethernet/realtek/r8169_main.c: ========================================== 4429 → 4430 status = le32_to_cpu(desc->opts1); 4431 if (status & DescOwn) 4432 break; 4433 4434 /* This barrier is needed to keep us from reading 4435 * any other fields out of the Rx descriptor until 4436 * we know the status of DescOwn 4437 */ 4438 dma_rmb(); 4439 4440 if (unlikely(status & RxRES)) { 4441 if (net_ratelimit()) 4442 netdev_warn(dev, "Rx ERROR. status = %08x\n", Marco Elver explained that dma_rmb() doesn't prevent the compiler to tear up the access to desc->opts1 which can be written to concurrently. READ_ONCE() should prevent that from happening: 4429 → 4430 status = le32_to_cpu(READ_ONCE(desc->opts1)); 4431 if (status & DescOwn) 4432 break; 4433 As the consequence of this fix, this KCSAN warning was eliminated. Fixes: 6202806 ("r8169: drop member opts1_mask from struct rtl8169_private") Suggested-by: Marco Elver <[email protected]> Cc: Heiner Kallweit <[email protected]> Cc: [email protected] Cc: "David S. Miller" <[email protected]> Cc: Eric Dumazet <[email protected]> Cc: Jakub Kicinski <[email protected]> Cc: Paolo Abeni <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/lkml/[email protected]/ Signed-off-by: Mirsad Goran Todorovac <[email protected]> Acked-by: Marco Elver <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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[ Upstream commit 19468ed ] The cgroup1_hierarchy test uses setup_classid_environment to setup cgroupv1 environment. The problem is that the environment is set in /sys/fs/cgroup and therefore, if not run under an own mount namespace, effectively deletes all system cgroups: $ ls /sys/fs/cgroup | wc -l 27 $ sudo ./test_progs -t cgroup1_hierarchy #41/1 cgroup1_hierarchy/test_cgroup1_hierarchy:OK #41/2 cgroup1_hierarchy/test_root_cgid:OK #41/3 cgroup1_hierarchy/test_invalid_level:OK #41/4 cgroup1_hierarchy/test_invalid_cgid:OK #41/5 cgroup1_hierarchy/test_invalid_hid:OK #41/6 cgroup1_hierarchy/test_invalid_cgrp_name:OK #41/7 cgroup1_hierarchy/test_invalid_cgrp_name2:OK #41/8 cgroup1_hierarchy/test_sleepable_prog:OK #41 cgroup1_hierarchy:OK Summary: 1/8 PASSED, 0 SKIPPED, 0 FAILED $ ls /sys/fs/cgroup | wc -l 1 To avoid this, run setup_cgroup_environment first which will create an own mount namespace. This only affects the cgroupv1_hierarchy test as all other cgroup1 test progs already run setup_cgroup_environment prior to running setup_classid_environment. Also add a comment to the header of setup_classid_environment to warn against this invalid usage in future. Fixes: 3607692 ("selftests/bpf: Add selftests for cgroup1 hierarchy") Signed-off-by: Viktor Malik <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected] Signed-off-by: Sasha Levin <[email protected]>
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Jun 1, 2024
[ Upstream commit 19468ed ] The cgroup1_hierarchy test uses setup_classid_environment to setup cgroupv1 environment. The problem is that the environment is set in /sys/fs/cgroup and therefore, if not run under an own mount namespace, effectively deletes all system cgroups: $ ls /sys/fs/cgroup | wc -l 27 $ sudo ./test_progs -t cgroup1_hierarchy #41/1 cgroup1_hierarchy/test_cgroup1_hierarchy:OK #41/2 cgroup1_hierarchy/test_root_cgid:OK #41/3 cgroup1_hierarchy/test_invalid_level:OK #41/4 cgroup1_hierarchy/test_invalid_cgid:OK #41/5 cgroup1_hierarchy/test_invalid_hid:OK #41/6 cgroup1_hierarchy/test_invalid_cgrp_name:OK #41/7 cgroup1_hierarchy/test_invalid_cgrp_name2:OK #41/8 cgroup1_hierarchy/test_sleepable_prog:OK #41 cgroup1_hierarchy:OK Summary: 1/8 PASSED, 0 SKIPPED, 0 FAILED $ ls /sys/fs/cgroup | wc -l 1 To avoid this, run setup_cgroup_environment first which will create an own mount namespace. This only affects the cgroupv1_hierarchy test as all other cgroup1 test progs already run setup_cgroup_environment prior to running setup_classid_environment. Also add a comment to the header of setup_classid_environment to warn against this invalid usage in future. Fixes: 3607692 ("selftests/bpf: Add selftests for cgroup1 hierarchy") Signed-off-by: Viktor Malik <[email protected]> Signed-off-by: Andrii Nakryiko <[email protected]> Link: https://lore.kernel.org/bpf/[email protected] Signed-off-by: Sasha Levin <[email protected]>
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Aug 23, 2024
[ Upstream commit ecbf607 ] Fixes a hang thats triggered when MPV is run on a DCN401 dGPU: mpv --hwdec=vaapi --vo=gpu --hwdec-codecs=all and then enabling fullscreen playback (double click on the video) The following calltrace will be seen: [ 181.843989] BUG: kernel NULL pointer dereference, address: 0000000000000000 [ 181.843997] #PF: supervisor instruction fetch in kernel mode [ 181.844003] #PF: error_code(0x0010) - not-present page [ 181.844009] PGD 0 P4D 0 [ 181.844020] Oops: 0010 [#1] PREEMPT SMP NOPTI [ 181.844028] CPU: 6 PID: 1892 Comm: gnome-shell Tainted: G W OE 6.5.0-41-generic #41~22.04.2-Ubuntu [ 181.844038] Hardware name: System manufacturer System Product Name/CROSSHAIR VI HERO, BIOS 6302 10/23/2018 [ 181.844044] RIP: 0010:0x0 [ 181.844079] Code: Unable to access opcode bytes at 0xffffffffffffffd6. [ 181.844084] RSP: 0018:ffffb593c2b8f7b0 EFLAGS: 00010246 [ 181.844093] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000004 [ 181.844099] RDX: ffffb593c2b8f804 RSI: ffffb593c2b8f7e0 RDI: ffff9e3c8e758400 [ 181.844105] RBP: ffffb593c2b8f7b8 R08: ffffb593c2b8f9c8 R09: ffffb593c2b8f96c [ 181.844110] R10: 0000000000000000 R11: 0000000000000000 R12: ffffb593c2b8f9c8 [ 181.844115] R13: 0000000000000001 R14: ffff9e3c88000000 R15: 0000000000000005 [ 181.844121] FS: 00007c6e323bb5c0(0000) GS:ffff9e3f85f80000(0000) knlGS:0000000000000000 [ 181.844128] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 181.844134] CR2: ffffffffffffffd6 CR3: 0000000140fbe000 CR4: 00000000003506e0 [ 181.844141] Call Trace: [ 181.844146] <TASK> [ 181.844153] ? show_regs+0x6d/0x80 [ 181.844167] ? __die+0x24/0x80 [ 181.844179] ? page_fault_oops+0x99/0x1b0 [ 181.844192] ? do_user_addr_fault+0x31d/0x6b0 [ 181.844204] ? exc_page_fault+0x83/0x1b0 [ 181.844216] ? asm_exc_page_fault+0x27/0x30 [ 181.844237] dcn20_get_dcc_compression_cap+0x23/0x30 [amdgpu] [ 181.845115] amdgpu_dm_plane_validate_dcc.constprop.0+0xe5/0x180 [amdgpu] [ 181.845985] amdgpu_dm_plane_fill_plane_buffer_attributes+0x300/0x580 [amdgpu] [ 181.846848] fill_dc_plane_info_and_addr+0x258/0x350 [amdgpu] [ 181.847734] fill_dc_plane_attributes+0x162/0x350 [amdgpu] [ 181.848748] dm_update_plane_state.constprop.0+0x4e3/0x6b0 [amdgpu] [ 181.849791] ? dm_update_plane_state.constprop.0+0x4e3/0x6b0 [amdgpu] [ 181.850840] amdgpu_dm_atomic_check+0xdfe/0x1760 [amdgpu] Signed-off-by: Aurabindo Pillai <[email protected]> Reviewed-by: Rodrigo Siqueira <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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Nov 6, 2024
[ Upstream commit eaf3adb ] When programming phantom pipe, since cursor_width is explicity set to 0, this causes calculation logic to trigger overflow for an unsigned int triggering the kernel's UBSAN check as below: [ 40.962845] UBSAN: shift-out-of-bounds in /tmp/amd.EfpumTkO/amd/amdgpu/../display/dc/dml2/dml21/src/dml2_core/dml2_core_dcn4_calcs.c:3312:34 [ 40.962849] shift exponent 4294967170 is too large for 32-bit type 'unsigned int' [ 40.962852] CPU: 1 PID: 1670 Comm: gnome-shell Tainted: G W OE 6.5.0-41-generic #41~22.04.2-Ubuntu [ 40.962854] Hardware name: Gigabyte Technology Co., Ltd. X670E AORUS PRO X/X670E AORUS PRO X, BIOS F21 01/10/2024 [ 40.962856] Call Trace: [ 40.962857] <TASK> [ 40.962860] dump_stack_lvl+0x48/0x70 [ 40.962870] dump_stack+0x10/0x20 [ 40.962872] __ubsan_handle_shift_out_of_bounds+0x1ac/0x360 [ 40.962878] calculate_cursor_req_attributes.cold+0x1b/0x28 [amdgpu] [ 40.963099] dml_core_mode_support+0x6b91/0x16bc0 [amdgpu] [ 40.963327] ? srso_alias_return_thunk+0x5/0x7f [ 40.963331] ? CalculateWatermarksMALLUseAndDRAMSpeedChangeSupport+0x18b8/0x2790 [amdgpu] [ 40.963534] ? srso_alias_return_thunk+0x5/0x7f [ 40.963536] ? dml_core_mode_support+0xb3db/0x16bc0 [amdgpu] [ 40.963730] dml2_core_calcs_mode_support_ex+0x2c/0x90 [amdgpu] [ 40.963906] ? srso_alias_return_thunk+0x5/0x7f [ 40.963909] ? dml2_core_calcs_mode_support_ex+0x2c/0x90 [amdgpu] [ 40.964078] core_dcn4_mode_support+0x72/0xbf0 [amdgpu] [ 40.964247] dml2_top_optimization_perform_optimization_phase+0x1d3/0x2a0 [amdgpu] [ 40.964420] dml2_build_mode_programming+0x23d/0x750 [amdgpu] [ 40.964587] dml21_validate+0x274/0x770 [amdgpu] [ 40.964761] ? srso_alias_return_thunk+0x5/0x7f [ 40.964763] ? resource_append_dpp_pipes_for_plane_composition+0x27c/0x3b0 [amdgpu] [ 40.964942] dml2_validate+0x504/0x750 [amdgpu] [ 40.965117] ? dml21_copy+0x95/0xb0 [amdgpu] [ 40.965291] ? srso_alias_return_thunk+0x5/0x7f [ 40.965295] dcn401_validate_bandwidth+0x4e/0x70 [amdgpu] [ 40.965491] update_planes_and_stream_state+0x38d/0x5c0 [amdgpu] [ 40.965672] update_planes_and_stream_v3+0x52/0x1e0 [amdgpu] [ 40.965845] ? srso_alias_return_thunk+0x5/0x7f [ 40.965849] dc_update_planes_and_stream+0x71/0xb0 [amdgpu] Fix this by adding a guard for checking cursor width before triggering the size calculation. Reviewed-by: Rodrigo Siqueira <[email protected]> Signed-off-by: Aurabindo Pillai <[email protected]> Signed-off-by: Wayne Lin <[email protected]> Tested-by: Daniel Wheeler <[email protected]> Signed-off-by: Alex Deucher <[email protected]> Signed-off-by: Sasha Levin <[email protected]>
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It's a common error to grant too much permission to these objects, with impact ranging from denial of service and information leaking to privilege escalation.
https://labs.portcullis.co.uk/whitepapers/memory-squatting-attacks-on-system-v-shared-memory/
This creates the kernel.harden_ipc sysctl that when enabled will deny access to overly-permissive IPC objects given the following criteria:
Processes with CAP_IPC_OWNER are still permitted to access these IPC objects.
This is based on GRKERNSEC_HARDEN_IPC.