Skip to content

Fix datarace in rd_kafka_broker_fetch_toppars #5266

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
antaljanosbenjamin wants to merge 1 commit into
base: master
Choose a base branch
from
+2 −0
Open

Fix datarace in rd_kafka_broker_fetch_toppars #5266

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions src/rdkafka_fetcher.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1106,6 +1106,7 @@ int rd_kafka_broker_fetch_toppars(rd_kafka_broker_t *rkb, rd_ts_t now) {

if (rd_kafka_buf_ApiVersion(rkbuf) >= 9) {
/* CurrentLeaderEpoch */
rd_kafka_toppar_lock(rktp);
if (rktp->rktp_leader_epoch < 0 &&
rd_kafka_has_reliable_leader_epochs(rkb)) {
/* If current leader epoch is set to -1 and
Comment on lines +1109 to 1112
Copy link

Copilot AI Dec 5, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The lock is released before writing to the buffer at line 1128 (FetchOffset), which may also access rktp fields. Verify that the fetch offset write at line 1128 doesn't require the same lock protection, or if it does, the unlock should be moved after that operation.

Copilot uses AI. Check for mistakes.
Expand All @@ -1121,6 +1122,7 @@ int rd_kafka_broker_fetch_toppars(rd_kafka_broker_t *rkb, rd_ts_t now) {
rd_kafka_buf_write_i32(rkbuf,
rktp->rktp_leader_epoch);
}
rd_kafka_toppar_unlock(rktp);
Comment on lines 1122 to +1125
Copy link

Copilot AI Dec 5, 2025

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The lock is released before writing to the buffer at line 1128 (FetchOffset), which may also access rktp fields. Verify that the fetch offset write at line 1128 doesn't require the same lock protection, or if it does, the unlock should be moved after that operation.

Copilot uses AI. Check for mistakes.
}
/* FetchOffset */
rd_kafka_buf_write_i64(rkbuf,
Expand Down