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8373474: 2 Unintentional format string defect groups in jabswitch.cpp #28949

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8373474: 2 Unintentional format string defect groups in jabswitch.cpp #28949

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DamonGuy Dec 22, 2025
b4bef29
Update printf
DamonGuy Dec 22, 2025
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DamonGuy Dec 22, 2025
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DamonGuy Dec 23, 2025
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16 changes: 8 additions & 8 deletions src/jdk.accessibility/windows/native/jabswitch/jabswitch.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -226,9 +226,9 @@ int modify(bool enable) {
printf("Couldn't create file: %s\n", path);
perror("Error");
} else {
char str[100] = "assistive_technologies=com.sun.java.accessibility.AccessBridge\n";
strcat_s(str, "screen_magnifier_present=true\n");
fprintf(origFile, str);
fprintf(origFile, "%s",
"assistive_technologies=com.sun.java.accessibility.AccessBridge\n"
"screen_magnifier_present=true\n");
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@prrace prrace Dec 22, 2025 •
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I don't think it is what Alexander meant.
I am not sure doing the above would even resolve the complaint because there's still no format string.

I think he meant it should look like
fprintf(origfile, "%s",
"assistive_technologies=com.sun.java.accessibility.AccessBridge\n"screen_magnifier_present=true\n");
or
fprintf(origfile, "%s",
"assistive_technologies=com.sun.java.accessibility.AccessBridge\n" "screen_magnifier_present=true\n");
if you really want to use the automatic concatenation, but I had to check to be sure it would work so ..

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@DamonGuy DamonGuy Dec 22, 2025

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I see your point. I'll leave it as separated again just in case the string literal is updated with anything that can be misinterpreted as a specifier.

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@azvegint azvegint Dec 22, 2025

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I don't think it is what Alexander meant.

Damon understood me correctly. That's what I meant.
#28949 (comment)

I am not sure doing the above would even resolve the complaint because there's still no format string.

It should.

before:

fprintf(origFile, str); // using `str` variable as format string > parfait complains

after:

  fprintf(origFile,
      "assistive_technologies=com.sun.java.accessibility.AccessBridge\n"
      "screen_magnifier_present=true\n");

Here, we provide a format string(without the format specifiers), not the variable.
It's essentially identical to the code on line 301, printf("Unable to get version info.\n");, parfait didn't complain about that line.

if you really want to use the automatic concatenation, but I had to check to be sure it would work so ..

It is in the standard, so I don't see any reason not to use it:
https://en.cppreference.com/w/cpp/language/string_literal.html#Concatenation

So, in my opinion, the variable str is unnecessary here.

just in case the string literal is updated with anything that can be misinterpreted as a specifier.

I suppose it should be detected during the review process for such a change. Currently, there are no format specifiers being used.

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@prrace prrace Dec 22, 2025

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OK fair enough.

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@aivanov-jdk aivanov-jdk Dec 23, 2025 •
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Why can't we use fputs?

                fputs("assistive_technologies=com.sun.java.accessibility.AccessBridge\n"
                      "screen_magnifier_present=true\n",
                      origFile);

No format strings avoid any possible ambiguity and it's much faster as the string is output verbatim without any additional logic to parse a format string and to process the arguments.

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@aivanov-jdk aivanov-jdk Dec 23, 2025

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I guess the same comment applies here:

A similar pattern is used elsewhere in this file. And I don't want this fix to become a reworking of this code, because that isn't a goal here.

Thus, fprintf is fine.

Similarly, it could be worth cleaning up the code to simplify the logic by not using formatted output where it's not needed.

fclose(origFile);
}
} else {
Expand Down Expand Up @@ -314,11 +314,11 @@ void printVersion() {
pVSInfo->dwProductVersionMS & 0xFFFF,
pVSInfo->dwProductVersionLS >> 16,
pVSInfo->dwProductVersionLS & 0xFFFF );
char outputString[100];
strcpy_s(outputString, "jabswitch ");
strcat_s(outputString, versionString);
strcat_s(outputString, "\njabswitch enables or disables the Java Access Bridge.\n");
printf(outputString);
printf(
"jabswitch %s\n"
"jabswitch enables or disables the Java Access Bridge.\n",
versionString
);
Comment on lines +317 to +321
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@aivanov-jdk aivanov-jdk Dec 23, 2025 •
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If versionString isn't used for anything else, we can remove the versionString variable and the call to sprintf_s and put the arguments to print the version directly into the printf call.

}

int regEnable() {
Expand Down