fs: fix out-of-bounds write in mkdtemp for long prefixes#64770
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frandle331-yh wants to merge 1 commit into
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fs: fix out-of-bounds write in mkdtemp for long prefixes#64770frandle331-yh wants to merge 1 commit into
frandle331-yh wants to merge 1 commit into
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Mkdtemp() allocated the template buffer as `length + strlen("XXXXXX")`,
leaving no room for the terminating NUL byte that snprintf() writes. For
a single-byte prefix long enough to force the heap allocation path
(length + 6 > the stack-buffer threshold), snprintf() wrote the six 'X'
characters plus its NUL one byte past the end of the buffer -- a 1-byte
heap-buffer-overflow flagged by AddressSanitizer.
Allocate one extra byte for the NUL terminator, matching the `+ 1`
already used by the sibling allocations in the same file.
Signed-off-by: frandle331-yh <s1240100@gmail.com>
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Mkdtemp() allocated the template buffer as
length + strlen("XXXXXX"),leaving no room for the terminating NUL byte that snprintf() writes. For
a single-byte prefix long enough to force the heap allocation path
(length + 6 > the stack-buffer threshold), snprintf() wrote the six 'X'
characters plus its NUL one byte past the end of the buffer -- a 1-byte
heap-buffer-overflow flagged by AddressSanitizer.
Allocate one extra byte for the NUL terminator, matching the
+ 1already used by the sibling allocations in the same file.
Signed-off-by: frandle331-yh s1240100@gmail.com