printf.c: fix off-by-one + underflow errors #13592
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Thanks to @Finder16 for reporting these off-by-one and underflow errors. Signed-off-by: Jeff Squyres <[email protected]>
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Pull request overview
This PR fixes two critical bugs in the opal_vsnprintf function: an off-by-one error that caused out-of-bounds memory access when writing the null terminator, and an underflow issue when the buffer size is zero.
- Fixed off-by-one error in null terminator placement from
str[size]tostr[size - 1] - Added
size > 0check to prevent underflow when calculatingsize - 1with unsignedsize_t
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Port of open-mpi/ompi#13592 Signed-off-by: Ralph Castain <[email protected]>
rhc54
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Dec 24, 2025
Port of open-mpi/ompi#13592 Signed-off-by: Ralph Castain <[email protected]>
rhc54
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Port of open-mpi/ompi#13592 Signed-off-by: Ralph Castain <[email protected]> (cherry picked from commit 78af01e)
rhc54
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Dec 30, 2025
Port of open-mpi/ompi#13592 Signed-off-by: Ralph Castain <[email protected]> (cherry picked from commit 78af01e)
rhc54
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Port of open-mpi/ompi#13592 Signed-off-by: Ralph Castain <[email protected]> (cherry picked from commit 78af01e)
hppritcha
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Thanks to @Finder16 for reporting these off-by-one and underflow errors.