| commit | e5672763c44f16ddbc42809f5def7c6a962602bd | |
| author | H.J. Lu <hjl.tools@gmail.com> | |
| Fri, 2 Dec 2022 00:36:02 +0000 (1 16:36 -0800) | ||
| committer | H.J. Lu <hjl.tools@gmail.com> | |
| Fri, 2 Dec 2022 16:18:41 +0000 (2 08:18 -0800) | ||
| tree | a34a3791fc27a9402cb0f78c611e8d5de568c316 | treesnapshot (tar.gz zip) |
| parent | f566b028524149ddfebe7f9770a3befb13b81a13 | commitdiff |
x86-64 strncpy: Properly handle the length parameter [BZ# 29839]
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes strncpy for x32. Tested on x86-64 and x32. On x86-64,
libc.so is the same with and without the fix.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
On x32, the size_t parameter may be passed in the lower 32 bits of a
64-bit register with the non-zero upper 32 bits. The string/memory
functions written in assembly can only use the lower 32 bits of a
64-bit register as length or must clear the upper 32 bits before using
the full 64-bit register for length.
This pach fixes strncpy for x32. Tested on x86-64 and x32. On x86-64,
libc.so is the same with and without the fix.
Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
| sysdeps/x86_64/multiarch/strncpy-avx2.S | diffblobblamehistory | |
| sysdeps/x86_64/multiarch/strncpy-evex.S | diffblobblamehistory |