| commit | 7780af1e8edf158f503794dbdb87787999daa086 | |
| author | René Scharfe <l.s.r@web.de> | |
| Sat, 15 Jul 2017 19:11:14 +0000 (15 21:11 +0200) | ||
| committer | Junio C Hamano <gitster@pobox.com> | |
| Mon, 17 Jul 2017 21:54:13 +0000 (17 14:54 -0700) | ||
| tree | 9deaeb85b2986fdc9ba4921414be3f103c92d1c6 | treesnapshot (tar.gz zip) |
| parent | 95d67879735cfecfdd85f89e59d993c5b4de8835 | commitdiff |
bswap: convert to unsigned before shifting in get_be32
The pointer p is dereferenced and we get an unsigned char. Before
shifting it's automatically promoted to int. Left-shifting a signed
32-bit value bigger than 127 by 24 places is undefined. Explicitly
convert to a 32-bit unsigned type to avoid undefined behaviour if
the highest bit is set.
Found with Clang's UBSan.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
The pointer p is dereferenced and we get an unsigned char. Before
shifting it's automatically promoted to int. Left-shifting a signed
32-bit value bigger than 127 by 24 places is undefined. Explicitly
convert to a 32-bit unsigned type to avoid undefined behaviour if
the highest bit is set.
Found with Clang's UBSan.
Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
| compat/bswap.h | diffblobblamehistory |