Bug#166488: on regexec borkage in libc 2.3.1-3
It seems like it is not really related to efence, just that it is an
intermittant type of bug and seemingly random things can make it crash.
But if you run any regex using prog (ex:
LD_LIBRARY_PATH=/usr/lib/debug:/usr/lib/libstdc++_debug valgrind apt-cache search 'a.*dodebebe'
) through valgrind, you can see many errors even if it does not segfault.
such as:
==1541== Use of uninitialised value of size 4
==1541== at 0x40444A36: re_string_context_at (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x404447C3: re_string_reconstruct (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x4043FAE3: re_search_internal (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x4043F1F2: __regexec (in /usr/lib/debug/libc-2.3.1.so)
==1541==
==1541== Conditional jump or move depends on uninitialised value(s)
==1541== at 0x40444A44: re_string_context_at (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x404447C3: re_string_reconstruct (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x4043FAE3: re_search_internal (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x4043F1F2: __regexec (in /usr/lib/debug/libc-2.3.1.so)
==1541==
==1541== Invalid read of size 1
==1541== at 0x404449E0: re_string_context_at (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x404447C3: re_string_reconstruct (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x4043FAE3: re_search_internal (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x4043F1F2: __regexec (in /usr/lib/debug/libc-2.3.1.so)
==1541== Address 0x40CC45EE is 1 bytes after a block of size 13 alloc'd
==1541== at 0x400456AB: malloc (/home/cyrille/Code/2002/packages/my-packages/valgrind-1.0.4/vg_clientfuncs.c:100)
==1541== by 0x40045C14: realloc (/home/cyrille/Code/2002/packages/my-packages/valgrind-1.0.4/vg_clientfuncs.c:262)
==1541== by 0x40443FAD: re_string_realloc_buffers (in /usr/lib/debug/libc-2.3.1.so)
==1541== by 0x40443DA8: re_string_allocate (in /usr/lib/debug/libc-2.3.1.so)
Downgrading to libc6 2.2.5-14.3 makes the errors go away.
--
Matthew Mueller
donut@azstarnet.com
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