Bug#481543: libc6: low-memory snprintf provokes internal segfault

[Aurelien Jarno <aurelien@aurel32.net>]

tag 481543 + unreproducible
tag 481543 + moreinfo
thanks

On Fri, May 16, 2008 at 10:30:34PM +0200, Jim Meyering wrote:
> Package: libc6
> Version: 2.7-11
> Severity: normal
> 
> glibc's snprintf function malfunctions (segfault)
> when its internal memory allocation fails.
> FYI, this bug is new in libc6 2.7-11.  I noticed because it provokes
> a new failure in coreutils' printf-surprise test.  This is not a
> problem when using rawhide's glibc-2.8.
> 
>
> $ cat snprintf-test-debbug.c
> #include <stdio.h>
> #include <string.h>
> int
> main(int argc, char **argv)
> {
>   char buf[200];
>   char *fmt = argv[1];
>   if (argc < 2)
>     return 1;
>   return snprintf (buf, sizeof buf, fmt, 1);
> }
> $ gcc snprintf-test-debbug.c
> $ zsh -c 'ulimit -v 5000; ./a.out %$[5*2**20]d'
> zsh: segmentation fault  zsh -c 'ulimit -v 5000; ./a.out %$[5*2**20]d'
> [Exit 139 (SEGV)]

I am unable to reproduce this problem. Moreover version 2.7-11 doesn't
introduce any change in this area.

Please check that the bug is still reproducible on your system and that
downgrading to 2.7-10 actually fixes the problem.

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