Bug#901353: wmifs segfaults occasionally

[Doug Torrance]

Control: tags -1 fixed-upstream

On 06/11/2018 03:42 PM, anomie at users.sourceforge.net wrote:
> Package: wmifs
> Version: 1.8-1
> 
> I noticed that wmifs was randomly crashing on my laptop. I have no idea
> how to reproduce it besides letting it run for a long time, it didn't
> seem to be associated with hibernation or anything else obvious. If I
> have multiple instances running, usually only one will crash while the
> others continue without issue.
> 
> Running it under gdb with wmifs-dbgsym installed produced this trace:
> 
>    Program received signal SIGSEGV, Segmentation fault.
>    _IO_fgets (buf=0x7fffffffd9d0 "\001", n=512, fp=0x0) at iofgets.c:47
>    47	iofgets.c: No such file or directory.
>    (gdb) bt
>    #0  _IO_fgets (buf=0x7fffffffd9d0 "\001", n=512, fp=0x0) at iofgets.c:47
>    #1  0x0000555555556d1f in fgets (__stream=0x0, __n=512, __s=0x7fffffffd9d0 "\001") at /usr/include/x86_64-linux-gnu/bits/stdio2.h:263
>    #2  get_statistics (devname=<optimized out>, ip=0x7fffffffdc70, op=0x7fffffffdc78, is=0x7fffffffdc80, os=0x7fffffffdc88) at wmifs.c:767
>    #3  0x00005555555573b9 in wmifs_routine (argc=<optimized out>, argv=<optimized out>) at wmifs.c:555
>    #4  0x0000555555555dbe in main (argc=5, argv=0x7fffffffe198) at wmifs.c:367
> 
> Apparently the fopen() on wmifs.c line 766 can fail in some cases, and
> that needs to be checked for to avoid passing a NULL file pointer to
> fgets(). It could be as simple as inserting
> 
>      if (!fp) {
>          return -1;
>      }
> 
> to match the minimal error handling on subsequent lines when an fgets() fails.

Thanks for your report!

I've just released a new upstream version (1.9) with your patch [1].  It 
should get fixed in Debian soon.

[1] https://www.dockapps.net/wmifs