A bug report in patch utility.

[Sung Kwan Kang]

To whom it may concern,

Hello, I think I found a bug in GNU patch, specifically in
patch-2.5.4.tar.gz package. When patching a file it kept crashing with
'Segmentation Fault', and I figured out that the following code in line
794 in partime.c was problematic:

    ...
    while (!ISALNUM ((unsigned char) *s))
    ...

Which should read:

    ...
    while (!ISALNUM ((unsigned char) *s) && *s)
    ...

Just like similar other codes in the same file. It was processing the
output of 'diff -c' and encountered timestamp string such as:

    *** foobar.cpp  2003-04-01 16:24:33.000000000 -0800
    --- ../foobar.cpp   2003-04-07 16:34:05.000000000 -0700
    ...

And that piece of code was expecting some alphanumeric token after
"-0800" string, which never occurs. So the pointer went out of bound
without stopping unless there happens to be an alphanumeric character
in that range.

Please review this finding. I attached patch file for my fix.

Thanks,
SungKwan Kang

 <<patch.txt>>

patch.txt
Description: patch.txt