bug#64316: closed (ASAN failures in dir.c)

[GNU bug Tracking System]

Your message dated Tue, 27 Jun 2023 09:40:06 -0700
with message-id <df912544-f16b-cf8b-b85c-92ea1bf50571@cs.ucla.edu>
and subject line Re: [bug-diffutils] bug#64316: ASAN failures in dir.c
has caused the debbugs.gnu.org bug report #64316,
regarding ASAN failures in dir.c
to be marked as done.

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-- 
64316: https://debbugs.gnu.org/cgi/bugreport.cgi?bug=64316
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> --- Begin Message ---
>
>
>
> Subject: 
>
> ASAN failures in dir.c
>
>
>
>
> Date: 
>
> Tue, 27 Jun 2023 15:04:48 +0200
>
>
>
>
> User-agent: 
>
> Mozilla/5.0 (Windows NT 10.0; WOW64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0
>
>
>
>
> Hello list.
>
> Since some time ago, building diff.exe with ASAN (on Windows-10),
> causes it to trigger on illegal use of memcpy().
> For example:
>
> ==3752==ERROR: AddressSanitizer: heap-use-after-free on address 0x121647e20772 
> at
> pc 0x7ffc6e93727e bp 0x00d589efdba0 sp 0x00d589efd330
> WRITE of size 17 at 0x121647e20772 thread T0
>     #0 0x7ffc6e93727d in __asan_memcpy 
> D:\a\_work\1\s\src\vctools\asan\llvm\compiler-rt\li\asan\asan_interceptors_memintrinsics.cpp:22
>     #1 0x7ff604834af1 in dir_read F:\MinGW32\src\gnu\GNU-diff\src\dir.c:101
>     #2 0x7ff604832ec7 in diff_dirs F:\MinGW32\src\gnu\GNU-diff\src\dir.c:214
>     #3 0x7ff60482dc37 in compare_files 
> F:\MinGW32\src\gnu\GNU-diff\src\diff.c:1369
>     #4 0x7ff604833b1b in diff_dirs F:\MinGW32\src\gnu\GNU-diff\src\dir.c:289
>     #5 0x7ff60482dc37 in compare_files 
> F:\MinGW32\src\gnu\GNU-diff\src\diff.c:1369
>     #6 0x7ff60483270e in main F:\MinGW32\src\gnu\GNU-diff\src\diff.c:862
>     ...
>
> -----------------------
>
> This causes Heap Corruption all over the place.
>
> I'm not sure this is an issue with Gnulib or diff. But reverting this
> patch:
>
>
> diff --git a/src/dir.c b/src/dir.c
> index ba9403b..773afeb 100644
> --- a/src/dir.c
> +++ b/src/dir.c
> @@ -95,13 +95,9 @@ dir_read (struct file_data const *dir, struct dirdata 
> *dirdata)
>            if (excluded_file_name (excluded, d_name))
>              continue;
>
> -          while (data_alloc - data_used < d_size)
> -            {
> -              if (IDX_MAX / 2 <= data_alloc)
> -                xalloc_die ();
> -              dirdata->data = data = xirealloc (data, data_alloc *= 2);
> -            }
> -
> +          if (data_alloc - data_used < d_size)
> +           dirdata->data = xpalloc (dirdata->data, &data_alloc,
> +                                    d_size - (data_alloc - data_used), -1, 1);
>            memcpy (data + data_used, d_name, d_size);
>            data_used += d_size;
>            nnames++;
>
> --------
>
> it work with ASAN too (although much slower).
>
> --
> --gv
>
>
>
> --- End Message ---

--- Begin Message --- Subject: Re: [bug-diffutils] bug#64316: ASAN failures in dir.c Date: Tue, 27 Jun 2023 09:40:06 -0700 User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.11.0 Thanks for reporting that bug, which I recently introduced. I installed the attached to fix it.

0001-diff-fix-xpalloc-typo.patch
Description: Text Data

--- End Message ---