Re: [PATCH] tools/nolibc/stdlib: fix memory error in realloc()

From: Willy Tarreau
Date: Wed Jan 10 2024 - 01:19:26 EST


Hi,

On Wed, Jan 10, 2024 at 11:11:37AM +0700, Ammar Faizi wrote:
> On Tue, Jan 09, 2024 at 06:44:02PM -0500, Brennan Xavier McManus wrote:
> > Pass user_p_len to memcpy() instead of heap->len to prevent realloc()
> > from copying an extra sizeof(heap) bytes from beyond the allocated
> > region.
> >
> > Signed-off-by: Brennan Xavier McManus <bxmcmanus@xxxxxxxxx>
> > ---
> >
> > All tests from Ammar's original test program pass:
> > https://gist.github.com/ammarfaizi2/db0af6aa0b95a0c7478bce64e349f021
> > This fix was tested with the following added test for realloc():
> > https://github.com/brennan913/nolibc-test/blob/main/nolibc_test.c#L73-L120
>
> Hello Brennan,
>
> Thank you for the fix!
>
> Cc: stable@xxxxxxxxxxxxxxx
> Reviewed-by: Ammar Faizi <ammarfaizi2@xxxxxxxxxxx>
> Fixes: 0e0ff638400be8f497a35b51a4751fd823f6bd6a ("tools/nolibc/stdlib: Implement `malloc()`, `calloc()`, `realloc()` and `free()`")

Thanks both for the fix and the review! I've pushed it to the "fixes"
branch. Thomas, for now I updated the branch to match "next" (which just
got merged) so as to preserve patch ordering, we'll just rebase it once
6.8-rc1 is out.

Willy