Hi Georges
On Thu, Aug 29, 2024 at 9:55 PM Aureau, Georges (Kernel Tools ERT)
<georges.aureau@xxxxxxx> wrote:
>
> Crash “kmem address” not working properly when redzone is enabled.
>
> When "slub_debug" is enabled with redzoning, "kmem address" does not work properly.
> The "red_left_pad" member within "struct kmem_cache" is currently an "unsigned int",
> it used to be an "int", but it never was a "long", hence "red_left_pad" in do_slab_slub()
> was not initialized properly. This "red_left_pad" issue resulted in reporting free objects
> as "[ALLOCATED]", and in reporting bogus object addresses when using "set redzone off".
>
Thanks for the fix, LGTM, so ack.
Thanks,
Tao Liu
> Signed-off-by: Georges Aureau <georges.aureau@xxxxxxx>
> --
> diff --git a/memory.c b/memory.c
> index a74ebaf..967a9cf 100644
> --- a/memory.c
> +++ b/memory.c
> @@ -19637,7 +19637,8 @@ do_slab_slub(struct meminfo *si, int verbose)
> int i, free_objects, cpu_slab, is_free, node;
> ulong p, q;
> #define SLAB_RED_ZONE 0x00000400UL
> - ulong flags, red_left_pad;
> + ulong flags;
> + uint red_left_pad;
>
> if (!si->slab) {
> if (CRASHDEBUG(1))
> @@ -19727,7 +19728,7 @@ do_slab_slub(struct meminfo *si, int verbose)
> if (VALID_MEMBER(kmem_cache_red_left_pad)) {
> flags = ULONG(si->cache_buf + OFFSET(kmem_cache_flags));
> if (flags & SLAB_RED_ZONE)
> - red_left_pad = ULONG(si->cache_buf + OFFSET(kmem_cache_red_left_pad));
> + red_left_pad = UINT(si->cache_buf + OFFSET(kmem_cache_red_left_pad));
> }
>
> for (p = vaddr; p < vaddr + objects * si->size; p += si->size) {
> --
> Crash-utility mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxxxxxx
> To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxxxxxx
> https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
> Contribution Guidelines: https://github.com/crash-utility/crash/wiki
--
Crash-utility mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxxxxxx
https://${domain_name}/admin/lists/devel.lists.crash-utility.osci.io/
Contribution Guidelines: https://github.com/crash-utility/crash/wiki
