On Tue, Oct 13, 2026 at 10:23:43PM -0700, Kees Cook wrote:
> Since commit 734bbc1c97ea7 ("ipc, msg: Use dedicated slab buckets for
> alloc_msg()"), alloc_msg() allocates with GFP_KERNEL, and a msg_msg is
> accounted only through SLAB_ACCOUNT on its bucket caches. With
> CONFIG_SLAB_BUCKETS=n, kmem_buckets_create() creates no caches and
> kmem_buckets_alloc() is a GFP_KERNEL kmalloc() from the general caches,
> which do not account it; the same happens when kmem_buckets_create()
> fails. Either way, the allocation is not charged to the sender's memory
> cgroup.
>
> Allocate with GFP_KERNEL_ACCOUNT again, as before that commit, so the
> allocation is charged whichever cache serves it.
>
> Build tested ARCH=x86_64 defconfig with GCC 16.2.0, with
> CONFIG_SLAB_BUCKETS as y and n.
>
> Fixes: 734bbc1c97ea7 ("ipc, msg: Use dedicated slab buckets for alloc_msg()")
> Cc: [email protected]
> Signed-off-by: Kees Cook <[email protected]>
Looks good to me,
Reviewed-by: Harry Yoo (Meta) <[email protected]>
Thanks!
