From a587be2f8750e5c5e67c3dd502d1f8ed34d1269d Mon Sep 17 00:00:00 2001
From: Kees Cook <keescook@chromium.org>
Date: Fri, 5 Nov 2021 13:36:27 -0700
Subject: [PATCH] UPSTREAM: slab: add __alloc_size attributes for better bounds
 checking

As already done in GrapheneOS, add the __alloc_size attribute for
regular kmalloc interfaces, to provide additional hinting for better
bounds checking, assisting CONFIG_FORTIFY_SOURCE and other compiler
optimizations.

Link: https://lkml.kernel.org/r/20210930222704.2631604-5-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Co-developed-by: Daniel Micay <danielmicay@gmail.com>
Signed-off-by: Daniel Micay <danielmicay@gmail.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andy Whitcroft <apw@canonical.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Dwaipayan Ray <dwaipayanray1@gmail.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: Alexandre Bounine <alex.bou9@gmail.com>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Jing Xiangfeng <jingxiangfeng@huawei.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: kernel test robot <lkp@intel.com>
Cc: Matt Porter <mporter@kernel.crashing.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Souptick Joarder <jrdr.linux@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit c37495d6254c237578db3121dcf79857e033f8ff)
[Note: only the kmem_cache_alloc_trace and kmem_cache_alloc_node_trace
 portions of this commit is being applied, in a quest to find the
 offending part of the commit as part of this is breaking cuttlefish
 builds - gregkh]
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Id4fb0d6ad1b24751ddf2e5122fac4b462eca288e
---
 include/linux/slab.h | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/include/linux/slab.h b/include/linux/slab.h
index dd3fc283c36b..fdbc3b8f6132 100644
--- a/include/linux/slab.h
+++ b/include/linux/slab.h
@@ -465,23 +465,23 @@ static __always_inline void *kmem_cache_alloc_node(struct kmem_cache *s, gfp_t f
 
 #ifdef CONFIG_TRACING
 extern void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t flags, size_t size)
-				   __assume_slab_alignment __malloc;
+				   __assume_slab_alignment __alloc_size(3);
 
 #ifdef CONFIG_NUMA
 extern void *kmem_cache_alloc_node_trace(struct kmem_cache *s, gfp_t gfpflags,
-					 int node, size_t size) __assume_slab_alignment __malloc;
+					 int node, size_t size) __assume_slab_alignment
+								__alloc_size(4);
 #else
-static __always_inline void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
-							 gfp_t gfpflags, int node,
-							 size_t size)
+static __always_inline __alloc_size(4) void *kmem_cache_alloc_node_trace(struct kmem_cache *s,
+						 gfp_t gfpflags, int node, size_t size)
 {
 	return kmem_cache_alloc_trace(s, gfpflags, size);
 }
 #endif /* CONFIG_NUMA */
 
 #else /* CONFIG_TRACING */
-static __always_inline void *kmem_cache_alloc_trace(struct kmem_cache *s, gfp_t flags,
-						    size_t size)
+static __always_inline __alloc_size(3) void *kmem_cache_alloc_trace(struct kmem_cache *s,
+								    gfp_t flags, size_t size)
 {
 	void *ret = kmem_cache_alloc(s, flags);