From: Alexander Potapenko <glider@google.com>
Date: Sat, 3 Aug 2019 04:49:22 +0000 (-0700)
Subject: lib/test_meminit.c: use GFP_ATOMIC in RCU critical section
X-Git-Tag: Ubuntu-5.4-5.4.0-11.14~2308^2~2
X-Git-Url: https://git.proxmox.com/?a=commitdiff_plain;h=733d1d1a7745113e2b6a1761300e7e26b6eb6009;p=mirror_ubuntu-focal-kernel.git

lib/test_meminit.c: use GFP_ATOMIC in RCU critical section

kmalloc() shouldn't sleep while in RCU critical section, therefore use
GFP_ATOMIC instead of GFP_KERNEL.

The bug was spotted by the 0day kernel testing robot.

Link: http://lkml.kernel.org/r/20190725121703.210874-1-glider@google.com
Fixes: 7e659650cbda ("lib: introduce test_meminit module")
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reported-by: kernel test robot <lkp@intel.com>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/lib/test_meminit.c b/lib/test_meminit.c
index 62d19f270cad..9729f271d150 100644
--- a/lib/test_meminit.c
+++ b/lib/test_meminit.c
@@ -222,7 +222,7 @@ static int __init do_kmem_cache_size(size_t size, bool want_ctor,
 		 * Copy the buffer to check that it's not wiped on
 		 * free().
 		 */
-		buf_copy = kmalloc(size, GFP_KERNEL);
+		buf_copy = kmalloc(size, GFP_ATOMIC);
 		if (buf_copy)
 			memcpy(buf_copy, buf, size);