Commit 6e24f5a1 authored by Filipe Manana's avatar Filipe Manana Committed by Greg Kroah-Hartman

Btrfs: setup a nofs context for memory allocation at __btrfs_set_acl

commit a0873490 upstream.

We are holding a transaction handle when setting an acl, therefore we can
not allocate the xattr value buffer using GFP_KERNEL, as we could deadlock
if reclaim is triggered by the allocation, therefore setup a nofs context.

Fixes: 39a27ec1 ("btrfs: use GFP_KERNEL for xattr and acl allocations")
CC: stable@vger.kernel.org # 4.9+
Reviewed-by: default avatarNikolay Borisov <nborisov@suse.com>
Signed-off-by: default avatarFilipe Manana <fdmanana@suse.com>
Reviewed-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 61f92096
No related merge requests found
......@@ -9,6 +9,7 @@
#include <linux/posix_acl_xattr.h>
#include <linux/posix_acl.h>
#include <linux/sched.h>
#include <linux/sched/mm.h>
#include <linux/slab.h>
#include "ctree.h"
......@@ -72,8 +73,16 @@ static int __btrfs_set_acl(struct btrfs_trans_handle *trans,
}
if (acl) {
unsigned int nofs_flag;
size = posix_acl_xattr_size(acl->a_count);
/*
* We're holding a transaction handle, so use a NOFS memory
* allocation context to avoid deadlock if reclaim happens.
*/
nofs_flag = memalloc_nofs_save();
value = kmalloc(size, GFP_KERNEL);
memalloc_nofs_restore(nofs_flag);
if (!value) {
ret = -ENOMEM;
goto out;
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment