diff options
| author | Filipe Manana <fdmanana@suse.com> | 2018-12-13 21:16:56 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-03-23 20:11:22 +0100 |
| commit | 9d7b327affb831572acecd6132cb39d90ace1d6a (patch) | |
| tree | 0d6b279b6d79ed8c3ac6ca8bb49926c217b9854e | |
| parent | 80dcd07c27dfe24f79a40897d8ecac4c38b1875d (diff) | |
Btrfs: setup a nofs context for memory allocation at __btrfs_set_acl
commit a0873490660246db587849a9e172f2b7b21fa88a 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: 39a27ec1004e8 ("btrfs: use GFP_KERNEL for xattr and acl allocations")
CC: stable@vger.kernel.org # 4.9+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/btrfs/acl.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/fs/btrfs/acl.c b/fs/btrfs/acl.c index 3b66c957ea6f..5810463dc6d2 100644 --- a/fs/btrfs/acl.c +++ b/fs/btrfs/acl.c @@ -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; |