5.0-stable review patch. If anyone has any objections, please let me know.
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From: Dan Carpenter dan.carpenter@oracle.com
commit 669e859b5ea7c6f4fce0149d3907c64e550c294b upstream.
We should drop the lock on this error path. This has been found by a static tool.
The lock needs to be released, it's there to protect access to the dev_replace members and is not supposed to be left locked. The value of state that's being switched would need to be artifically changed to an invalid value so the default: branch is taken.
Fixes: d189dd70e255 ("btrfs: fix use-after-free due to race between replace start and cancel") CC: stable@vger.kernel.org # 5.0+ Reviewed-by: Anand Jain anand.jain@oracle.com Signed-off-by: Dan Carpenter dan.carpenter@oracle.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
--- fs/btrfs/dev-replace.c | 1 + 1 file changed, 1 insertion(+)
--- a/fs/btrfs/dev-replace.c +++ b/fs/btrfs/dev-replace.c @@ -862,6 +862,7 @@ int btrfs_dev_replace_cancel(struct btrf btrfs_destroy_dev_replace_tgtdev(tgt_device); break; default: + up_write(&dev_replace->rwsem); result = -EINVAL; }