Commit 063d006f authored Jan 31, 2013 by Eric Sandeen Committed by Josef Bacik Feb 20, 2013

btrfs: ensure we don't overrun devices_info[] in __btrfs_alloc_chunk



WARN_ON isn't enough, we need to stop the loop if for any reason
we would overrun the devices_info array.

I tried to track down the connection between the length of
the alloc_devices list and the rw_devices counter but
it wasn't immediately obvious, so be defensive about it.

Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>

parent 1971e917

fs/btrfs/volumes.c

+5 −1

Original line number	Diff line number	Diff line
		@@ -3734,12 +3734,16 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
		if (max_avail < BTRFS_STRIPE_LEN * dev_stripes)
		continue;

		if (ndevs == fs_devices->rw_devices) {
		WARN(1, "%s: found more than %llu devices\n",
		__func__, fs_devices->rw_devices);
		break;
		}
		devices_info[ndevs].dev_offset = dev_offset;
		devices_info[ndevs].max_avail = max_avail;
		devices_info[ndevs].total_avail = total_avail;
		devices_info[ndevs].dev = device;
		++ndevs;
		WARN_ON(ndevs > fs_devices->rw_devices);
		}

		/*