[ Upstream commit 1b3922a8bc74231f9a767d1be6d9a061a4d4eeab ]
[BUG] Linux v5.0-rc1 will fail fstests/btrfs/163 with the following kernel message:
BTRFS error (device dm-6): dev extent devid 1 physical offset 13631488 len 8388608 is beyond device boundary 0 BTRFS error (device dm-6): failed to verify dev extents against chunks: -117 BTRFS error (device dm-6): open_ctree failed
[CAUSE] Commit cf90d884b347 ("btrfs: Introduce mount time chunk <-> dev extent mapping check") introduced strict check on dev extents.
We use btrfs_find_device() with dev uuid and fs uuid set to NULL, and only dependent on @devid to find the real device.
For seed devices, we call clone_fs_devices() in open_seed_devices() to allow us search seed devices directly.
However clone_fs_devices() just populates devices with devid and dev uuid, without populating other essential members, like disk_total_bytes.
This makes any device returned by btrfs_find_device(fs_info, devid, NULL, NULL) is just a dummy, with 0 disk_total_bytes, and any dev extents on the seed device will not pass the device boundary check.
[FIX] This patch will try to verify the device returned by btrfs_find_device() and if it's a dummy then re-search in seed devices.
Fixes: cf90d884b347 ("btrfs: Introduce mount time chunk <-> dev extent mapping check") CC: stable@vger.kernel.org # 4.19+ Reported-by: Filipe Manana fdmanana@suse.com Signed-off-by: Qu Wenruo wqu@suse.com Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/btrfs/volumes.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index c20708bfae561..a8297e7489d98 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -7469,6 +7469,18 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info, ret = -EUCLEAN; goto out; } + + /* It's possible this device is a dummy for seed device */ + if (dev->disk_total_bytes == 0) { + dev = find_device(fs_info->fs_devices->seed, devid, NULL); + if (!dev) { + btrfs_err(fs_info, "failed to find seed devid %llu", + devid); + ret = -EUCLEAN; + goto out; + } + } + if (physical_offset + physical_len > dev->disk_total_bytes) { btrfs_err(fs_info, "dev extent devid %llu physical offset %llu len %llu is beyond device boundary %llu",