4.5-stable review patch. If anyone has any objections, please let me know.
------------------ From: Josef Bacik <[email protected]> commit e042d1ec4417981dfe9331e47b76f17929bc2ffe upstream. btrfs_map_block can go horribly wrong in the face of fs corruption, lets agree to not be assholes and panic at any possible chance things are all fucked up. Signed-off-by: Josef Bacik <[email protected]> [ removed type casts ] Signed-off-by: David Sterba <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/btrfs/volumes.c | 18 ++++++++++++++++-- 1 file changed, 16 insertions(+), 2 deletions(-) --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -5289,7 +5289,15 @@ static int __btrfs_map_block(struct btrf stripe_nr = div64_u64(stripe_nr, stripe_len); stripe_offset = stripe_nr * stripe_len; - BUG_ON(offset < stripe_offset); + if (offset < stripe_offset) { + btrfs_crit(fs_info, "stripe math has gone wrong, " + "stripe_offset=%llu, offset=%llu, start=%llu, " + "logical=%llu, stripe_len=%llu", + stripe_offset, offset, em->start, logical, + stripe_len); + free_extent_map(em); + return -EINVAL; + } /* stripe_offset is the offset of this block in its stripe*/ stripe_offset = offset - stripe_offset; @@ -5528,7 +5536,13 @@ static int __btrfs_map_block(struct btrf &stripe_index); mirror_num = stripe_index + 1; } - BUG_ON(stripe_index >= map->num_stripes); + if (stripe_index >= map->num_stripes) { + btrfs_crit(fs_info, "stripe index math went horribly wrong, " + "got stripe_index=%u, num_stripes=%u", + stripe_index, map->num_stripes); + ret = -EINVAL; + goto out; + } num_alloc_stripes = num_stripes; if (dev_replace_is_ongoing) {
