From: Josef Bacik Date: Sat, 20 Apr 2013 03:45:33 +0000 (-0400) Subject: Btrfs: deal with bad mappings in btrfs_map_block X-Git-Tag: v3.10-rc1~31^2~35 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=9bb91873e32af6305a1c5239024674e4a5a97e92;p=karo-tx-linux.git Btrfs: deal with bad mappings in btrfs_map_block Martin Steigerwald reported a BUG_ON() in btrfs_map_block where we didn't find a chunk for a particular block we were trying to map. This happened because the block was bogus. We shouldn't be BUG_ON()'ing in this case, just print a message and return an error. This came from reada_add_block and it appears to deal with an error fine so we should be good there. Thanks, Reported-by: Martin Steigerwald Signed-off-by: Josef Bacik --- diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 76ded9eb77a7..c8a315d4b86f 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -4406,10 +4406,16 @@ static int __btrfs_map_block(struct btrfs_fs_info *fs_info, int rw, btrfs_crit(fs_info, "unable to find logical %llu len %llu", (unsigned long long)logical, (unsigned long long)*length); - BUG(); + return -EINVAL; + } + + if (em->start > logical || em->start + em->len < logical) { + btrfs_crit(fs_info, "found a bad mapping, wanted %Lu, " + "found %Lu-%Lu\n", logical, em->start, + em->start + em->len); + return -EINVAL; } - BUG_ON(em->start > logical || em->start + em->len < logical); map = (struct map_lookup *)em->bdev; offset = logical - em->start;