diff options
| author | Daniel Xu <dxu@dxuuu.xyz> | 2020-10-08 18:09:10 -0700 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2020-10-26 15:03:48 +0100 |
| commit | 85d07fbe09efd1c529ff3e025e2f0d2c6c96a1b7 (patch) | |
| tree | 8b61245838e4906ee46098b550e1930eee222b7b /fs | |
| parent | cad69d139651423b9cb8917f514740ed3f08b10a (diff) | |
btrfs: tree-checker: validate number of chunk stripes and parity
If there's no parity and num_stripes < ncopies, a crafted image can
trigger a division by zero in calc_stripe_length().
The image was generated through fuzzing.
CC: stable@vger.kernel.org # 5.4+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=209587
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/tree-checker.c | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/fs/btrfs/tree-checker.c b/fs/btrfs/tree-checker.c index f0ffd5ee77bd..8784b74f5232 100644 --- a/fs/btrfs/tree-checker.c +++ b/fs/btrfs/tree-checker.c @@ -760,18 +760,36 @@ int btrfs_check_chunk_valid(struct extent_buffer *leaf, u64 type; u64 features; bool mixed = false; + int raid_index; + int nparity; + int ncopies; length = btrfs_chunk_length(leaf, chunk); stripe_len = btrfs_chunk_stripe_len(leaf, chunk); num_stripes = btrfs_chunk_num_stripes(leaf, chunk); sub_stripes = btrfs_chunk_sub_stripes(leaf, chunk); type = btrfs_chunk_type(leaf, chunk); + raid_index = btrfs_bg_flags_to_raid_index(type); + ncopies = btrfs_raid_array[raid_index].ncopies; + nparity = btrfs_raid_array[raid_index].nparity; if (!num_stripes) { chunk_err(leaf, chunk, logical, "invalid chunk num_stripes, have %u", num_stripes); return -EUCLEAN; } + if (num_stripes < ncopies) { + chunk_err(leaf, chunk, logical, + "invalid chunk num_stripes < ncopies, have %u < %d", + num_stripes, ncopies); + return -EUCLEAN; + } + if (nparity && num_stripes == nparity) { + chunk_err(leaf, chunk, logical, + "invalid chunk num_stripes == nparity, have %u == %d", + num_stripes, nparity); + return -EUCLEAN; + } if (!IS_ALIGNED(logical, fs_info->sectorsize)) { chunk_err(leaf, chunk, logical, "invalid chunk logical, have %llu should aligned to %u", |