Old csum type check is wrong and can't catch csum_type 1(not supported). Fix it to avoid hostile 0 division.
Reported-by: Lukas Lueg <lukas.l...@gmail.com> Signed-off-by: Qu Wenruo <quwen...@cn.fujitsu.com> --- Changelog: v2: Fix existing codes other than adding new one. --- fs/btrfs/ctree.h | 1 + fs/btrfs/disk-io.c | 4 ++-- 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index f9c89ca..d6f3aa0 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -173,6 +173,7 @@ struct btrfs_ordered_sum; /* csum types */ #define BTRFS_CSUM_TYPE_CRC32 0 +#define BTRFS_CSUM_LAST_TYPE 0 static int btrfs_csum_sizes[] = { 4, 0 }; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 639f266..e33a01b 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -426,9 +426,9 @@ static int btrfs_check_super_csum(char *raw_disk_sb) } } - if (csum_type >= ARRAY_SIZE(btrfs_csum_sizes)) { + if (csum_type > BTRFS_CSUM_LAST_TYPE) { printk(KERN_ERR "BTRFS: unsupported checksum algorithm %u\n", - csum_type); + csum_type); ret = 1; } -- 2.3.5 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html