From: Liu Bo <bo.li.liu@xxxxxxxxxx> commit 3d8da67817606380fdadfa483d4dba5c3a5446c6 upstream. The struct 'map_lookup' uses type int for @stripe_len, while btrfs_chunk_stripe_len() can return a u64 value, and it may end up with @stripe_len being undefined value and it can lead to 'divide error' in __btrfs_map_block(). This changes 'map_lookup' to use type u64 for stripe_len, also right now we only use BTRFS_STRIPE_LEN for stripe_len, so this adds a valid checker for BTRFS_STRIPE_LEN. Reported-by: Vegard Nossum <vegard.nossum@xxxxxxxxxx> Reported-by: Quentin Casasnovas <quentin.casasnovas@xxxxxxxxxx> Signed-off-by: Liu Bo <bo.li.liu@xxxxxxxxxx> Reviewed-by: David Sterba <dsterba@xxxxxxxx> [ folded division fix to scrub_raid56_parity ] Signed-off-by: David Sterba <dsterba@xxxxxxxx> --- fs/btrfs/scrub.c | 2 +- fs/btrfs/volumes.c | 2 +- fs/btrfs/volumes.h | 2 +- 3 files changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 92bf5ee732fb..160ac3e23270 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -2858,7 +2858,7 @@ static noinline_for_stack int scrub_raid56_parity(struct scrub_ctx *sctx, int extent_mirror_num; int stop_loop = 0; - nsectors = map->stripe_len / root->sectorsize; + nsectors = div_u64(map->stripe_len, root->sectorsize); bitmap_len = scrub_calc_parity_bitmap_len(nsectors); sparity = kzalloc(sizeof(struct scrub_parity) + 2 * bitmap_len, GFP_NOFS); diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 27a4f2e0856d..f4442fb6b8d4 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -6249,7 +6249,7 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key, "invalid chunk length %llu", length); return -EIO; } - if (!is_power_of_2(stripe_len)) { + if (!is_power_of_2(stripe_len) || stripe_len != BTRFS_STRIPE_LEN) { btrfs_err(root->fs_info, "invalid chunk stripe length: %llu", stripe_len); return -EIO; diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 1939ebde63df..7507be74f7da 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -347,7 +347,7 @@ struct map_lookup { u64 type; int io_align; int io_width; - int stripe_len; + u64 stripe_len; int sector_size; int num_stripes; int sub_stripes; -- 2.7.1 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html