3.16.70-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Dan Robertson <dan@xxxxxxxxxxxxxxx>
commit e49be14b8d80e23bb7c53d78c21717a474ade76b upstream.
The scrub_ctx csum_list member must be initialized before scrub_free_ctx
is called. If the csum_list is not initialized beforehand, the
list_empty call in scrub_free_csums will result in a null deref if the
allocation fails in the for loop.
Fixes: a2de733c78fa ("btrfs: scrub")
Reviewed-by: Nikolay Borisov <nborisov@xxxxxxxx>
Signed-off-by: Dan Robertson <dan@xxxxxxxxxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
fs/btrfs/scrub.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/fs/btrfs/scrub.c
+++ b/fs/btrfs/scrub.c
@@ -417,6 +417,7 @@ struct scrub_ctx *scrub_setup_ctx(struct
sctx->pages_per_rd_bio = pages_per_rd_bio;
sctx->curr = -1;
sctx->dev_root = dev->dev_root;
+ INIT_LIST_HEAD(&sctx->csum_list);
for (i = 0; i < SCRUB_BIOS_PER_SCTX; ++i) {
struct scrub_bio *sbio;
@@ -444,7 +445,6 @@ struct scrub_ctx *scrub_setup_ctx(struct
atomic_set(&sctx->workers_pending, 0);
atomic_set(&sctx->cancel_req, 0);
sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy);
- INIT_LIST_HEAD(&sctx->csum_list);
spin_lock_init(&sctx->list_lock);
spin_lock_init(&sctx->stat_lock);
