diff mbox series

[2/5] btrfs: raid56: avoid double freeing for rbio if full_stripe_write() failed

Message ID d36ad8fbdc5d90ff09575ed7669eeb6b8048e013.1665397731.git.wqu@suse.com (mailing list archive)
State New, archived
Headers show
Series btrfs: raid56: part 1, refactor/cleanup | expand

Commit Message

Qu Wenruo Oct. 10, 2022, 10:36 a.m. UTC 
Currently if full_stripe_write() failed to allocate the pages for
parity, it will call __free_raid_bio() first, then return -ENOMEM.

But some caller of full_stripe_write() will also call __free_raid_bio()
again, this would cause double freeing.

And it's not a logically sound either, normally we should either free
the memory at the same level where we allocated it, or let endio to
handle everything.

So this patch will solve the double freeing by make
raid56_parity_write() to handle the error and free the rbio.

Just like what we do in raid56_parity_recover().

Signed-off-by: Qu Wenruo <wqu@suse.com>
---
 fs/btrfs/raid56.c | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)
diff mbox series

Patch

diff --git a/fs/btrfs/raid56.c b/fs/btrfs/raid56.c
index 892005f756cf..82c8e991300e 100644
--- a/fs/btrfs/raid56.c
+++ b/fs/btrfs/raid56.c
@@ -1632,10 +1632,8 @@  static int full_stripe_write(struct btrfs_raid_bio *rbio)
 	int ret;
 
 	ret = alloc_rbio_parity_pages(rbio);
-	if (ret) {
-		__free_raid_bio(rbio);
+	if (ret)
 		return ret;
-	}
 
 	ret = lock_stripe_add(rbio);
 	if (ret == 0)
@@ -1823,8 +1821,10 @@  void raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc)
 	 */
 	if (rbio_is_full(rbio)) {
 		ret = full_stripe_write(rbio);
-		if (ret)
+		if (ret) {
+			__free_raid_bio(rbio);
 			goto fail;
+		}
 		return;
 	}
 
@@ -1838,8 +1838,10 @@  void raid56_parity_write(struct bio *bio, struct btrfs_io_context *bioc)
 		list_add_tail(&rbio->plug_list, &plug->rbio_list);
 	} else {
 		ret = __raid56_parity_write(rbio);
-		if (ret)
+		if (ret) {
+			__free_raid_bio(rbio);
 			goto fail;
+		}
 	}
 
 	return;