This is a note to let you know that I've just added the patch titled
btrfs: send: handle unexpected data in header buffer in begin_cmd()
to the 5.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
btrfs-send-handle-unexpected-data-in-header-buffer-i.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 016f007211eea470364dd8593ffd0917453e8fc9
Author: David Sterba <dsterba@xxxxxxxx>
Date: Tue Feb 6 22:47:13 2024 +0100
btrfs: send: handle unexpected data in header buffer in begin_cmd()
[ Upstream commit e80e3f732cf53c64b0d811e1581470d67f6c3228 ]
Change BUG_ON to a proper error handling in the unlikely case of seeing
data when the command is started. This is supposed to be reset when the
command is finished (send_cmd, send_encoded_extent).
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
index 576c027909f8a..e1063ef3dece5 100644
--- a/fs/btrfs/send.c
+++ b/fs/btrfs/send.c
@@ -692,7 +692,12 @@ static int begin_cmd(struct send_ctx *sctx, int cmd)
if (WARN_ON(!sctx->send_buf))
return -EINVAL;
- BUG_ON(sctx->send_size);
+ if (unlikely(sctx->send_size != 0)) {
+ btrfs_err(sctx->send_root->fs_info,
+ "send: command header buffer not empty cmd %d offset %llu",
+ cmd, sctx->send_off);
+ return -EINVAL;
+ }
sctx->send_size += sizeof(*hdr);
hdr = (struct btrfs_cmd_header *)sctx->send_buf;
