[Devel] [PATCH VZ9 v2 3/3] fs/fuse kio: check whether the fuse request has been killed

[Liu Kui]

When receiving a msg with a kRPC zero-copy buffer, kRPC lookups the
corresponding fuse request to get the actual buffer. However the fuse
request could have been killed and having its buffer released. In
case like this, it is not appropriate to return a fatal error to
userspace, instead we return a positive error value to represent
non-fatal error that pertains to the msg only so that userspace can
adapt accordingly.

Related to #VSTOR-98219

Signed-off-by: Liu Kui <kui.liu at virtuozzo.com>
---
 fs/fuse/kio/pcs/pcs_krpc.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/fuse/kio/pcs/pcs_krpc.c b/fs/fuse/kio/pcs/pcs_krpc.c
index bcb11e40e419..6a487fae308a 100644
--- a/fs/fuse/kio/pcs/pcs_krpc.c
+++ b/fs/fuse/kio/pcs/pcs_krpc.c
@@ -484,8 +484,8 @@ static int pcs_krpc_ioctl_send_msg(struct pcs_krpc *krpc, struct pcs_krpc_ioc_se
 			chunk->type = KRPC_CHUNK_TYPE_ZC;
 			chunk->addr = chunk_bdzc->offset;
 			chunk->req = fuse_dev_find_request(chunk_bdzc->devfd, chunk_bdzc->unique);
-			if (!chunk->req) {
-				res = -ENXIO;
+			if (!chunk->req || chunk->req->args->killed) {
+				res = PCS_ERR_NET;
 				goto err_free_data_chunk;
 			}
 			break;
-- 
2.39.5 (Apple Git-154)