Re: [PATCH 4/4] virtiofsd: do_read missing NULL check

[Philippe Mathieu-Daudé]

On 2/4/20 12:05 PM, Dr. David Alan Gilbert (git) wrote:

From: "Dr. David Alan Gilbert" <dgilb...@redhat.com>

Missing a NULL check if the argument fetch fails.

Surprisingly all other calls to fuse_mbuf_iter_advance() do the check.

Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com>

Fixes: Coverity CID 1413119
Signed-off-by: Dr. David Alan Gilbert <dgilb...@redhat.com>
---
  tools/virtiofsd/fuse_lowlevel.c | 4 ++++
  1 file changed, 4 insertions(+)

diff --git a/tools/virtiofsd/fuse_lowlevel.c b/tools/virtiofsd/fuse_lowlevel.c
index 01c418aade..704c0369b2 100644
--- a/tools/virtiofsd/fuse_lowlevel.c
+++ b/tools/virtiofsd/fuse_lowlevel.c
@@ -1116,6 +1116,10 @@ static void do_read(fuse_req_t req, fuse_ino_t nodeid,
          struct fuse_file_info fi;

arg = fuse_mbuf_iter_advance(iter, sizeof(*arg));

+        if (!arg) {
+            fuse_reply_err(req, EINVAL);
+            return;
+        }

memset(&fi, 0, sizeof(fi));

          fi.fh = arg->fh;