coda: check for async upcall request using local state

Originally flagged by Smatch because the code implicitly assumed outSize
is not NULL for non-async upcalls because of a flag that was (not) set in
req->uc_flags.

However req->uc_flags field is in shared state and although the current
code will not allow it to be changed before the async request check the
code is more robust when it tests against the local outSize variable.

Link: https://lkml.kernel.org/r/20210908140308.18491-3-jaharkes@cs.cmu.edu
Signed-off-by: Jan Harkes <jaharkes@cs.cmu.edu>
Cc: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Jing Yangyang <jing.yangyang@zte.com.cn>
Cc: Xin Tan <tanxin.ctf@gmail.com>
Cc: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Cc: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jan Harkes 2021-11-08 18:34:33 -08:00 committed by Linus Torvalds
parent 18319cb478
commit 3d8e72d974

View File

@ -744,7 +744,8 @@ static int coda_upcall(struct venus_comm *vcp,
list_add_tail(&req->uc_chain, &vcp->vc_pending);
wake_up_interruptible(&vcp->vc_waitq);
if (req->uc_flags & CODA_REQ_ASYNC) {
/* We can return early on asynchronous requests */
if (outSize == NULL) {
mutex_unlock(&vcp->vc_mutex);
return 0;
}