From 3d8e72d97411370aab662e85e2c3a7b26555179c Mon Sep 17 00:00:00 2001 From: Jan Harkes Date: Mon, 8 Nov 2021 18:34:33 -0800 Subject: [PATCH] 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 Cc: Alex Shi Cc: Jing Yangyang Cc: Xin Tan Cc: Xiyu Yang Cc: Zeal Robot Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/coda/upcall.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c index eb3b1898da46..59f6cfd06f96 100644 --- a/fs/coda/upcall.c +++ b/fs/coda/upcall.c @@ -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; }