netdev - [PATCH AUTOSEL 5.2 175/249] xsk: Properly terminate assignment in xskq_produce_flush

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20190715134655.4076-175-sashal@kernel.org>
Date:   Mon, 15 Jul 2019 09:45:40 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Nathan Chancellor <natechancellor@...il.com>,
        Nick Desaulniers <ndesaulniers@...gle.com>,
        Jonathan Lemon <jonathan.lemon@...il.com>,
        Björn Töpel <bjorn.topel@...el.com>,
        Song Liu <songliubraving@...com>,
        Daniel Borkmann <daniel@...earbox.net>,
        Sasha Levin <sashal@...nel.org>, netdev@...r.kernel.org,
        bpf@...r.kernel.org, xdp-newbies@...r.kernel.org,
        clang-built-linux@...glegroups.com
Subject: [PATCH AUTOSEL 5.2 175/249] xsk: Properly terminate assignment in xskq_produce_flush_desc

From: Nathan Chancellor <natechancellor@...il.com>

[ Upstream commit f7019b7b0ad14bde732b8953161994edfc384953 ]

Clang warns:

In file included from net/xdp/xsk_queue.c:10:
net/xdp/xsk_queue.h:292:2: warning: expression result unused
[-Wunused-value]
        WRITE_ONCE(q->ring->producer, q->prod_tail);
        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/compiler.h:284:6: note: expanded from macro 'WRITE_ONCE'
        __u.__val;                                      \
        ~~~ ^~~~~
1 warning generated.

The q->prod_tail assignment has a comma at the end, not a semi-colon.
Fix that so clang no longer warns and everything works as expected.

Fixes: c497176cb2e4 ("xsk: add Rx receive functions and poll support")
Link: https://github.com/ClangBuiltLinux/linux/issues/544
Signed-off-by: Nathan Chancellor <natechancellor@...il.com>
Acked-by: Nick Desaulniers <ndesaulniers@...gle.com>
Acked-by: Jonathan Lemon <jonathan.lemon@...il.com>
Acked-by: Björn Töpel <bjorn.topel@...el.com>
Acked-by: Song Liu <songliubraving@...com>
Signed-off-by: Daniel Borkmann <daniel@...earbox.net>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 net/xdp/xsk_queue.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h
index 88b9ae24658d..cba4a640d5e8 100644
--- a/net/xdp/xsk_queue.h
+++ b/net/xdp/xsk_queue.h
@@ -288,7 +288,7 @@ static inline void xskq_produce_flush_desc(struct xsk_queue *q)
 	/* Order producer and data */
 	smp_wmb(); /* B, matches C */
 
-	q->prod_tail = q->prod_head,
+	q->prod_tail = q->prod_head;
 	WRITE_ONCE(q->ring->producer, q->prod_tail);
 }
 
-- 
2.20.1