netdev - [PATCH] can: ti_hecc: fix close when napi poll is active

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-next>] [day] [month] [year] [list]

Date:   Sat,  7 Apr 2018 22:21:39 +0200
From:   Jeroen Hofstee <jhofstee@...tronenergy.com>
To:     linux-can@...r.kernel.org
Cc:     jhofstee@...tronenergy.com,
        Wolfgang Grandegger <wg@...ndegger.com>,
        Marc Kleine-Budde <mkl@...gutronix.de>, netdev@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: [PATCH] can: ti_hecc: fix close when napi poll is active

When closing this CAN interface while napi poll is active, for example with:
`ip link set can0 down` several interfaces freeze. This seemed to be caused
by napi_disable called from ti_hecc_close expecting the scheduled probe to
either return quota or call napi_complete. Since the poll functions has a
check for netif_running it returns 0 and doesn't call napi_complete and hence
violates the napi its expectation.

So remove this check, so either napi_complete is called or quota is returned.

Signed-off-by: Jeroen Hofstee <jhofstee@...tronenergy.com>
---
 drivers/net/can/ti_hecc.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/drivers/net/can/ti_hecc.c b/drivers/net/can/ti_hecc.c
index db6ea93..42813d3 100644
--- a/drivers/net/can/ti_hecc.c
+++ b/drivers/net/can/ti_hecc.c
@@ -603,9 +603,6 @@ static int ti_hecc_rx_poll(struct napi_struct *napi, int quota)
 	u32 mbx_mask;
 	unsigned long pending_pkts, flags;

-	if (!netif_running(ndev))
-		return 0;
-
 	while ((pending_pkts = hecc_read(priv, HECC_CANRMP)) &&
 		num_pkts < quota) {
 		mbx_mask = BIT(priv->rx_next); /* next rx mailbox to process */
-- 
2.7.4