From 9f30c768c00fd0f0a2ab37ef29d8c8c5a7abdf2e Mon Sep 17 00:00:00 2001 From: Jarek Poplawski <jarkao2@gmail.com> Date: Wed, 13 Feb 2008 11:17:58 +0000 Subject: [PATCH] mkiss: ax_bump() locking fix According to one of OOPSes reported by Jann softirq can break while skb is prepared for netif_rx. The report isn't complete, so the real reason of the later bug could be different, but IMHO this locking break in ax_bump is unsafe and unnecessary. Reported-and-tested-by: Jann Traschewski <jann@gmx.de> Signed-off-by: Jarek Poplawski <jarkao2@gmail.com> Signed-off-by: Jeff Garzik <jeff@garzik.org> --- drivers/net/hamradio/mkiss.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/net/hamradio/mkiss.c b/drivers/net/hamradio/mkiss.c index cfcd15af501e7..30c9b3b0d1319 100644 --- a/drivers/net/hamradio/mkiss.c +++ b/drivers/net/hamradio/mkiss.c @@ -289,7 +289,6 @@ static void ax_bump(struct mkiss *ax) *ax->rbuff &= ~0x20; } } - spin_unlock_bh(&ax->buflock); count = ax->rcount; @@ -297,17 +296,17 @@ static void ax_bump(struct mkiss *ax) printk(KERN_ERR "mkiss: %s: memory squeeze, dropping packet.\n", ax->dev->name); ax->stats.rx_dropped++; + spin_unlock_bh(&ax->buflock); return; } - spin_lock_bh(&ax->buflock); memcpy(skb_put(skb,count), ax->rbuff, count); - spin_unlock_bh(&ax->buflock); skb->protocol = ax25_type_trans(skb, ax->dev); netif_rx(skb); ax->dev->last_rx = jiffies; ax->stats.rx_packets++; ax->stats.rx_bytes += count; + spin_unlock_bh(&ax->buflock); } static void kiss_unesc(struct mkiss *ax, unsigned char s) -- GitLab