From e0188829cb724e7d12a2d4e343b368ff1d6e1471 Mon Sep 17 00:00:00 2001 From: Stanislav Brabec Date: Tue, 8 Dec 2009 21:00:22 -0800 Subject: [PATCH] b44 WOL setup: one-bit-off stack corruption kernel panic fix About 50% of shutdowns of b44 Ethernet adapter ends by kernel panic with kernels compiled with stack-protector. Checking b44_magic_pattern() return values, one call of b44_magic_pattern() returns 127. It means, that set_bit(128, pmask) was called on line 1509. It means that bit 0 of 17th byte of pmask was overwritten. But pmask has only 16 bytes. Stack corruption happens. It seems that set_bit() on line 1509 always writes one bit off. The fix does not only solve the stack corruption, but also makes Wake On LAN working on my onboard B44 on Asus A7V-333X mainboard. It seems that this problem affects all kernel versions since commit 725ad800 ([PATCH] b44: add wol for old nic) on 2006-06-20. Signed-off-by: Stanislav Brabec Signed-off-by: David S. Miller --- drivers/net/b44.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/net/b44.c b/drivers/net/b44.c index 2a9132343b66..4869adb69586 100644 --- a/drivers/net/b44.c +++ b/drivers/net/b44.c @@ -1505,8 +1505,7 @@ static int b44_magic_pattern(u8 *macaddr, u8 *ppattern, u8 *pmask, int offset) for (k = 0; k< ethaddr_bytes; k++) { ppattern[offset + magicsync + (j * ETH_ALEN) + k] = macaddr[k]; - len++; - set_bit(len, (unsigned long *) pmask); + set_bit(len++, (unsigned long *) pmask); } } return len - 1; -- 2.20.1