net: stmmac: dwmac1000: fix out-of-bounds mac address reg setting

Commit Message

Jisheng Zhang April 3, 2020, 2:23 a.m. UTC

From: Jisheng Zhang <[e-mail]>

Commit 9463c4455900 ("net: stmmac: dwmac1000: Clear unused address
entries") cleared the unused mac address entries, but introduced an
out-of bounds mac address register programming bug -- After setting
the secondary unicast mac addresses, the "reg" value has reached
netdev_uc_count() + 1, thus we should only clear address entries
if (addr < perfect_addr_number)

Fixes: 9463c4455900 ("net: stmmac: dwmac1000: Clear unused address entries")
Signed-off-by: Jisheng Zhang <[e-mail]>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

David Miller April 3, 2020, 10:59 p.m. UTC | #1

From: Jisheng Zhang <[e-mail]>
Date: Fri, 3 Apr 2020 10:23:29 +0800

> From: Jisheng Zhang <[e-mail]>
> 
> Commit 9463c4455900 ("net: stmmac: dwmac1000: Clear unused address
> entries") cleared the unused mac address entries, but introduced an
> out-of bounds mac address register programming bug -- After setting
> the secondary unicast mac addresses, the "reg" value has reached
> netdev_uc_count() + 1, thus we should only clear address entries
> if (addr < perfect_addr_number)
> 
> Fixes: 9463c4455900 ("net: stmmac: dwmac1000: Clear unused address entries")
> Signed-off-by: Jisheng Zhang <[e-mail]>

Applied and queued up for -stable, thanks.

Patch

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
index 542784300620..efc6ec1b8027 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac1000_core.c
@@ -207,7 +207,7 @@  static void dwmac1000_set_filter(struct mac_device_info *hw,
 			reg++;
 		}
 
-		while (reg <= perfect_addr_number) {
+		while (reg < perfect_addr_number) {
 			writel(0, ioaddr + GMAC_ADDR_HIGH(reg));
 			writel(0, ioaddr + GMAC_ADDR_LOW(reg));
 			reg++;