From: Petr Štetiar Date: Mon, 16 Mar 2020 08:43:00 +0000 (+0100) Subject: ipq40xx: 5.4: fix of_get_mac_address obsolete usage OOPs X-Git-Tag: v21.02.0-rc1~3441 X-Git-Url: http://git.openwrt.org/?a=commitdiff_plain;h=f521ef5ff3110018fb8b4e6827e2a5d7f32c41f0;p=openwrt%2Fopenwrt.git ipq40xx: 5.4: fix of_get_mac_address obsolete usage OOPs of_get_mac_address returns valid pointer or ERR_PTR since 5.2 via commit d01f449c008a ("of_net: add NVMEM support to of_get_mac_address") so the patch fixes following OOPs on nbg6617: Unable to handle kernel paging request at virtual address ffffffed CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.4.24 #0 PC is at edma_axi_probe+0x444/0x1114 LR is at bus_find_device+0x88/0x9c Where the PC can be resolved to: >>> l *edma_axi_probe+0x444 0xc067be5c is in edma_axi_probe (./include/linux/string.h:378). >>> l *edma_axi_probe+0x43f 0xc067be57 is in edma_axi_probe (drivers/net/ethernet/qualcomm/essedma/edma_axi.c:936) Which leads to the following code fragment: 935 mac_addr = of_get_mac_address(pnp); 936 if (mac_addr) 937 memcpy(edma_netdev[idx_mac]->dev_addr, mac_addr, ETH_ALEN); Where using mac_addr=0xffffffed (-ENODEV) as source address in memcpy() is causing the OOPs. Acked-by: John Crispin Signed-off-by: Petr Štetiar --- diff --git a/target/linux/ipq40xx/files-5.4/drivers/net/ethernet/qualcomm/essedma/edma_axi.c b/target/linux/ipq40xx/files-5.4/drivers/net/ethernet/qualcomm/essedma/edma_axi.c index db5eac2f03..b619bbbab9 100644 --- a/target/linux/ipq40xx/files-5.4/drivers/net/ethernet/qualcomm/essedma/edma_axi.c +++ b/target/linux/ipq40xx/files-5.4/drivers/net/ethernet/qualcomm/essedma/edma_axi.c @@ -933,7 +933,7 @@ static int edma_axi_probe(struct platform_device *pdev) } mac_addr = of_get_mac_address(pnp); - if (mac_addr) + if (!IS_ERR(mac_addr)) memcpy(edma_netdev[idx_mac]->dev_addr, mac_addr, ETH_ALEN); idx_mac++;