[PATCH 1/2] net: stmmac: fix dma queue left shift overflow issue

From: Junxiao Chang <junxiao.chang@intel.com>
To: peppe.cavallaro@st.com, alexandre.torgue@foss.st.com,
	joabreu@synopsys.com, netdev@vger.kernel.org
Cc: junxiao.chang@intel.com
Subject: [PATCH 1/2] net: stmmac: fix dma queue left shift overflow issue
Date: Wed, 13 Jul 2022 16:47:27 +0800	[thread overview]
Message-ID: <20220713084728.1311465-1-junxiao.chang@intel.com> (raw)

When queue number is > 4, left shift overflows due to 32 bits
integer variable. Mask calculation is wrong for MTL_RXQ_DMA_MAP1.

If CONFIG_UBSAN is enabled, kernel dumps below warning:
[   10.363842] ==================================================================
[   10.363882] UBSAN: shift-out-of-bounds in /build/linux-intel-iotg-5.15-8e6Tf4/
linux-intel-iotg-5.15-5.15.0/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c:224:12
[   10.363929] shift exponent 40 is too large for 32-bit type 'unsigned int'
[   10.363953] CPU: 1 PID: 599 Comm: NetworkManager Not tainted 5.15.0-1003-intel-iotg
[   10.363956] Hardware name: ADLINK Technology Inc. LEC-EL/LEC-EL, BIOS 0.15.11 12/22/2021
[   10.363958] Call Trace:
[   10.363960]  <TASK>
[   10.363963]  dump_stack_lvl+0x4a/0x5f
[   10.363971]  dump_stack+0x10/0x12
[   10.363974]  ubsan_epilogue+0x9/0x45
[   10.363976]  __ubsan_handle_shift_out_of_bounds.cold+0x61/0x10e
[   10.363979]  ? wake_up_klogd+0x4a/0x50
[   10.363983]  ? vprintk_emit+0x8f/0x240
[   10.363986]  dwmac4_map_mtl_dma.cold+0x42/0x91 [stmmac]
[   10.364001]  stmmac_mtl_configuration+0x1ce/0x7a0 [stmmac]
[   10.364009]  ? dwmac410_dma_init_channel+0x70/0x70 [stmmac]
[   10.364020]  stmmac_hw_setup.cold+0xf/0xb14 [stmmac]
[   10.364030]  ? page_pool_alloc_pages+0x4d/0x70
[   10.364034]  ? stmmac_clear_tx_descriptors+0x6e/0xe0 [stmmac]
[   10.364042]  stmmac_open+0x39e/0x920 [stmmac]
[   10.364050]  __dev_open+0xf0/0x1a0
[   10.364054]  __dev_change_flags+0x188/0x1f0
[   10.364057]  dev_change_flags+0x26/0x60
[   10.364059]  do_setlink+0x908/0xc40
[   10.364062]  ? do_setlink+0xb10/0xc40
[   10.364064]  ? __nla_validate_parse+0x4c/0x1a0
[   10.364068]  __rtnl_newlink+0x597/0xa10
[   10.364072]  ? __nla_reserve+0x41/0x50
[   10.364074]  ? __kmalloc_node_track_caller+0x1d0/0x4d0
[   10.364079]  ? pskb_expand_head+0x75/0x310
[   10.364082]  ? nla_reserve_64bit+0x21/0x40
[   10.364086]  ? skb_free_head+0x65/0x80
[   10.364089]  ? security_sock_rcv_skb+0x2c/0x50
[   10.364094]  ? __cond_resched+0x19/0x30
[   10.364097]  ? kmem_cache_alloc_trace+0x15a/0x420
[   10.364100]  rtnl_newlink+0x49/0x70

This change fixes MTL_RXQ_DMA_MAP1 mask issue and channel/queue
mapping warning.

Fixes: d43042f4da3e ("net: stmmac: mapping mtl rx to dma channel")
Signed-off-by: Junxiao Chang <junxiao.chang@intel.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
index 96e5d39bb2600..c4d1072fbea39 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_core.c
@@ -269,6 +269,9 @@ static void dwmac4_map_mtl_dma(struct mac_device_info *hw, u32 queue, u32 chan)
 	if (queue == 0 || queue == 4) {
 		value &= ~MTL_RXQ_DMA_Q04MDMACH_MASK;
 		value |= MTL_RXQ_DMA_Q04MDMACH(chan);
+	} else if (queue > 4) {
+		value &= ~MTL_RXQ_DMA_QXMDMACH_MASK(queue - 4);
+		value |= MTL_RXQ_DMA_QXMDMACH(chan, queue - 4);
 	} else {
 		value &= ~MTL_RXQ_DMA_QXMDMACH_MASK(queue);
 		value |= MTL_RXQ_DMA_QXMDMACH(chan, queue);
-- 
2.25.1

