[PATCH 5.16 037/285] mt76: dma: initialize skip_unmap in mt76_dma_rx_fill

Greg Kroah-Hartman
2022-04-12T07:43:14Z

From: Lorenzo Bianconi <lorenzo@kernel.org>

[ Upstream commit 577298ec55dfc8b9aece54520f0258c3f93a6573 ]

Even if it is only a false-positive since skip_buf0/skip_buf1 are only
used in mt76_dma_tx_cleanup_idx routine, initialize skip_unmap in
mt76_dma_rx_fill in order to fix the following UBSAN report:

[ 13.924906] UBSAN: invalid-load in linux-5.15.0/drivers/net/wireless/mediatek/mt76/dma.c:162:13
[ 13.924909] load of value 225 is not a valid value for type '_Bool'
[ 13.924912] CPU: 9 PID: 672 Comm: systemd-udevd Not tainted 5.15.0-18-generic #18-Ubuntu
[ 13.924914] Hardware name: LENOVO 21A0000CMX/21A0000CMX, BIOS R1MET43W (1.13 ) 11/05/2021
[ 13.924915] Call Trace:
[ 13.924917] <TASK>
[ 13.924920] show_stack+0x52/0x58
[ 13.924925] dump_stack_lvl+0x4a/0x5f
[ 13.924931] dump_stack+0x10/0x12
[ 13.924932] ubsan_epilogue+0x9/0x45
[ 13.924934] __ubsan_handle_load_invalid_value.cold+0x44/0x49
[ 13.924935] ? __iommu_dma_map+0x84/0xf0
[ 13.924939] mt76_dma_add_buf.constprop.0.cold+0x23/0x85 [mt76]
[ 13.924949] mt76_dma_rx_fill.isra.0+0x102/0x1f0 [mt76]
[ 13.924954] mt76_dma_init+0xc9/0x150 [mt76]
[ 13.924959] ? mt7921_dma_enable+0x110/0x110 [mt7921e]
[ 13.924966] mt7921_dma_init+0x1e3/0x260 [mt7921e]
[ 13.924970] mt7921_register_device+0x29d/0x510 [mt7921e]
[ 13.924975] mt7921_pci_probe.part.0+0x17f/0x1b0 [mt7921e]
[ 13.924980] mt7921_pci_probe+0x43/0x60 [mt7921e]
[ 13.924984] local_pci_probe+0x4b/0x90
[ 13.924987] pci_device_probe+0x115/0x1f0
[ 13.924989] really_probe+0x21e/0x420
[ 13.924992] __driver_probe_device+0x115/0x190
[ 13.924994] driver_probe_device+0x23/0xc0
[ 13.924996] __driver_attach+0xbd/0x1d0
[ 13.924998] ? __device_attach_driver+0x110/0x110
[ 13.924999] bus_for_each_dev+0x7e/0xc0
[ 13.925001] driver_attach+0x1e/0x20
[ 13.925003] bus_add_driver+0x135/0x200
[ 13.925005] driver_register+0x95/0xf0
[ 13.925008] ? 0xffffffffc0766000
[ 13.925010] __pci_register_driver+0x68/0x70
[ 13.925011] mt7921_pci_driver_init+0x23/0x1000 [mt7921e]
[ 13.925015] do_one_initcall+0x48/0x1d0
[ 13.925019] ? kmem_cache_alloc_trace+0x19e/0x2e0
[ 13.925022] do_init_module+0x62/0x280
[ 13.925025] load_module+0xac9/0xbb0
[ 13.925027] __do_sys_finit_module+0xbf/0x120
[ 13.925029] __x64_sys_finit_module+0x18/0x20
[ 13.925030] do_syscall_64+0x5c/0xc0
[ 13.925033] ? do_syscall_64+0x69/0xc0
[ 13.925034] ? sysvec_reschedule_ipi+0x78/0xe0
[ 13.925036] ? asm_sysvec_reschedule_ipi+0xa/0x20
[ 13.925039] entry_SYSCALL_64_after_hwframe+0x44/0xae
[ 13.925040] RIP: 0033:0x7fbf2b90f94d
[ 13.925045] RSP: 002b:00007ffe2ec7e5d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000139
[ 13.925047] RAX: ffffffffffffffda RBX: 000056106b0634e0 RCX: 00007fbf2b90f94d
[ 13.925048] RDX: 0000000000000000 RSI: 00007fbf2baa3441 RDI: 0000000000000013
[ 13.925049] RBP: 0000000000020000 R08: 0000000000000000 R09: 0000000000000002
[ 13.925050] R10: 0000000000000013 R11: 0000000000000246 R12: 00007fbf2baa3441
[ 13.925051] R13: 000056106b062620 R14: 000056106b0610c0 R15: 000056106b0640d0
[ 13.925053] </TASK>

Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/wireless/mediatek/mt76/dma.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/mediatek/mt76/dma.c b/drivers/net/wireless/mediatek/mt76/dma.c
index 5e1c1506a4c6..7aecde35cb9a 100644
--- a/drivers/net/wireless/mediatek/mt76/dma.c
+++ b/drivers/net/wireless/mediatek/mt76/dma.c
@@ -465,6 +465,7 @@ mt76_dma_rx_fill(struct mt76_dev *dev, struct mt76_queue *q)

qbuf.addr = addr + offset;
qbuf.len = len - offset;
+ qbuf.skip_unmap = false;
mt76_dma_add_buf(dev, q, &qbuf, 1, 0, buf, NULL);
frames++;
}
--
2.35.1