diff mbox series

[v2] wifi: mt76: mt7921s: fix slab-out-of-bounds access in sdio host

Message ID 0cb01834f0cbcefddfd6facc27568178c139839e.1669909513.git.deren.wu@mediatek.com (mailing list archive)
State Accepted
Delegated to: Felix Fietkau
Headers show
Series [v2] wifi: mt76: mt7921s: fix slab-out-of-bounds access in sdio host | expand

Commit Message

Deren Wu Dec. 1, 2022, 3:53 p.m. UTC
SDIO may need addtional 511 bytes to align bus operation. If the tailroom
of this skb is not big enough, we would access invalid memory region.
For low level operation, increase skb size to keep valid memory access in
SDIO host.

Error message:
[69.951] BUG: KASAN: slab-out-of-bounds in sg_copy_buffer+0xe9/0x1a0
[69.951] Read of size 64 at addr ffff88811c9cf000 by task kworker/u16:7/451
[69.951] CPU: 4 PID: 451 Comm: kworker/u16:7 Tainted: G W  OE  6.1.0-rc5 #1
[69.951] Workqueue: kvub300c vub300_cmndwork_thread [vub300]
[69.951] Call Trace:
[69.951]  <TASK>
[69.952]  dump_stack_lvl+0x49/0x63
[69.952]  print_report+0x171/0x4a8
[69.952]  kasan_report+0xb4/0x130
[69.952]  kasan_check_range+0x149/0x1e0
[69.952]  memcpy+0x24/0x70
[69.952]  sg_copy_buffer+0xe9/0x1a0
[69.952]  sg_copy_to_buffer+0x12/0x20
[69.952]  __command_write_data.isra.0+0x23c/0xbf0 [vub300]
[69.952]  vub300_cmndwork_thread+0x17f3/0x58b0 [vub300]
[69.952]  process_one_work+0x7ee/0x1320
[69.952]  worker_thread+0x53c/0x1240
[69.952]  kthread+0x2b8/0x370
[69.952]  ret_from_fork+0x1f/0x30
[69.952]  </TASK>

[69.952] Allocated by task 854:
[69.952]  kasan_save_stack+0x26/0x50
[69.952]  kasan_set_track+0x25/0x30
[69.952]  kasan_save_alloc_info+0x1b/0x30
[69.952]  __kasan_kmalloc+0x87/0xa0
[69.952]  __kmalloc_node_track_caller+0x63/0x150
[69.952]  kmalloc_reserve+0x31/0xd0
[69.952]  __alloc_skb+0xfc/0x2b0
[69.952]  __mt76_mcu_msg_alloc+0xbf/0x230 [mt76]
[69.952]  mt76_mcu_send_and_get_msg+0xab/0x110 [mt76]
[69.952]  __mt76_mcu_send_firmware.cold+0x94/0x15d [mt76]
[69.952]  mt76_connac_mcu_send_ram_firmware+0x415/0x54d [mt76_connac_lib]
[69.952]  mt76_connac2_load_ram.cold+0x118/0x4bc [mt76_connac_lib]
[69.952]  mt7921_run_firmware.cold+0x2e9/0x405 [mt7921_common]
[69.952]  mt7921s_mcu_init+0x45/0x80 [mt7921s]
[69.953]  mt7921_init_work+0xe1/0x2a0 [mt7921_common]
[69.953]  process_one_work+0x7ee/0x1320
[69.953]  worker_thread+0x53c/0x1240
[69.953]  kthread+0x2b8/0x370
[69.953]  ret_from_fork+0x1f/0x30
[69.953] The buggy address belongs to the object at ffff88811c9ce800
             which belongs to the cache kmalloc-2k of size 2048
[69.953] The buggy address is located 0 bytes to the right of
             2048-byte region [ffff88811c9ce800, ffff88811c9cf000)

[69.953] Memory state around the buggy address:
[69.953]  ffff88811c9cef00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[69.953]  ffff88811c9cef80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[69.953] >ffff88811c9cf000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[69.953]                    ^
[69.953]  ffff88811c9cf080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[69.953]  ffff88811c9cf100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

Fixes: 764dee47e2c1 ("mt76: sdio: move common code in mt76_sdio module")
Suggested-by: Lorenzo Bianconi <lorenzo@kernel.org>
Tested-by: YN Chen <YN.Chen@mediatek.com>
Signed-off-by: Deren Wu <deren.wu@mediatek.com>
---
v2:
  - use __skb_grow to increase skb size
  - add suggested by Lorenzo
---
 drivers/net/wireless/mediatek/mt76/sdio_txrx.c | 4 ++++
 1 file changed, 4 insertions(+)
diff mbox series

Patch

diff --git a/drivers/net/wireless/mediatek/mt76/sdio_txrx.c b/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
index bfc4de50a4d2..ddd8c0cc744d 100644
--- a/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
+++ b/drivers/net/wireless/mediatek/mt76/sdio_txrx.c
@@ -254,6 +254,10 @@  static int mt76s_tx_run_queue(struct mt76_dev *dev, struct mt76_queue *q)
 
 		if (!test_bit(MT76_STATE_MCU_RUNNING, &dev->phy.state)) {
 			__skb_put_zero(e->skb, 4);
+			err = __skb_grow(e->skb, roundup(e->skb->len,
+							 sdio->func->cur_blksize));
+			if (err)
+				return err;
 			err = __mt76s_xmit_queue(dev, e->skb->data,
 						 e->skb->len);
 			if (err)