wifi: mt76: mt7921s: fix slab-out-of-bounds access in sdio host
authorDeren Wu <deren.wu@mediatek.com>
Thu, 1 Dec 2022 15:53:37 +0000 (23:53 +0800)
committerFelix Fietkau <nbd@nbd.name>
Fri, 9 Dec 2022 15:45:38 +0000 (16:45 +0100)
commitaec4cf2ea0797e28f18f8dbe01943a56d987fe56
tree44fc8a605bb00f4b179c4a858e3f3246af9f1220
parent18425d7d74c5be88b13b970a21e52e2498abf4ba
wifi: mt76: mt7921s: fix slab-out-of-bounds access in sdio host

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 [ffff88811c9ce800ffff88811c9cf000)

[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>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
drivers/net/wireless/mediatek/mt76/sdio_txrx.c