TLDRVuln - Cybersecurity Vulnerabilities Made Simple

In the Linux kernel, the following vulnerability has been resolved:

wifi: mt76: do not run mt76u_status_worker if the device is not running

Fix the following NULL pointer dereference avoiding to run

mt76u_status_worker thread if the device is not running yet.

KASAN: null-ptr-deref in range

[0x0000000000000000-0x0000000000000007]

CPU: 0 PID: 98 Comm: kworker/u2:2 Not tainted 5.14.0+ #78 Hardware

name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS

rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014

Workqueue: mt76 mt76u_tx_status_data

RIP: 0010:mt76x02_mac_fill_tx_status.isra.0+0x82c/0x9e0

Code: c5 48 b8 00 00 00 00 00 fc ff df 80 3c 02 00 0f 85 94 01 00 00

48 b8 00 00 00 00 00 fc ff df 4d 8b 34 24 4c 89 f2 48 c1 ea 03 <0f>

04 02 84 c0 74 08 3c 03 0f 8e 89 01 00 00 41 8b 16 41 0f b7

RSP: 0018:ffffc900005af988 EFLAGS: 00010246

RAX: dffffc0000000000 RBX: ffffc900005afae8 RCX: 0000000000000000

RDX: 0000000000000000 RSI: ffffffff832fc661 RDI: ffffc900005afc2a

RBP: ffffc900005afae0 R08: 0000000000000001 R09: fffff520000b5f3c

R10: 0000000000000003 R11: fffff520000b5f3b R12: ffff88810b6132d8

R13: 000000000000ffff R14: 0000000000000000 R15: ffffc900005afc28

FS: 0000000000000000(0000) GS:ffff88811aa00000(0000)

knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fa0eda6a000 CR3: 0000000118f17000 CR4: 0000000000750ef0

PKRU: 55555554

Call Trace:

mt76x02_send_tx_status+0x1d2/0xeb0

mt76x02_tx_status_data+0x8e/0xd0

mt76u_tx_status_data+0xe1/0x240

process_one_work+0x92b/0x1460

worker_thread+0x95/0xe00

kthread+0x3a1/0x480

ret_from_fork+0x1f/0x30

Modules linked in:

--[ end trace 8df5d20fc5040f65 ]--