On 14.10.2021 06:28:33, Zheyu Ma wrote:

When remove the module peek_pci, referencing 'chan' again after
releasing 'dev' will cause UAF.

Fix this by releasing 'dev' later.

The following log reveals it:

[   35.961814 ] BUG: KASAN: use-after-free in peak_pci_remove+0x16f/0x270 [peak_pci]
[   35.963414 ] Read of size 8 at addr ffff888136998ee8 by task modprobe/5537
[   35.965513 ] Call Trace:
[   35.965718 ]  dump_stack_lvl+0xa8/0xd1
[   35.966028 ]  print_address_description+0x87/0x3b0
[   35.966420 ]  kasan_report+0x172/0x1c0
[   35.966725 ]  ? peak_pci_remove+0x16f/0x270 [peak_pci]
[   35.967137 ]  ? trace_irq_enable_rcuidle+0x10/0x170
[   35.967529 ]  ? peak_pci_remove+0x16f/0x270 [peak_pci]
[   35.967945 ]  __asan_report_load8_noabort+0x14/0x20
[   35.968346 ]  peak_pci_remove+0x16f/0x270 [peak_pci]
[   35.968752 ]  pci_device_remove+0xa9/0x250

Signed-off-by: Zheyu Ma <redacted>

Applied to linux-can/testing.

Thanks,
Marc

-- 
Pengutronix e.K.                 | Marc Kleine-Budde           |
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