Vulnerability CVE-2021-47456

Vulnerability CVE-2021-47456

Published: 2024-05-22

Description:

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

can: peak_pci: peak_pci_remove(): fix UAF

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

References:

https://git.kernel.org/stable/c/1c616528ba4aeb1125a06b407572ab7b56acae38

https://git.kernel.org/stable/c/447d44cd2f67a20b596ede3ca3cd67086dfd9ca9

https://git.kernel.org/stable/c/34914971bb3244db4ce2be44e9438a9b30c56250

https://git.kernel.org/stable/c/adbda14730aacce41c0d3596415aa39ad63eafd9

https://git.kernel.org/stable/c/1248582e47a9f7ce0ecd156c39fc61f8b6aa3699

https://git.kernel.org/stable/c/28f28e4bc3a5e0051faa963f10b778ab38c1db69

https://git.kernel.org/stable/c/0e5afdc2315b0737edcf55bede4ee1640d2d464d

https://git.kernel.org/stable/c/949fe9b35570361bc6ee2652f89a0561b26eec98

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