Description

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

media: mediatek: vcodec: Fix oops when HEVC init fails

The stateless HEVC decoder saves the instance pointer in the context
regardless if the initialization worked or not. This caused a use after
free, when the pointer is freed in case of a failure in the deinit
function.
Only store the instance pointer when the initialization was successful,
to solve this issue.

Hardware name: Acer Tomato (rev3 - 4) board (DT)
pstate: 80400009 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec]
lr : vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec]
sp : ffff80008750bc20
x29: ffff80008750bc20 x28: ffff1299f6d70000 x27: 0000000000000000
x26: 0000000000000000 x25: 0000000000000000 x24: 0000000000000000
x23: ffff80008750bc98 x22: 000000000000a003 x21: ffffd45c4cfae000
x20: 0000000000000010 x19: ffff1299fd668310 x18: 000000000000001a
x17: 000000040044ffff x16: ffffd45cb15dc648 x15: 0000000000000000
x14: ffff1299c08da1c0 x13: ffffd45cb1f87a10 x12: ffffd45cb2f5fe80
x11: 0000000000000001 x10: 0000000000001b30 x9 : ffffd45c4d12b488
x8 : 1fffe25339380d81 x7 : 0000000000000001 x6 : ffff1299c9c06c00
x5 : 0000000000000132 x4 : 0000000000000000 x3 : 0000000000000000
x2 : 0000000000000010 x1 : ffff80008750bc98 x0 : 0000000000000000
Call trace:
vcodec_vpu_send_msg+0x4c/0x190 [mtk_vcodec_dec]
vcodec_send_ap_ipi+0x78/0x170 [mtk_vcodec_dec]
vpu_dec_deinit+0x1c/0x30 [mtk_v...

Classification

CVE ID: CVE-2024-35921

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.04% (probability of being exploited)

EPSS Percentile: 5.08% (scored less or equal to compared to others)

EPSS Date: 2025-02-04 (when was this score calculated)

References

https://git.kernel.org/stable/c/ec25fc3c2c1e8958a51abcfed614f81446d918c4
https://git.kernel.org/stable/c/521ce0ea7418298d754494fe53263c23c4c78a8e
https://git.kernel.org/stable/c/97c75ee5de060d271d80109b0c47cb6008439e5b

Timeline