CVE-2025-39728: clk: samsung: Fix UBSAN panic in samsung_clk_init()

Description

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

clk: samsung: Fix UBSAN panic in samsung_clk_init()

With UBSAN_ARRAY_BOUNDS=y, I'm hitting the below panic due to
dereferencing `ctx->clk_data.hws` before setting
`ctx->clk_data.num = nr_clks`. Move that up to fix the crash.

UBSAN: array index out of bounds: 00000000f2005512 [#1] PREEMPT SMP

Call trace:
samsung_clk_init+0x110/0x124 (P)
samsung_clk_init+0x48/0x124 (L)
samsung_cmu_register_one+0x3c/0xa0
exynos_arm64_register_cmu+0x54/0x64
__gs101_cmu_top_of_clk_init_declare+0x28/0x60
...

Classification

CVE ID: CVE-2025-39728

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.02% (probability of being exploited)

EPSS Percentile: 5.06% (scored less or equal to compared to others)

EPSS Date: 2025-04-18 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-39728
https://git.kernel.org/stable/c/00307934eb94aaa0a99addfb37b9fe206f945004
https://git.kernel.org/stable/c/d974e177369c034984cece9d7d4fada9f8b9c740
https://git.kernel.org/stable/c/0fef48f4a70e45a93e73c39023c3a6ea624714d6
https://git.kernel.org/stable/c/4d29a6dcb51e346595a15b49693eeb728925ca43
https://git.kernel.org/stable/c/24307866e0ac0a5ddb462e766ceda5e27a6fbbe3
https://git.kernel.org/stable/c/a1500b98cd81a32fdfb9bc63c33bb9f0c2a0a1bf
https://git.kernel.org/stable/c/157de9e48007a20c65d02fc0229a16f38134a72d
https://git.kernel.org/stable/c/d19d7345a7bcdb083b65568a11b11adffe0687af

Timeline