Description

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

powerpc64/ftrace: fix clobbered r15 during livepatching

While r15 is clobbered always with PPC_FTRACE_OUT_OF_LINE, it is
not restored in livepatch sequence leading to not so obvious fails
like below:

BUG: Unable to handle kernel data access on write at 0xc0000000000f9078
Faulting instruction address: 0xc0000000018ff958
Oops: Kernel access of bad area, sig: 11 [#1]
...
NIP: c0000000018ff958 LR: c0000000018ff930 CTR: c0000000009c0790
REGS: c00000005f2e7790 TRAP: 0300 Tainted: G K (6.14.0+)
MSR: 8000000000009033 CR: 2822880b XER: 20040000
CFAR: c0000000008addc0 DAR: c0000000000f9078 DSISR: 0a000000 IRQMASK: 1
GPR00: c0000000018f2584 c00000005f2e7a30 c00000000280a900 c000000017ffa488
GPR04: 0000000000000008 0000000000000000 c0000000018f24fc 000000000000000d
GPR08: fffffffffffe0000 000000000000000d 0000000000000000 0000000000008000
GPR12: c0000000009c0790 c000000017ffa480 c00000005f2e7c78 c0000000000f9070
GPR16: c00000005f2e7c90 0000000000000000 0000000000000000 0000000000000000
GPR20: 0000000000000000 c00000005f3efa80 c00000005f2e7c60 c00000005f2e7c88
GPR24: c00000005f2e7c60 0000000000000001 c0000000000f9078 0000000000000000
GPR28: 00007fff97960000 c000000017ffa480 0000000000000000 c0000000000f9078
...
Call Trace:
check_heap_object+0x34/0x390 (unreliable)
__mutex_unlock_slowpath.isra.0+0xe4/0x230
seq_read_iter+0x430/0xa90
proc_reg_read_i...

Classification

CVE ID: CVE-2025-38233

Affected Products

Vendor: Linux

Product: Linux

Exploit Prediction Scoring System (EPSS)

EPSS Score: 0.02% (probability of being exploited)

EPSS Percentile: 3.04% (scored less or equal to compared to others)

EPSS Date: 2025-07-06 (when was this score calculated)

References

https://nvd.nist.gov/vuln/detail/CVE-2025-38233
https://git.kernel.org/stable/c/a9212bf5ca640232254b31330e86272fe4073bc9
https://git.kernel.org/stable/c/cb5b691f8273432297611863ac142e17119279e0

Timeline