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 <SF,EE,ME,IR,DR,RI,LE> 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_iter+0xa4/0x200 vfs_read+0x41c/0x510 ksys_read+0xa4/0x190 system_call_exception+0x1d0/0x440 system_call_vectored_common+0x15c/0x2ec Fix it by restoring r15 always.
History

Sun, 06 Jul 2025 12:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

cvssV3_1

{'score': 5.5, 'vector': 'CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}

threat_severity

Moderate


Fri, 04 Jul 2025 13:45:00 +0000

Type Values Removed Values Added
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 <SF,EE,ME,IR,DR,RI,LE> 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_iter+0xa4/0x200 vfs_read+0x41c/0x510 ksys_read+0xa4/0x190 system_call_exception+0x1d0/0x440 system_call_vectored_common+0x15c/0x2ec Fix it by restoring r15 always.
Title powerpc64/ftrace: fix clobbered r15 during livepatching
References

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2025-07-04T13:37:46.293Z

Updated: 2025-07-04T13:37:46.293Z

Reserved: 2025-04-16T04:51:23.996Z

Link: CVE-2025-38233

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2025-07-04T14:15:32.953

Modified: 2025-07-08T16:18:53.607

Link: CVE-2025-38233

cve-icon Redhat

Severity : Moderate

Publid Date: 2025-07-04T00:00:00Z

Links: CVE-2025-38233 - Bugzilla