ghsa-p4m8-c64v-m3v8
Vulnerability from github
In the Linux kernel, the following vulnerability has been resolved:
powerpc/code-patching: Disable KASAN report during patching via temporary mm
Erhard reports the following KASAN hit on Talos II (power9) with kernel 6.13:
[ 12.028126] ================================================================== [ 12.028198] BUG: KASAN: user-memory-access in copy_to_kernel_nofault+0x8c/0x1a0 [ 12.028260] Write of size 8 at addr 0000187e458f2000 by task systemd/1
[ 12.028346] CPU: 87 UID: 0 PID: 1 Comm: systemd Tainted: G T 6.13.0-P9-dirty #3 [ 12.028408] Tainted: [T]=RANDSTRUCT [ 12.028446] Hardware name: T2P9D01 REV 1.01 POWER9 0x4e1202 opal:skiboot-bc106a0 PowerNV [ 12.028500] Call Trace: [ 12.028536] [c000000008dbf3b0] [c000000001656a48] dump_stack_lvl+0xbc/0x110 (unreliable) [ 12.028609] [c000000008dbf3f0] [c0000000006e2fc8] print_report+0x6b0/0x708 [ 12.028666] [c000000008dbf4e0] [c0000000006e2454] kasan_report+0x164/0x300 [ 12.028725] [c000000008dbf600] [c0000000006e54d4] kasan_check_range+0x314/0x370 [ 12.028784] [c000000008dbf640] [c0000000006e6310] __kasan_check_write+0x20/0x40 [ 12.028842] [c000000008dbf660] [c000000000578e8c] copy_to_kernel_nofault+0x8c/0x1a0 [ 12.028902] [c000000008dbf6a0] [c0000000000acfe4] __patch_instructions+0x194/0x210 [ 12.028965] [c000000008dbf6e0] [c0000000000ade80] patch_instructions+0x150/0x590 [ 12.029026] [c000000008dbf7c0] [c0000000001159bc] bpf_arch_text_copy+0x6c/0xe0 [ 12.029085] [c000000008dbf800] [c000000000424250] bpf_jit_binary_pack_finalize+0x40/0xc0 [ 12.029147] [c000000008dbf830] [c000000000115dec] bpf_int_jit_compile+0x3bc/0x930 [ 12.029206] [c000000008dbf990] [c000000000423720] bpf_prog_select_runtime+0x1f0/0x280 [ 12.029266] [c000000008dbfa00] [c000000000434b18] bpf_prog_load+0xbb8/0x1370 [ 12.029324] [c000000008dbfb70] [c000000000436ebc] __sys_bpf+0x5ac/0x2e00 [ 12.029379] [c000000008dbfd00] [c00000000043a228] sys_bpf+0x28/0x40 [ 12.029435] [c000000008dbfd20] [c000000000038eb4] system_call_exception+0x334/0x610 [ 12.029497] [c000000008dbfe50] [c00000000000c270] system_call_vectored_common+0xf0/0x280 [ 12.029561] --- interrupt: 3000 at 0x3fff82f5cfa8 [ 12.029608] NIP: 00003fff82f5cfa8 LR: 00003fff82f5cfa8 CTR: 0000000000000000 [ 12.029660] REGS: c000000008dbfe80 TRAP: 3000 Tainted: G T (6.13.0-P9-dirty) [ 12.029735] MSR: 900000000280f032 CR: 42004848 XER: 00000000 [ 12.029855] IRQMASK: 0 GPR00: 0000000000000169 00003fffdcf789a0 00003fff83067100 0000000000000005 GPR04: 00003fffdcf78a98 0000000000000090 0000000000000000 0000000000000008 GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR12: 0000000000000000 00003fff836ff7e0 c000000000010678 0000000000000000 GPR16: 0000000000000000 0000000000000000 00003fffdcf78f28 00003fffdcf78f90 GPR20: 0000000000000000 0000000000000000 0000000000000000 00003fffdcf78f80 GPR24: 00003fffdcf78f70 00003fffdcf78d10 00003fff835c7239 00003fffdcf78bd8 GPR28: 00003fffdcf78a98 0000000000000000 0000000000000000 000000011f547580 [ 12.030316] NIP [00003fff82f5cfa8] 0x3fff82f5cfa8 [ 12.030361] LR [00003fff82f5cfa8] 0x3fff82f5cfa8 [ 12.030405] --- interrupt: 3000 [ 12.030444] ==================================================================
Commit c28c15b6d28a ("powerpc/code-patching: Use temporary mm for Radix MMU") is inspired from x86 but unlike x86 is doesn't disable KASAN reports during patching. This wasn't a problem at the begining because __patch_mem() is not instrumented.
Commit 465cabc97b42 ("powerpc/code-patching: introduce patch_instructions()") use copy_to_kernel_nofault() to copy several instructions at once. But when using temporary mm the destination is not regular kernel memory but a kind of kernel-like memory located in user address space. ---truncated---
{
"affected": [],
"aliases": [
"CVE-2025-21869"
],
"database_specific": {
"cwe_ids": [],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2025-03-27T14:15:48Z",
"severity": null
},
"details": "In the Linux kernel, the following vulnerability has been resolved:\n\npowerpc/code-patching: Disable KASAN report during patching via temporary mm\n\nErhard reports the following KASAN hit on Talos II (power9) with kernel 6.13:\n\n[ 12.028126] ==================================================================\n[ 12.028198] BUG: KASAN: user-memory-access in copy_to_kernel_nofault+0x8c/0x1a0\n[ 12.028260] Write of size 8 at addr 0000187e458f2000 by task systemd/1\n\n[ 12.028346] CPU: 87 UID: 0 PID: 1 Comm: systemd Tainted: G T 6.13.0-P9-dirty #3\n[ 12.028408] Tainted: [T]=RANDSTRUCT\n[ 12.028446] Hardware name: T2P9D01 REV 1.01 POWER9 0x4e1202 opal:skiboot-bc106a0 PowerNV\n[ 12.028500] Call Trace:\n[ 12.028536] [c000000008dbf3b0] [c000000001656a48] dump_stack_lvl+0xbc/0x110 (unreliable)\n[ 12.028609] [c000000008dbf3f0] [c0000000006e2fc8] print_report+0x6b0/0x708\n[ 12.028666] [c000000008dbf4e0] [c0000000006e2454] kasan_report+0x164/0x300\n[ 12.028725] [c000000008dbf600] [c0000000006e54d4] kasan_check_range+0x314/0x370\n[ 12.028784] [c000000008dbf640] [c0000000006e6310] __kasan_check_write+0x20/0x40\n[ 12.028842] [c000000008dbf660] [c000000000578e8c] copy_to_kernel_nofault+0x8c/0x1a0\n[ 12.028902] [c000000008dbf6a0] [c0000000000acfe4] __patch_instructions+0x194/0x210\n[ 12.028965] [c000000008dbf6e0] [c0000000000ade80] patch_instructions+0x150/0x590\n[ 12.029026] [c000000008dbf7c0] [c0000000001159bc] bpf_arch_text_copy+0x6c/0xe0\n[ 12.029085] [c000000008dbf800] [c000000000424250] bpf_jit_binary_pack_finalize+0x40/0xc0\n[ 12.029147] [c000000008dbf830] [c000000000115dec] bpf_int_jit_compile+0x3bc/0x930\n[ 12.029206] [c000000008dbf990] [c000000000423720] bpf_prog_select_runtime+0x1f0/0x280\n[ 12.029266] [c000000008dbfa00] [c000000000434b18] bpf_prog_load+0xbb8/0x1370\n[ 12.029324] [c000000008dbfb70] [c000000000436ebc] __sys_bpf+0x5ac/0x2e00\n[ 12.029379] [c000000008dbfd00] [c00000000043a228] sys_bpf+0x28/0x40\n[ 12.029435] [c000000008dbfd20] [c000000000038eb4] system_call_exception+0x334/0x610\n[ 12.029497] [c000000008dbfe50] [c00000000000c270] system_call_vectored_common+0xf0/0x280\n[ 12.029561] --- interrupt: 3000 at 0x3fff82f5cfa8\n[ 12.029608] NIP: 00003fff82f5cfa8 LR: 00003fff82f5cfa8 CTR: 0000000000000000\n[ 12.029660] REGS: c000000008dbfe80 TRAP: 3000 Tainted: G T (6.13.0-P9-dirty)\n[ 12.029735] MSR: 900000000280f032 \u003cSF,HV,VEC,VSX,EE,PR,FP,ME,IR,DR,RI\u003e CR: 42004848 XER: 00000000\n[ 12.029855] IRQMASK: 0\n GPR00: 0000000000000169 00003fffdcf789a0 00003fff83067100 0000000000000005\n GPR04: 00003fffdcf78a98 0000000000000090 0000000000000000 0000000000000008\n GPR08: 0000000000000000 0000000000000000 0000000000000000 0000000000000000\n GPR12: 0000000000000000 00003fff836ff7e0 c000000000010678 0000000000000000\n GPR16: 0000000000000000 0000000000000000 00003fffdcf78f28 00003fffdcf78f90\n GPR20: 0000000000000000 0000000000000000 0000000000000000 00003fffdcf78f80\n GPR24: 00003fffdcf78f70 00003fffdcf78d10 00003fff835c7239 00003fffdcf78bd8\n GPR28: 00003fffdcf78a98 0000000000000000 0000000000000000 000000011f547580\n[ 12.030316] NIP [00003fff82f5cfa8] 0x3fff82f5cfa8\n[ 12.030361] LR [00003fff82f5cfa8] 0x3fff82f5cfa8\n[ 12.030405] --- interrupt: 3000\n[ 12.030444] ==================================================================\n\nCommit c28c15b6d28a (\"powerpc/code-patching: Use temporary mm for\nRadix MMU\") is inspired from x86 but unlike x86 is doesn\u0027t disable\nKASAN reports during patching. This wasn\u0027t a problem at the begining\nbecause __patch_mem() is not instrumented.\n\nCommit 465cabc97b42 (\"powerpc/code-patching: introduce\npatch_instructions()\") use copy_to_kernel_nofault() to copy several\ninstructions at once. But when using temporary mm the destination is\nnot regular kernel memory but a kind of kernel-like memory located\nin user address space. \n---truncated---",
"id": "GHSA-p4m8-c64v-m3v8",
"modified": "2025-03-27T15:31:08Z",
"published": "2025-03-27T15:31:08Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-21869"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/5980d4456dd66d1b6505d5ec15048bd87e8775e0"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/dc9c5166c3cb044f8a001e397195242fd6796eee"
},
{
"type": "WEB",
"url": "https://git.kernel.org/stable/c/ea291447a4031f3dac5c23d55bc83fe833820d84"
}
],
"schema_version": "1.4.0",
"severity": []
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.