# CVE-2025-40012: linux: In the Linux kernel, the following vulnerability has been resolved:  net/smc: fix warning in smc_rx_splice() when cal...

CVE-2025-40012 is fixed in 18 products on 1 platform, first by DEBIAN-CVE-2025-40012, released October 20, 2025. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2025-40012
- Priority: High
- CVSS: 7.8 (high)
- EPSS: 0.0019
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 20, 2025

## Description

In the Linux kernel, the following vulnerability has been resolved:  net/smc: fix warning in smc_rx_splice() when calling get_page()  smc_lo_register_dmb() allocates DMB buffers with kzalloc(), which are later passed to get_page() in smc_rx_splice(). Since kmalloc memory is not page-backed, this triggers WARN_ON_ONCE() in get_page() and prevents holding a refcount on the buffer. This can lead to use-after-free if the memory is released before splice_to_pipe() completes.  Use folio_alloc() instead, ensuring DMBs are page-backed and safe for get_page().  WARNING: CPU: 18 PID: 12152 at ./include/linux/mm.h:1330 smc_rx_splice+0xaf8/0xe20 [smc] CPU: 18 UID: 0 PID: 12152 Comm: smcapp Kdump: loaded Not tainted 6.17.0-rc3-11705-g9cf4672ecfee #10 NONE Hardware name: IBM 3931 A01 704 (z/VM 7.4.0) Krnl PSW : 0704e00180000000 000793161032696c (smc_rx_splice+0xafc/0xe20 [smc])            R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3 Krnl GPRS: 0000000000000000 001cee80007d3001 00077400000000f8 0000000000000005            0000000000000001 001cee80007d3006 0007740000001000 001c000000000000            000000009b0c99e0 0000000000001000 001c0000000000f8 001c000000000000            000003ffcc6f7c88 0007740003e98000 0007931600000005 000792969b2ff7b8 Krnl Code: 0007931610326960: af000000		mc	0,0            0007931610326964: a7f4ff43		brc	15,00079316103267ea           #0007931610326968: af000000		mc	0,0           >000793161032696c: a7f4ff3f		brc	15,00079316103267ea            0007931610326970: e320f1000004	lg	%r2,256(%r15)            0007931610326976: c0e53fd1b5f5	brasl	%r14,000793168fd5d560            000793161032697c: a7f4fbb5		brc	15,00079316103260e6            0007931610326980: b904002b		lgr	%r2,%r11 Call Trace:  smc_rx_splice+0xafc/0xe20 [smc]  smc_rx_splice+0x756/0xe20 [smc])  smc_rx_recvmsg+0xa74/0xe00 [smc]  smc_splice_read+0x1ce/0x3b0 [smc]  sock_splice_read+0xa2/0xf0  do_splice_read+0x198/0x240  splice_file_to_pipe+0x7e/0x110  do_splice+0x59e/0xde0  __do_splice+0x11a/0x2d0  __s390x_sys_splice+0x140/0x1f0  __do_syscall+0x122/0x280  system_call+0x6e/0x90 Last Breaking-Event-Address: smc_rx_splice+0x960/0xe20 [smc] ---[ end trace 0000000000000000 ]---

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | dtb-aarch64 opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-64kb opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-64kb sles 15.7 | 6.4.0-150700.53.22.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-64kb sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-azure sles 15.7 | 6.4.0-150700.20.18.1 | [SUSE-SU-2025:4132-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4132-1.md) | Nov 18, 2025 |
| Linux | kernel-default opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-default sles 15.7 | 6.4.0-150700.53.22.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-default sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-default-base opensuse-leap 16.0 | 6.12.0-160000.6.1.160000.2.4 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-default-base sles 15.7 | 6.4.0-150700.53.22.1.150700.17.15.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-default-base sles 16.0 | 6.12.0-160000.6.1.160000.2.4 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-docs opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-docs sles 15.7 | 6.4.0-150700.53.22.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-docs sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-kvmsmall opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-kvmsmall sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-livepatch-SLE15-SP7-RT_Update_6 sles 15.7 | 1-150700.1.3.1 | [SUSE-SU-2025:4141-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4141-1.md) | Nov 19, 2025 |
| Linux | kernel-livepatch-SLE15-SP7_Update_6 sles 15.7 | 1-150700.15.3.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-obs-build opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-obs-build sles 15.7 | 6.4.0-150700.53.22.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-obs-qa opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-obs-qa sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-rt opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-source opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-source sles 15.7 | 6.4.0-150700.53.22.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-source sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-source-azure sles 15.7 | 6.4.0-150700.20.18.1 | [SUSE-SU-2025:4132-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4132-1.md) | Nov 18, 2025 |
| Linux | kernel-syms opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-syms sles 15.7 | 6.4.0-150700.53.22.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-syms sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | kernel-syms-azure sles 15.7 | 6.4.0-150700.20.18.1 | [SUSE-SU-2025:4132-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4132-1.md) | Nov 18, 2025 |
| Linux | kernel-zfcpdump opensuse-leap 16.0 | 6.12.0-160000.7.1 | [OPENSUSE-SU-2025:20091-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2025-20091-1.md) | Nov 26, 2025 |
| Linux | kernel-zfcpdump sles 15.7 | 6.4.0-150700.53.22.1 | [SUSE-SU-2025:4057-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-4057-1.md) | Nov 11, 2025 |
| Linux | kernel-zfcpdump sles 16.0 | 6.12.0-160000.7.1 | [SUSE-SU-2025:21147-1](https://patchblox.com/security/data/fix/linux/suse-su-2025-21147-1.md) | Nov 26, 2025 |
| Linux | linux Debian 13.5 (trixie) | 6.12.57-1 | [DEBIAN-CVE-2025-40012](https://patchblox.com/security/data/fix/linux/debian-cve-2025-40012.md) | Oct 20, 2025 |
| Linux | linux Debian 14 | 6.16.10-1 | [DEBIAN-CVE-2025-40012](https://patchblox.com/security/data/fix/linux/debian-cve-2025-40012.md) | Oct 20, 2025 |

---

Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

Free to use with attribution: show "Data: Patchblox Patch Radar" with a link to https://patchblox.com/security/patch-radar. Terms, including what needs a written agreement: https://patchblox.com/security/patch-radar/use-the-data

Product names, logos and trademarks shown on Patch Radar belong to their respective owners. They are used only to identify the software each security fix applies to and to help readers find their platform. Their use does not imply any affiliation with, or endorsement by, those owners, and Patchblox is not affiliated with any of them.
