CVE-2025-40012
Full vulnerability record from the local CVENow database.
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 ]---
View original CVE JSON
{
"id": "CVE-2025-40012",
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"published": "2025-10-20T16:15:37.937",
"lastModified": "2026-10-19T21:10:00.160",
"vulnStatus": "Deferred",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/smc: fix warning in smc_rx_splice() when calling get_page()\n\nsmc_lo_register_dmb() allocates DMB buffers with kzalloc(), which are\nlater passed to get_page() in smc_rx_splice(). Since kmalloc memory is\nnot page-backed, this triggers WARN_ON_ONCE() in get_page() and prevents\nholding a refcount on the buffer. This can lead to use-after-free if\nthe memory is released before splice_to_pipe() completes.\n\nUse folio_alloc() instead, ensuring DMBs are page-backed and safe for\nget_page().\n\nWARNING: CPU: 18 PID: 12152 at ./include/linux/mm.h:1330 smc_rx_splice+0xaf8/0xe20 [smc]\nCPU: 18 UID: 0 PID: 12152 Comm: smcapp Kdump: loaded Not tainted 6.17.0-rc3-11705-g9cf4672ecfee #10 NONE\nHardware name: IBM 3931 A01 704 (z/VM 7.4.0)\nKrnl PSW : 0704e00180000000 000793161032696c (smc_rx_splice+0xafc/0xe20 [smc])\n 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\nKrnl GPRS: 0000000000000000 001cee80007d3001 00077400000000f8 0000000000000005\n 0000000000000001 001cee80007d3006 0007740000001000 001c000000000000\n 000000009b0c99e0 0000000000001000 001c0000000000f8 001c000000000000\n 000003ffcc6f7c88 0007740003e98000 0007931600000005 000792969b2ff7b8\nKrnl Code: 0007931610326960: af000000\t\tmc\t0,0\n 0007931610326964: a7f4ff43\t\tbrc\t15,00079316103267ea\n #0007931610326968: af000000\t\tmc\t0,0\n >000793161032696c: a7f4ff3f\t\tbrc\t15,00079316103267ea\n 0007931610326970: e320f1000004\tlg\t%r2,256(%r15)\n 0007931610326976: c0e53fd1b5f5\tbrasl\t%r14,000793168fd5d560\n 000793161032697c: a7f4fbb5\t\tbrc\t15,00079316103260e6\n 0007931610326980: b904002b\t\tlgr\t%r2,%r11\nCall Trace:\n smc_rx_splice+0xafc/0xe20 [smc]\n smc_rx_splice+0x756/0xe20 [smc])\n smc_rx_recvmsg+0xa74/0xe00 [smc]\n smc_splice_read+0x1ce/0x3b0 [smc]\n sock_splice_read+0xa2/0xf0\n do_splice_read+0x198/0x240\n splice_file_to_pipe+0x7e/0x110\n do_splice+0x59e/0xde0\n __do_splice+0x11a/0x2d0\n __s390x_sys_splice+0x140/0x1f0\n __do_syscall+0x122/0x280\n system_call+0x6e/0x90\nLast Breaking-Event-Address:\nsmc_rx_splice+0x960/0xe20 [smc]\n---[ end trace 0000000000000000 ]---"
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet/smc: corregir advertencia en smc_rx_splice() al llamar a get_page()\n\nsmc_lo_register_dmb() asigna búferes DMB con kzalloc(), que luego se pasan a get_page() en smc_rx_splice(). Dado que la memoria kmalloc no está respaldada por páginas, esto activa WARN_ON_ONCE() en get_page() y evita mantener un recuento de referencias en el búfer. Esto puede llevar a un uso después de liberación si la memoria se libera antes de que splice_to_pipe() se complete.\n\nUsar folio_alloc() en su lugar, asegurando que los DMB estén respaldados por páginas y sean seguros para get_page().\n\nADVERTENCIA: CPU: 18 PID: 12152 en ./include/linux/mm.h:1330 smc_rx_splice+0xaf8/0xe20 [smc]\nCPU: 18 UID: 0 PID: 12152 Comando: smcapp Kdump: cargado No contaminado 6.17.0-rc3-11705-g9cf4672ecfee #10 NINGUNO\nNombre del hardware: IBM 3931 A01 704 (z/VM 7.4.0)\nPSW del kernel: 0704e00180000000 000793161032696c (smc_rx_splice+0xafc/0xe20 [smc])\n 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\nGPRS del kernel: 0000000000000000 001cee80007d3001 00077400000000f8 0000000000000005\n 0000000000000001 001cee80007d3006 0007740000001000 001c000000000000\n 000000009b0c99e0 0000000000001000 001c0000000000f8 001c000000000000\n 000003ffcc6f7c88 0007740003e98000 0007931600000005 000792969b2ff7b8\nCódigo del kernel: 0007931610326960: af000000\t\tmc\t0,0\n 0007931610326964: a7f4ff43\t\tbrc\t15,00079316103267ea\n #0007931610326968: af000000\t\tmc\t0,0\n >000793161032696c: a7f4ff3f\t\tbrc\t15,00079316103267ea\n 0007931610326970: e320f1000004\tlg\t%r2,256(%r15)\n 0007931610326976: c0e53fd1b5f5\tbrasl\t%r14,000793168fd5d560\n 000793161032697c: a7f4fbb5\t\tbrc\t15,00079316103260e6\n 0007931610326980: b904002b\t\tlgr\t%r2,%r11\nTraza de llamadas:\n smc_rx_splice+0xafc/0xe20 [smc]\n smc_rx_splice+0x756/0xe20 [smc])\n smc_rx_recvmsg+0xa74/0xe00 [smc]\n smc_splice_read+0x1ce/0x3b0 [smc]\n sock_splice_read+0xa2/0xf0\n do_splice_read+0x198/0x240\n splice_file_to_pipe+0x7e/0x110\n do_splice+0x59e/0xde0\n __do_splice+0x11a/0x2d0\n __s390x_sys_splice+0x140/0x1f0\n __do_syscall+0x122/0x280\n system_call+0x6e/0x90\nÚltima dirección de evento de interrupción:\nsmc_rx_splice+0x960/0xe20 [smc]\n---[ fin de la traza 0000000000000000 ]---"
}
],
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "unaffected",
"programFiles": [
"net/smc/smc_loopback.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "f7a22071dbf316c982fb44308874bd7ad9ac2091",
"lessThan": "14fc4fdae42e34d7ee871b292ac2ecc61c2c5de7",
"versionType": "git",
"status": "affected"
},
{
"version": "f7a22071dbf316c982fb44308874bd7ad9ac2091",
"lessThan": "d5411685dc2f6ac7bdf01a0a204d56cae38c6cf6",
"versionType": "git",
"status": "affected"
},
{
"version": "f7a22071dbf316c982fb44308874bd7ad9ac2091",
"lessThan": "a35c04de2565db191726b5741e6b66a35002c652",
"versionType": "git",
"status": "affected"
}
]
},
{
"vendor": "Linux",
"product": "Linux",
"defaultStatus": "affected",
"programFiles": [
"net/smc/smc_loopback.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"versions": [
{
"version": "6.10",
"status": "affected"
},
{
"version": "0",
"lessThan": "6.10",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.12.50",
"lessThanOrEqual": "6.12.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.16.10",
"lessThanOrEqual": "6.16.*",
"versionType": "semver",
"status": "unaffected"
},
{
"version": "6.17",
"lessThanOrEqual": "*",
"versionType": "original_commit_for_fix",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "LOW",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9
}
]
},
"references": [
{
"url": "https://git.kernel.org/stable/c/14fc4fdae42e34d7ee871b292ac2ecc61c2c5de7",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/a35c04de2565db191726b5741e6b66a35002c652",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/d5411685dc2f6ac7bdf01a0a204d56cae38c6cf6",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
]
}