CVE-2025-38475 (GCVE-0-2025-38475)

Vulnerability from cvelistv5 – Published: 2025-07-28 11:21 – Updated: 2025-07-28 11:21
VLAI?
Title
smc: Fix various oops due to inet_sock type confusion.
Summary
In the Linux kernel, the following vulnerability has been resolved: smc: Fix various oops due to inet_sock type confusion. syzbot reported weird splats [0][1] in cipso_v4_sock_setattr() while freeing inet_sk(sk)->inet_opt. The address was freed multiple times even though it was read-only memory. cipso_v4_sock_setattr() did nothing wrong, and the root cause was type confusion. The cited commit made it possible to create smc_sock as an INET socket. The issue is that struct smc_sock does not have struct inet_sock as the first member but hijacks AF_INET and AF_INET6 sk_family, which confuses various places. In this case, inet_sock.inet_opt was actually smc_sock.clcsk_data_ready(), which is an address of a function in the text segment. $ pahole -C inet_sock vmlinux struct inet_sock { ... struct ip_options_rcu * inet_opt; /* 784 8 */ $ pahole -C smc_sock vmlinux struct smc_sock { ... void (*clcsk_data_ready)(struct sock *); /* 784 8 */ The same issue for another field was reported before. [2][3] At that time, an ugly hack was suggested [4], but it makes both INET and SMC code error-prone and hard to change. Also, yet another variant was fixed by a hacky commit 98d4435efcbf3 ("net/smc: prevent NULL pointer dereference in txopt_get"). Instead of papering over the root cause by such hacks, we should not allow non-INET socket to reuse the INET infra. Let's add inet_sock as the first member of smc_sock. [0]: kvfree_call_rcu(): Double-freed call. rcu_head 000000006921da73 WARNING: CPU: 0 PID: 6718 at mm/slab_common.c:1956 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 Modules linked in: CPU: 0 UID: 0 PID: 6718 Comm: syz.0.17 Tainted: G W 6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 lr : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 sp : ffff8000a03a7730 x29: ffff8000a03a7730 x28: 00000000fffffff5 x27: 1fffe000184823d3 x26: dfff800000000000 x25: ffff0000c2411e9e x24: ffff0000dd88da00 x23: ffff8000891ac9a0 x22: 00000000ffffffea x21: ffff8000891ac9a0 x20: ffff8000891ac9a0 x19: ffff80008afc2480 x18: 00000000ffffffff x17: 0000000000000000 x16: ffff80008ae642c8 x15: ffff700011ede14c x14: 1ffff00011ede14c x13: 0000000000000004 x12: ffffffffffffffff x11: ffff700011ede14c x10: 0000000000ff0100 x9 : 5fa3c1ffaf0ff000 x8 : 5fa3c1ffaf0ff000 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff8000a03a7078 x4 : ffff80008f766c20 x3 : ffff80008054d360 x2 : 0000000000000000 x1 : 0000000000000201 x0 : 0000000000000000 Call trace: kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 (P) cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914 netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000 smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581 smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912 security_inode_setsecurity+0x118/0x3c0 security/security.c:2706 __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251 __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295 vfs_setxattr+0x158/0x2ac fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] file_setxattr+0x1b8/0x294 fs/xattr.c:646 path_setxattrat+0x2ac/0x320 fs/xattr.c:711 __do_sys_fsetxattr fs/xattr.c:761 [inline] __se_sys_fsetxattr fs/xattr.c:758 [inline] __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758 __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151 el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600 [ ---truncated---
Severity ?
No CVSS data available.
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: d25a92ccae6bed02327b63d138e12e7806830f78 , < 5b02e397929e5b13b969ef1f8e43c7951e2864f5 (git)
Affected: d25a92ccae6bed02327b63d138e12e7806830f78 , < 67a167a6b8b45607bc34aa541d1c75097d18d460 (git)
Affected: d25a92ccae6bed02327b63d138e12e7806830f78 , < 60ada4fe644edaa6c2da97364184b0425e8aeaf5 (git)
Create a notification for this product.
    Linux Linux Affected: 6.11
Unaffected: 0 , < 6.11 (semver)
Unaffected: 6.12.40 , ≤ 6.12.* (semver)
Unaffected: 6.15.8 , ≤ 6.15.* (semver)
Unaffected: 6.16 , ≤ * (original_commit_for_fix)
Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/smc/af_smc.c",
            "net/smc/smc.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "5b02e397929e5b13b969ef1f8e43c7951e2864f5",
              "status": "affected",
              "version": "d25a92ccae6bed02327b63d138e12e7806830f78",
              "versionType": "git"
            },
            {
              "lessThan": "67a167a6b8b45607bc34aa541d1c75097d18d460",
              "status": "affected",
              "version": "d25a92ccae6bed02327b63d138e12e7806830f78",
              "versionType": "git"
            },
            {
              "lessThan": "60ada4fe644edaa6c2da97364184b0425e8aeaf5",
              "status": "affected",
              "version": "d25a92ccae6bed02327b63d138e12e7806830f78",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/smc/af_smc.c",
            "net/smc/smc.h"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.11"
            },
            {
              "lessThan": "6.11",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.15.*",
              "status": "unaffected",
              "version": "6.15.8",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.16",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.40",
                  "versionStartIncluding": "6.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.15.8",
                  "versionStartIncluding": "6.11",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.16",
                  "versionStartIncluding": "6.11",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nsmc: Fix various oops due to inet_sock type confusion.\n\nsyzbot reported weird splats [0][1] in cipso_v4_sock_setattr() while\nfreeing inet_sk(sk)-\u003einet_opt.\n\nThe address was freed multiple times even though it was read-only memory.\n\ncipso_v4_sock_setattr() did nothing wrong, and the root cause was type\nconfusion.\n\nThe cited commit made it possible to create smc_sock as an INET socket.\n\nThe issue is that struct smc_sock does not have struct inet_sock as the\nfirst member but hijacks AF_INET and AF_INET6 sk_family, which confuses\nvarious places.\n\nIn this case, inet_sock.inet_opt was actually smc_sock.clcsk_data_ready(),\nwhich is an address of a function in the text segment.\n\n  $ pahole -C inet_sock vmlinux\n  struct inet_sock {\n  ...\n          struct ip_options_rcu *    inet_opt;             /*   784     8 */\n\n  $ pahole -C smc_sock vmlinux\n  struct smc_sock {\n  ...\n          void                       (*clcsk_data_ready)(struct sock *); /*   784     8 */\n\nThe same issue for another field was reported before. [2][3]\n\nAt that time, an ugly hack was suggested [4], but it makes both INET\nand SMC code error-prone and hard to change.\n\nAlso, yet another variant was fixed by a hacky commit 98d4435efcbf3\n(\"net/smc: prevent NULL pointer dereference in txopt_get\").\n\nInstead of papering over the root cause by such hacks, we should not\nallow non-INET socket to reuse the INET infra.\n\nLet\u0027s add inet_sock as the first member of smc_sock.\n\n[0]:\nkvfree_call_rcu(): Double-freed call. rcu_head 000000006921da73\nWARNING: CPU: 0 PID: 6718 at mm/slab_common.c:1956 kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955\nModules linked in:\nCPU: 0 UID: 0 PID: 6718 Comm: syz.0.17 Tainted: G        W           6.16.0-rc4-syzkaller-g7482bb149b9f #0 PREEMPT\nTainted: [W]=WARN\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025\npstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)\npc : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955\nlr : kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955\nsp : ffff8000a03a7730\nx29: ffff8000a03a7730 x28: 00000000fffffff5 x27: 1fffe000184823d3\nx26: dfff800000000000 x25: ffff0000c2411e9e x24: ffff0000dd88da00\nx23: ffff8000891ac9a0 x22: 00000000ffffffea x21: ffff8000891ac9a0\nx20: ffff8000891ac9a0 x19: ffff80008afc2480 x18: 00000000ffffffff\nx17: 0000000000000000 x16: ffff80008ae642c8 x15: ffff700011ede14c\nx14: 1ffff00011ede14c x13: 0000000000000004 x12: ffffffffffffffff\nx11: ffff700011ede14c x10: 0000000000ff0100 x9 : 5fa3c1ffaf0ff000\nx8 : 5fa3c1ffaf0ff000 x7 : 0000000000000001 x6 : 0000000000000001\nx5 : ffff8000a03a7078 x4 : ffff80008f766c20 x3 : ffff80008054d360\nx2 : 0000000000000000 x1 : 0000000000000201 x0 : 0000000000000000\nCall trace:\n kvfree_call_rcu+0x94/0x3f0 mm/slab_common.c:1955 (P)\n cipso_v4_sock_setattr+0x2f0/0x3f4 net/ipv4/cipso_ipv4.c:1914\n netlbl_sock_setattr+0x240/0x334 net/netlabel/netlabel_kapi.c:1000\n smack_netlbl_add+0xa8/0x158 security/smack/smack_lsm.c:2581\n smack_inode_setsecurity+0x378/0x430 security/smack/smack_lsm.c:2912\n security_inode_setsecurity+0x118/0x3c0 security/security.c:2706\n __vfs_setxattr_noperm+0x174/0x5c4 fs/xattr.c:251\n __vfs_setxattr_locked+0x1ec/0x218 fs/xattr.c:295\n vfs_setxattr+0x158/0x2ac fs/xattr.c:321\n do_setxattr fs/xattr.c:636 [inline]\n file_setxattr+0x1b8/0x294 fs/xattr.c:646\n path_setxattrat+0x2ac/0x320 fs/xattr.c:711\n __do_sys_fsetxattr fs/xattr.c:761 [inline]\n __se_sys_fsetxattr fs/xattr.c:758 [inline]\n __arm64_sys_fsetxattr+0xc0/0xdc fs/xattr.c:758\n __invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]\n invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:49\n el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:132\n do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:151\n el0_svc+0x58/0x180 arch/arm64/kernel/entry-common.c:879\n el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:898\n el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:600\n\n[\n---truncated---"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-07-28T11:21:36.293Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/5b02e397929e5b13b969ef1f8e43c7951e2864f5"
        },
        {
          "url": "https://git.kernel.org/stable/c/67a167a6b8b45607bc34aa541d1c75097d18d460"
        },
        {
          "url": "https://git.kernel.org/stable/c/60ada4fe644edaa6c2da97364184b0425e8aeaf5"
        }
      ],
      "title": "smc: Fix various oops due to inet_sock type confusion.",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2025-38475",
    "datePublished": "2025-07-28T11:21:36.293Z",
    "dateReserved": "2025-04-16T04:51:24.021Z",
    "dateUpdated": "2025-07-28T11:21:36.293Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.




Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.