GHSA-GXJ3-8G3M-8HPW

Vulnerability from github – Published: 2025-06-18 12:30 – Updated: 2025-11-14 18:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

x86/Kconfig: make CFI_AUTO_DEFAULT depend on !RUST or Rust >= 1.88

Calling core::fmt::write() from rust code while FineIBT is enabled results in a kernel panic:

[ 4614.199779] kernel BUG at arch/x86/kernel/cet.c:132! [ 4614.205343] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI [ 4614.211781] CPU: 2 UID: 0 PID: 6057 Comm: dmabuf_dump Tainted: G U O 6.12.17-android16-0-g6ab38c534a43 #1 9da040f27673ec3945e23b998a0f8bd64c846599 [ 4614.227832] Tainted: [U]=USER, [O]=OOT_MODULE [ 4614.241247] RIP: 0010:do_kernel_cp_fault+0xea/0xf0 ... [ 4614.398144] RIP: 0010:_RNvXs5_NtNtNtCs3o2tGsuHyou_4core3fmt3num3impyNtB9_7Display3fmt+0x0/0x20 [ 4614.407792] Code: 48 f7 df 48 0f 48 f9 48 89 f2 89 c6 5d e9 18 fd ff ff 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 41 81 ea 14 61 af 2c 74 03 0f 0b 90 <66> 0f 1f 00 55 48 89 e5 48 89 f2 48 8b 3f be 01 00 00 00 5d e9 e7 [ 4614.428775] RSP: 0018:ffffb95acfa4ba68 EFLAGS: 00010246 [ 4614.434609] RAX: 0000000000000000 RBX: 0000000000000010 RCX: 0000000000000000 [ 4614.442587] RDX: 0000000000000007 RSI: ffffb95acfa4ba70 RDI: ffffb95acfa4bc88 [ 4614.450557] RBP: ffffb95acfa4bae0 R08: ffff0a00ffffff05 R09: 0000000000000070 [ 4614.458527] R10: 0000000000000000 R11: ffffffffab67eaf0 R12: ffffb95acfa4bcc8 [ 4614.466493] R13: ffffffffac5d50f0 R14: 0000000000000000 R15: 0000000000000000 [ 4614.474473] ? __cfi__RNvXs5_NtNtNtCs3o2tGsuHyou_4core3fmt3num3impyNtB9_7Display3fmt+0x10/0x10 [ 4614.484118] ? _RNvNtCs3o2tGsuHyou_4core3fmt5write+0x1d2/0x250

This happens because core::fmt::write() calls core::fmt::rt::Argument::fmt(), which currently has CFI disabled:

library/core/src/fmt/rt.rs: 171 // FIXME: Transmuting formatter in new and indirectly branching to/calling 172 // it here is an explicit CFI violation. 173 #[allow(inline_no_sanitize)] 174 #[no_sanitize(cfi, kcfi)] 175 #[inline] 176 pub(super) unsafe fn fmt(&self, f: &mut Formatter<'_>) -> Result {

This causes a Control Protection exception, because FineIBT has sealed off the original function's endbr64.

This makes rust currently incompatible with FineIBT. Add a Kconfig dependency that prevents FineIBT from getting turned on by default if rust is enabled.

[ Rust 1.88.0 (scheduled for 2025-06-26) should have this fixed [1], and thus we relaxed the condition with Rust >= 1.88.

When objtool lands checking for this with e.g. [2], the plan is to ideally run that in upstream Rust's CI to prevent regressions early [3], since we do not control core's source code.

Alice tested the Rust PR backported to an older compiler.

Peter would like that Rust provides a stable core which can be pulled into the kernel: "Relying on that much out of tree code is 'unfortunate'".

- Miguel ]

[ Reduced splat. - Miguel ]

Show details on source website

{
  "affected": [],
  "aliases": [
    "CVE-2025-38033"
  ],
  "database_specific": {
    "cwe_ids": [],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-06-18T10:15:35Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nx86/Kconfig: make CFI_AUTO_DEFAULT depend on !RUST or Rust \u003e= 1.88\n\nCalling core::fmt::write() from rust code while FineIBT is enabled\nresults in a kernel panic:\n\n[ 4614.199779] kernel BUG at arch/x86/kernel/cet.c:132!\n[ 4614.205343] Oops: invalid opcode: 0000 [#1] PREEMPT SMP NOPTI\n[ 4614.211781] CPU: 2 UID: 0 PID: 6057 Comm: dmabuf_dump Tainted: G     U     O       6.12.17-android16-0-g6ab38c534a43 #1 9da040f27673ec3945e23b998a0f8bd64c846599\n[ 4614.227832] Tainted: [U]=USER, [O]=OOT_MODULE\n[ 4614.241247] RIP: 0010:do_kernel_cp_fault+0xea/0xf0\n...\n[ 4614.398144] RIP: 0010:_RNvXs5_NtNtNtCs3o2tGsuHyou_4core3fmt3num3impyNtB9_7Display3fmt+0x0/0x20\n[ 4614.407792] Code: 48 f7 df 48 0f 48 f9 48 89 f2 89 c6 5d e9 18 fd ff ff 0f 1f 84 00 00 00 00 00 f3 0f 1e fa 41 81 ea 14 61 af 2c 74 03 0f 0b 90 \u003c66\u003e 0f 1f 00 55 48 89 e5 48 89 f2 48 8b 3f be 01 00 00 00 5d e9 e7\n[ 4614.428775] RSP: 0018:ffffb95acfa4ba68 EFLAGS: 00010246\n[ 4614.434609] RAX: 0000000000000000 RBX: 0000000000000010 RCX: 0000000000000000\n[ 4614.442587] RDX: 0000000000000007 RSI: ffffb95acfa4ba70 RDI: ffffb95acfa4bc88\n[ 4614.450557] RBP: ffffb95acfa4bae0 R08: ffff0a00ffffff05 R09: 0000000000000070\n[ 4614.458527] R10: 0000000000000000 R11: ffffffffab67eaf0 R12: ffffb95acfa4bcc8\n[ 4614.466493] R13: ffffffffac5d50f0 R14: 0000000000000000 R15: 0000000000000000\n[ 4614.474473]  ? __cfi__RNvXs5_NtNtNtCs3o2tGsuHyou_4core3fmt3num3impyNtB9_7Display3fmt+0x10/0x10\n[ 4614.484118]  ? _RNvNtCs3o2tGsuHyou_4core3fmt5write+0x1d2/0x250\n\nThis happens because core::fmt::write() calls\ncore::fmt::rt::Argument::fmt(), which currently has CFI disabled:\n\nlibrary/core/src/fmt/rt.rs:\n171     // FIXME: Transmuting formatter in new and indirectly branching to/calling\n172     // it here is an explicit CFI violation.\n173     #[allow(inline_no_sanitize)]\n174     #[no_sanitize(cfi, kcfi)]\n175     #[inline]\n176     pub(super) unsafe fn fmt(\u0026self, f: \u0026mut Formatter\u003c\u0027_\u003e) -\u003e Result {\n\nThis causes a Control Protection exception, because FineIBT has sealed\noff the original function\u0027s endbr64.\n\nThis makes rust currently incompatible with FineIBT. Add a Kconfig\ndependency that prevents FineIBT from getting turned on by default\nif rust is enabled.\n\n[ Rust 1.88.0 (scheduled for 2025-06-26) should have this fixed [1],\n  and thus we relaxed the condition with Rust \u003e= 1.88.\n\n  When `objtool` lands checking for this with e.g. [2], the plan is\n  to ideally run that in upstream Rust\u0027s CI to prevent regressions\n  early [3], since we do not control `core`\u0027s source code.\n\n  Alice tested the Rust PR backported to an older compiler.\n\n  Peter would like that Rust provides a stable `core` which can be\n  pulled into the kernel: \"Relying on that much out of tree code is\n  \u0027unfortunate\u0027\".\n\n    - Miguel ]\n\n[ Reduced splat. - Miguel ]",
  "id": "GHSA-gxj3-8g3m-8hpw",
  "modified": "2025-11-14T18:31:21Z",
  "published": "2025-06-18T12:30:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-38033"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5595c31c370957aabe739ac3996aedba8267603f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5a8d073d87da4ad1496b35adaee5719e94665d81"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6b9956d09382bcbd5fd260c4b60ec48680a4cffb"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

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.

Loading…

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…