{"id":"CVE-2025-38033","state":"PUBLISHED","title":"x86/Kconfig: make CFI_AUTO_DEFAULT depend on !RUST or Rust >= 1.88","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/Kconfig: make CFI_AUTO_DEFAULT depend on !RUST or Rust >= 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 <66> 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(&self, f: &mut Formatter<'_>) -> Result {\n\nThis causes a Control Protection exception, because FineIBT has sealed\noff the original function's 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 >= 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's CI to prevent regressions\n  early [3], since we do not control `core`'s 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  'unfortunate'\".\n\n    - Miguel ]\n\n[ Reduced splat. - Miguel ]","publishedAt":"2025-06-18T09:33:20.195Z","updatedAt":"2026-05-11T21:19:58.573Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d6f635bcaca8d38dfa47ee20658705f9eff156b5","status":"affected","lessThan":"5a8d073d87da4ad1496b35adaee5719e94665d81","versionType":"git"},{"version":"d6f635bcaca8d38dfa47ee20658705f9eff156b5","status":"affected","lessThan":"6b9956d09382bcbd5fd260c4b60ec48680a4cffb","versionType":"git"},{"version":"d6f635bcaca8d38dfa47ee20658705f9eff156b5","status":"affected","lessThan":"5595c31c370957aabe739ac3996aedba8267603f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/Kconfig"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.31","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.14.9","status":"unaffected","lessThanOrEqual":"6.14.*","versionType":"semver"},{"version":"6.15","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/Kconfig"]}],"references":["https://git.kernel.org/stable/c/5a8d073d87da4ad1496b35adaee5719e94665d81","https://git.kernel.org/stable/c/6b9956d09382bcbd5fd260c4b60ec48680a4cffb","https://git.kernel.org/stable/c/5595c31c370957aabe739ac3996aedba8267603f"],"weaknesses":[],"ingestedAt":"2026-10-29T20:09:09.358Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2025/38xxx/CVE-2025-38033.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2025-38033","state":"PUBLISHED","datePublished":"2025-06-18T09:33:20.195Z","dateUpdated":"2026-05-11T21:19:58.573Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2025-04-16T04:51:23.978Z"},"containers":{"cna":{"title":"x86/Kconfig: make CFI_AUTO_DEFAULT depend on !RUST or Rust >= 1.88","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nx86/Kconfig: make CFI_AUTO_DEFAULT depend on !RUST or Rust >= 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 <66> 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(&self, f: &mut Formatter<'_>) -> Result {\n\nThis causes a Control Protection exception, because FineIBT has sealed\noff the original function's 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 >= 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's CI to prevent regressions\n  early [3], since we do not control `core`'s 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  'unfortunate'\".\n\n    - Miguel ]\n\n[ Reduced splat. - Miguel ]"}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"d6f635bcaca8d38dfa47ee20658705f9eff156b5","status":"affected","lessThan":"5a8d073d87da4ad1496b35adaee5719e94665d81","versionType":"git"},{"version":"d6f635bcaca8d38dfa47ee20658705f9eff156b5","status":"affected","lessThan":"6b9956d09382bcbd5fd260c4b60ec48680a4cffb","versionType":"git"},{"version":"d6f635bcaca8d38dfa47ee20658705f9eff156b5","status":"affected","lessThan":"5595c31c370957aabe739ac3996aedba8267603f","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/Kconfig"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"6.11","status":"affected"},{"version":"0","status":"unaffected","lessThan":"6.11","versionType":"semver"},{"version":"6.12.31","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.14.9","status":"unaffected","lessThanOrEqual":"6.14.*","versionType":"semver"},{"version":"6.15","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["arch/x86/Kconfig"]}],"references":[{"url":"https://git.kernel.org/stable/c/5a8d073d87da4ad1496b35adaee5719e94665d81"},{"url":"https://git.kernel.org/stable/c/6b9956d09382bcbd5fd260c4b60ec48680a4cffb"},{"url":"https://git.kernel.org/stable/c/5595c31c370957aabe739ac3996aedba8267603f"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T21:19:58.573Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.12.31"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.14.9"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.15"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}