CVE-2021-47430
published 2024-05-21CVE-2021-47430: In the Linux kernel, the following vulnerability has been resolved: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n Commit 3c73b81a9164 ("x86/entry…
PriorityP410low3.3CVSS 3.1
AVLACLPRLUINSUCNINAL
EPSS
0.22%
12.3th percentile
In the Linux kernel, the following vulnerability has been resolved:
x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
Commit
3c73b81a9164 ("x86/entry, selftests: Further improve user entry sanity checks")
added a warning if AC is set when in the kernel.
Commit
662a0221893a3d ("x86/entry: Fix AC assertion")
changed the warning to only fire if the CPU supports SMAP.
However, the warning can still trigger on a machine that supports SMAP
but where it's disabled in the kernel config and when running the
syscall_nt selftest, for example:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 49 at irqentry_enter_from_user_mode
CPU: 0 PID: 49 Comm: init Tainted: G T 5.15.0-rc4+ #98 e6202628ee053b4f310759978284bd8bb0ce6905
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
RIP: 0010:irqentry_enter_from_user_mode
...
Call Trace:
? irqentry_enter
? exc_general_protection
? asm_exc_general_protection
? asm_exc_general_protectio
IS_ENABLED(CONFIG_X86_SMAP) could be added to the warning condition, but
even this would not be enough in case SMAP is disabled at boot time with
the "nosmap" parameter.
To be consistent with "nosmap" behaviour, clear X86_FEATURE_SMAP when
!CONFIG_X86_SMAP.
Found using entry-fuzz + satrandconfig.
[ bp: Massage commit message. ]
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 5.14.12-1 (bookworm) | linux 5.14.12-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 3c73b81a9164d0c1b6379d6672d2772a9e95168e < f2447f6587b8ffe42ba04d14ce67d429a1163e5e | f2447f6587b8ffe42ba04d14ce67d429a1163e5e |
| linux | linux | >= 3c73b81a9164d0c1b6379d6672d2772a9e95168e < 4e9ec1c65da98c293f75d83755dfa5e03075a6d0 | 4e9ec1c65da98c293f75d83755dfa5e03075a6d0 |
| linux | linux | >= 3c73b81a9164d0c1b6379d6672d2772a9e95168e < 3958b9c34c2729597e182cc606cc43942fd19f7c | 3958b9c34c2729597e182cc606cc43942fd19f7c |
| linux | linux_kernel | — | — |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.84-1 | 5.10.84-1 |
| linux | linux_kernel | >= 0 < 5.14.12-1 | 5.14.12-1 |
| linux | linux_kernel | >= 0 < 5.14.12-1 | 5.14.12-1 |
| linux | linux_kernel | >= 0 < 5.14.12-1 | 5.14.12-1 |
| linux | linux_kernel | >= 5.11 < 5.14.12 | 5.14.12 |
| linux | linux_kernel | >= 5.8.1 < 5.10.73 | 5.10.73 |
CVSS provenance
nvdv3.13.3LOWCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
osv3.3LOW
vendor_debian3.3LOW
vendor_redhat3.3LOW
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OSV
CVE-2021-47430: In the Linux kernel, the following vulnerability has been resolved: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n Commit 3c73b81a9164 ("x86
osv·2024-05-21·CVSS 3.3
CVE-2021-47430 [LOW] CVE-2021-47430: In the Linux kernel, the following vulnerability has been resolved: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n Commit 3c73b81a9164 ("x86
In the Linux kernel, the following vulnerability has been resolved: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n Commit 3c73b81a9164 ("x86/entry, selftests: Further improve user entry sanity checks") added a warning if AC is set when in the kernel. Commit 662a0221893a3d ("x86/entry: Fix AC assertion") changed the warning to only fire if the CPU supports SMAP. However, the warning can still trigger on a machine that supports SMAP but where it's disabled in the kernel config and when running the syscall_nt selftest, for example: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 49 at irqentry_enter_from_user_mode CPU: 0 PID: 49 Comm: init Tainted: G T 5.15.0-rc4+ #98 e6202628ee053b4f310759978284bd8bb0ce6905 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.
GHSA
GHSA-7wxc-v995-9mmf: In the Linux kernel, the following vulnerability has been resolved:
x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
Commit
3c73b81a9164 ("
ghsa_unreviewed·2024-05-21
CVE-2021-47430 [LOW] GHSA-7wxc-v995-9mmf: In the Linux kernel, the following vulnerability has been resolved:
x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
Commit
3c73b81a9164 ("
In the Linux kernel, the following vulnerability has been resolved:
x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
Commit
3c73b81a9164 ("x86/entry, selftests: Further improve user entry sanity checks")
added a warning if AC is set when in the kernel.
Commit
662a0221893a3d ("x86/entry: Fix AC assertion")
changed the warning to only fire if the CPU supports SMAP.
However, the warning can still trigger on a machine that supports SMAP
but where it's disabled in the kernel config and when running the
syscall_nt selftest, for example:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 49 at irqentry_enter_from_user_mode
CPU: 0 PID: 49 Comm: init Tainted: G T 5.15.0-rc4+ #98 e6202628ee053b4f310759978284bd8bb0ce6905
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), B
Red Hat
kernel: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
vendor_redhat·2024-05-21·CVSS 3.3
CVE-2021-47430 [LOW] kernel: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
kernel: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
In the Linux kernel, the following vulnerability has been resolved:
x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n
Commit
3c73b81a9164 ("x86/entry, selftests: Further improve user entry sanity checks")
added a warning if AC is set when in the kernel.
Commit
662a0221893a3d ("x86/entry: Fix AC assertion")
changed the warning to only fire if the CPU supports SMAP.
However, the warning can still trigger on a machine that supports SMAP
but where it's disabled in the kernel config and when running the
syscall_nt selftest, for example:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 49 at irqentry_enter_from_user_mode
CPU: 0 PID: 49 Comm: init Tainted: G T 5.15.0-rc4+ #98 e6202628ee053b4f310759978284bd8bb0ce6905
Debian
CVE-2021-47430: linux - In the Linux kernel, the following vulnerability has been resolved: x86/entry: ...
vendor_debian·2021·CVSS 3.3
CVE-2021-47430 [LOW] CVE-2021-47430: linux - In the Linux kernel, the following vulnerability has been resolved: x86/entry: ...
In the Linux kernel, the following vulnerability has been resolved: x86/entry: Clear X86_FEATURE_SMAP when CONFIG_X86_SMAP=n Commit 3c73b81a9164 ("x86/entry, selftests: Further improve user entry sanity checks") added a warning if AC is set when in the kernel. Commit 662a0221893a3d ("x86/entry: Fix AC assertion") changed the warning to only fire if the CPU supports SMAP. However, the warning can still trigger on a machine that supports SMAP but where it's disabled in the kernel config and when running the syscall_nt selftest, for example: ------------[ cut here ]------------ WARNING: CPU: 0 PID: 49 at irqentry_enter_from_user_mode CPU: 0 PID: 49 Comm: init Tainted: G T 5.15.0-rc4+ #98 e6202628ee053b4f310759978284bd8bb0ce6905 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/3958b9c34c2729597e182cc606cc43942fd19f7chttps://git.kernel.org/stable/c/4e9ec1c65da98c293f75d83755dfa5e03075a6d0https://git.kernel.org/stable/c/f2447f6587b8ffe42ba04d14ce67d429a1163e5ehttps://git.kernel.org/stable/c/3958b9c34c2729597e182cc606cc43942fd19f7chttps://git.kernel.org/stable/c/4e9ec1c65da98c293f75d83755dfa5e03075a6d0https://git.kernel.org/stable/c/f2447f6587b8ffe42ba04d14ce67d429a1163e5e
2024-05-21
Published