// For flags

CVE-2024-53125

bpf: sync_linked_regs() must preserve subreg_def

Severity Score

5.0
*CVSS v2

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved: bpf: sync_linked_regs() must preserve subreg_def Range propagation must not affect subreg_def marks, otherwise the
following example is rewritten by verifier incorrectly when
BPF_F_TEST_RND_HI32 flag is set: 0: call bpf_ktime_get_ns call bpf_ktime_get_ns 1: r0 &= 0x7fffffff after verifier r0 &= 0x7fffffff 2: w1 = w0 rewrites w1 = w0 3: if w0 < 10 goto +0 --------------> r11 = 0x2f5674a6 (r) 4: r1 >>= 32 r11 <<= 32 (r) 5: r0 = r1 r1 |= r11 (r) 6: exit; if w0 < 0xa goto pc+0 r1 >>= 32 r0 = r1 exit (or zero extension of w1 at (2) is missing for architectures that require zero extension for upper register half). The following happens w/o this patch:
- r0 is marked as not a subreg at (0);
- w1 is marked as subreg at (2);
- w1 subreg_def is overridden at (3) by copy_register_state();
- w1 is read at (5) but mark_insn_zext() does not mark (2) for zero extension, because w1 subreg_def is not set;
- because of BPF_F_TEST_RND_HI32 flag verifier inserts random value for hi32 bits of (2) (marked (r));
- this random value is read at (5).

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: bpf: sync_linked_regs() debe preservar subreg_def La propagación del rango no debe afectar a las marcas subreg_def, de lo contrario el siguiente ejemplo es reescrito incorrectamente por el verificador cuando el indicador BPF_F_TEST_RND_HI32 está establecido: 0: llamar a bpf_ktime_get_ns llamar a bpf_ktime_get_ns 1: r0 &amp;= 0x7fffffff después del verificador r0 &amp;= 0x7fffffff 2: w1 = w0 reescribe w1 = w0 3: si w0 &lt; 10 goto +0 --------------&gt; r11 = 0x2f5674a6 (r) 4: r1 &gt;&gt;= 32 r11 &lt;&lt;= 32 (r) 5: r0 = r1 r1 |= r11 (r) 6: salir; si w0 &lt; 0xa goto pc+0 r1 &gt;&gt;= 32 r0 = r1 salir (o falta la extensión cero de w1 en (2) para arquitecturas que requieren extensión cero para la mitad superior del registro). Lo siguiente ocurre sin este parche: - r0 está marcado como no un subreg en (0); - w1 está marcado como subreg en (2); - el subreg_def de w1 es anulado en (3) por copy_register_state(); - w1 se lee en (5) pero mark_insn_zext() no marca (2) para extensión cero, porque el subreg_def de w1 no está configurado; - debido al indicador BPF_F_TEST_RND_HI32, el verificador inserta un valor aleatorio para los bits hi32 de (2) (marcado (r)); - este valor aleatorio se lee en (5).

In the Linux kernel, the following vulnerability has been resolved: bpf: sync_linked_regs() must preserve subreg_def Range propagation must not affect subreg_def marks, otherwise the following example is rewritten by verifier incorrectly when BPF_F_TEST_RND_HI32 flag is set: 0: call bpf_ktime_get_ns call bpf_ktime_get_ns 1: r0 &= 0x7fffffff after verifier r0 &= 0x7fffffff 2: w1 = w0 rewrites w1 = w0 3: if w0 < 10 goto +0 --------------> r11 = 0x2f5674a6 (r) 4: r1 >>= 32 r11 <<= 32 (r) 5: r0 = r1 r1 |= r11 (r) 6: exit; if w0 < 0xa goto pc+0 r1 >>= 32 r0 = r1 exit (or zero extension of w1 at (2) is missing for architectures that require zero extension for upper register half). The following happens w/o this patch: - r0 is marked as not a subreg at (0); - w1 is marked as subreg at (2); - w1 subreg_def is overridden at (3) by copy_register_state(); - w1 is read at (5) but mark_insn_zext() does not mark (2) for zero extension, because w1 subreg_def is not set; - because of BPF_F_TEST_RND_HI32 flag verifier inserts random value for hi32 bits of (2) (marked (r)); - this random value is read at (5).

Attila Szász discovered that the HFS+ file system implementation in the Linux Kernel contained a heap overflow vulnerability. An attacker could use a specially crafted file system image that, when mounted, could cause a denial of service or possibly execute arbitrary code. Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Authentication
None
Confidentiality
Partial
Integrity
None
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2024-11-19 CVE Reserved
  • 2024-12-04 CVE Published
  • 2024-12-19 CVE Updated
  • 2025-03-29 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 5.10.232
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 5.10.232"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 5.15.175
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 5.15.175"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 6.1.121
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 6.1.121"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 6.6.67
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 6.6.67"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 6.11.6
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 6.11.6"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.10 < 6.12
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.10 < 6.12"
en
Affected