Linux Kernel up to 5.15.169/6.1.114/6.6.57/6.11.4 arm64 /adrp-self memcpy encoding error

Summaryinfo

A vulnerability categorized as problematic has been discovered in Linux Kernel up to 5.15.169/6.1.114/6.6.57/6.11.4. This affects the function memcpy of the file /adrp-self of the component arm64. Executing a manipulation can lead to encoding error. This vulnerability is tracked as CVE-2024-50194. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Linux Kernel up to 5.15.169/6.1.114/6.6.57/6.11.4 and classified as problematic. This vulnerability affects the function memcpy of the file /adrp-self of the component arm64. The manipulation with an unknown input leads to a encoding error vulnerability. The CWE definition for the vulnerability is CWE-172. The product does not properly encode or decode the data, resulting in unexpected values. The impact remains unknown. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: arm64: probes: Fix uprobes for big-endian kernels The arm64 uprobes code is broken for big-endian kernels as it doesn't convert the in-memory instruction encoding (which is always little-endian) into the kernel's native endianness before analyzing and simulating instructions. This may result in a few distinct problems: * The kernel may may erroneously reject probing an instruction which can safely be probed. * The kernel may erroneously erroneously permit stepping an instruction out-of-line when that instruction cannot be stepped out-of-line safely. * The kernel may erroneously simulate instruction incorrectly dur to interpretting the byte-swapped encoding. The endianness mismatch isn't caught by the compiler or sparse because: * The arch_uprobe::{insn,ixol} fields are encoded as arrays of u8, so the compiler and sparse have no idea these contain a little-endian 32-bit value. The core uprobes code populates these with a memcpy() which similarly does not handle endianness. * While the uprobe_opcode_t type is an alias for __le32, both arch_uprobe_analyze_insn() and arch_uprobe_skip_sstep() cast from u8[] to the similarly-named probe_opcode_t, which is an alias for u32. Hence there is no endianness conversion warning. Fix this by changing the arch_uprobe::{insn,ixol} fields to __le32 and adding the appropriate __le32_to_cpu() conversions prior to consuming the instruction encoding. The core uprobes copies these fields as opaque ranges of bytes, and so is unaffected by this change. At the same time, remove MAX_UINSN_BYTES and consistently use AARCH64_INSN_SIZE for clarity. Tested with the following: | #include | #include | | #define noinline __attribute__((noinline)) | | static noinline void *adrp_self(void) | { | void *addr; | | asm volatile( | " adrp %x0, adrp_self\n" | " add %x0, %x0, :lo12:adrp_self\n" | : "=r" (addr)); | } | | | int main(int argc, char *argv) | { | void *ptr = adrp_self(); | bool equal = (ptr == adrp_self); | | printf("adrp_self => %p\n" | "adrp_self() => %p\n" | "%s\n", | adrp_self, ptr, equal ? "EQUAL" : "NOT EQUAL"); | | return 0; | } .... where the adrp_self() function was compiled to: | 00000000004007e0 : | 4007e0: 90000000 adrp x0, 400000 | 4007e4: 911f8000 add x0, x0, #0x7e0 | 4007e8: d65f03c0 ret Before this patch, the ADRP is not recognized, and is assumed to be steppable, resulting in corruption of the result: | # ./adrp-self | adrp_self => 0x4007e0 | adrp_self() => 0x4007e0 | EQUAL | # echo 'p /root/adrp-self:0x007e0' > /sys/kernel/tracing/uprobe_events | # echo 1 > /sys/kernel/tracing/events/uprobes/enable | # ./adrp-self | adrp_self => 0x4007e0 | adrp_self() => 0xffffffffff7e0 | NOT EQUAL After this patch, the ADRP is correctly recognized and simulated: | # ./adrp-self | adrp_self => 0x4007e0 | adrp_self() => 0x4007e0 | EQUAL | # | # echo 'p /root/adrp-self:0x007e0' > /sys/kernel/tracing/uprobe_events | # echo 1 > /sys/kernel/tracing/events/uprobes/enable | # ./adrp-self | adrp_self => 0x4007e0 | adrp_self() => 0x4007e0 | EQUAL

The advisory is available at git.kernel.org. This vulnerability was named CVE-2024-50194 since 10/21/2024. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 212923 (CBL Mariner 2.0 Security Update: kernel (CVE-2024-50194)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.170, 6.1.115, 6.6.58 or 6.11.5 eliminates this vulnerability. Applying the patch cf60d19d4018/14841bb7a531/8165bf83b8a6/3d2530c65be0/13f8f1e05f1d is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (212923). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.169
• 6.1.114
• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.6.24
• 6.6.25
• 6.6.26
• 6.6.27
• 6.6.28
• 6.6.29
• 6.6.30
• 6.6.31
• 6.6.32
• 6.6.33
• 6.6.34
• 6.6.35
• 6.6.36
• 6.6.37
• 6.6.38
• 6.6.39
• 6.6.40
• 6.6.41
• 6.6.42
• 6.6.43
• 6.6.44
• 6.6.45
• 6.6.46
• 6.6.47
• 6.6.48
• 6.6.49
• 6.6.50
• 6.6.51
• 6.6.52
• 6.6.53
• 6.6.54
• 6.6.55
• 6.6.56
• 6.6.57
• 6.11.0
• 6.11.1
• 6.11.2
• 6.11.3
• 6.11.4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

• 🔍
• 🔍
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CVSSv4info

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CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

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Timelineinfo

Sourcesinfo

Entryinfo

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