Linux Kernel up to 6.10.4 bpf check_func_arg_reg_off out-of-bounds

Summaryinfo

A vulnerability classified as problematic was found in Linux Kernel up to 6.10.4. Impacted is the function check_func_arg_reg_off of the component bpf. Such manipulation leads to out-of-bounds. This vulnerability is documented as CVE-2024-43910. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.10.4. It has been rated as problematic. Affected by this issue is the function check_func_arg_reg_off of the component bpf. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: bpf: add missing check_func_arg_reg_off() to prevent out-of-bounds memory accesses Currently, it's possible to pass in a modified CONST_PTR_TO_DYNPTR to a global function as an argument. The adverse effects of this is that BPF helpers can continue to make use of this modified CONST_PTR_TO_DYNPTR from within the context of the global function, which can unintentionally result in out-of-bounds memory accesses and therefore compromise overall system stability i.e. [ 244.157771] BUG: KASAN: slab-out-of-bounds in bpf_dynptr_data+0x137/0x140 [ 244.161345] Read of size 8 at addr ffff88810914be68 by task test_progs/302 [ 244.167151] CPU: 0 PID: 302 Comm: test_progs Tainted: G O E 6.10.0-rc3-00131-g66b586715063 #533 [ 244.174318] Call Trace: [ 244.175787] [ 244.177356] dump_stack_lvl+0x66/0xa0 [ 244.179531] print_report+0xce/0x670 [ 244.182314] ? __virt_addr_valid+0x200/0x3e0 [ 244.184908] kasan_report+0xd7/0x110 [ 244.187408] ? bpf_dynptr_data+0x137/0x140 [ 244.189714] ? bpf_dynptr_data+0x137/0x140 [ 244.192020] bpf_dynptr_data+0x137/0x140 [ 244.194264] bpf_prog_b02a02fdd2bdc5fa_global_call_bpf_dynptr_data+0x22/0x26 [ 244.198044] bpf_prog_b0fe7b9d7dc3abde_callback_adjust_bpf_dynptr_reg_off+0x1f/0x23 [ 244.202136] bpf_user_ringbuf_drain+0x2c7/0x570 [ 244.204744] ? 0xffffffffc0009e58 [ 244.206593] ? __pfx_bpf_user_ringbuf_drain+0x10/0x10 [ 244.209795] bpf_prog_33ab33f6a804ba2d_user_ringbuf_callback_const_ptr_to_dynptr_reg_off+0x47/0x4b [ 244.215922] bpf_trampoline_6442502480+0x43/0xe3 [ 244.218691] __x64_sys_prlimit64+0x9/0xf0 [ 244.220912] do_syscall_64+0xc1/0x1d0 [ 244.223043] entry_SYSCALL_64_after_hwframe+0x77/0x7f [ 244.226458] RIP: 0033:0x7ffa3eb8f059 [ 244.228582] Code: 08 89 e8 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 3d 01 f0 ff ff 73 01 c3 48 8b 0d 8f 1d 0d 00 f7 d8 64 89 01 48 [ 244.241307] RSP: 002b:00007ffa3e9c6eb8 EFLAGS: 00000206 ORIG_RAX: 000000000000012e [ 244.246474] RAX: ffffffffffffffda RBX: 00007ffa3e9c7cdc RCX: 00007ffa3eb8f059 [ 244.250478] RDX: 00007ffa3eb162b4 RSI: 0000000000000000 RDI: 00007ffa3e9c7fb0 [ 244.255396] RBP: 00007ffa3e9c6ed0 R08: 00007ffa3e9c76c0 R09: 0000000000000000 [ 244.260195] R10: 0000000000000000 R11: 0000000000000206 R12: ffffffffffffff80 [ 244.264201] R13: 000000000000001c R14: 00007ffc5d6b4260 R15: 00007ffa3e1c7000 [ 244.268303] Add a check_func_arg_reg_off() to the path in which the BPF verifier verifies the arguments of global function arguments, specifically those which take an argument of type ARG_PTR_TO_DYNPTR | MEM_RDONLY. Also, process_dynptr_func() doesn't appear to perform any explicit and strict type matching on the supplied register type, so let's also enforce that a register either type PTR_TO_STACK or CONST_PTR_TO_DYNPTR is by the caller.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2024-43910 since 08/17/2024. The exploitation is known to be difficult. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 212724 (Ubuntu 22.04 LTS / 24.04 LTS : Linux kernel vulnerabilities (USN-7154-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.10.5 eliminates this vulnerability. Applying the patch 13663a7c644b/ec2b9a5e11e5 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 (212724). 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

• 6.10.0
• 6.10.1
• 6.10.2
• 6.10.3
• 6.10.4

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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