CVSS 3.1
Вероятност да бъде експлоатирана в следващите 30 дни (EPSS)
Атакува се
Време до експлоатация
Атакува се локално, без особени условия, с обикновен потребителски вход и без действие от потребителя.
Описание
Оригинално описание
In the Linux kernel, the following vulnerability has been resolved: bpf: Check load-acquire src ptr type before the load check_atomic_load() calls check_load_mem() before atomic_ptr_type_ok(). For a load-acquire that fetches into its own source register (dst_reg == src_reg), check_load_mem() overwrites src_reg's type with the type of the loaded value, so the subsequent atomic_ptr_type_ok() no longer sees the source pointer and fails to reject the disallowed types (ctx, pkt, flow_keys, sock). Since bpf_convert_ctx_accesses() does not rewrite atomic loads, the raw access to the underlying kernel object is left in place. The destination type is taken from the ctx access itself, so a load-acquire of the sk field of struct __sk_buff for example leaves the register typed as PTR_TO_SOCK_COMMON_OR_NULL, which type_is_sk_pointer() does not match either, while it actually holds unconverted struct sk_buff bytes. Once the NULL check has passed this is a type confusion, not just a leak of kernel data. Validate src_reg with check_reg_arg() and check the source pointer type with atomic_ptr_type_ok() before the load again, mirroring check_atomic_rmw(). Out-of-range register numbers are already rejected earlier by check_and_resolve_insns() (commit 503d21ef8eac ("bpf: Do register range validation early")), and the only exemption there, is_stack_arg_ldx(), requires BPF_LDX | BPF_MEM | BPF_DW and thus never matches a BPF_ATOMIC insn. atomic_ptr_type_ok() can therefore not dereference register state out of bounds, that is, the out-of-bounds read addressed by the Fixes commit below does not reappear (as proven also via selftest).
Засегнати продукти
- Linux Linux: c03bb2fa327e4c25d6c5360a8803a4b1cdc2d0b9 преди 6ee7b00888498cf387dd30729e18a05328b94709; c03bb2fa327e4c25d6c5360a8803a4b1cdc2d0b9 преди 422a416041172af1ac610736d5f556d22b31b115; c03bb2fa327e4c25d6c5360a8803a4b1cdc2d0b9 преди b87803391baa7e0bef60549d8841f12e549ad057
- Linux Linux: 6.15; преди 6.15; 6.18.52 до 6.18.*; 7.2.6 до 7.2.*; от 7.3 нататък
История
- 17 септември 2026 Публикувано
Други уязвимости в Linux Linux
Първоизточници
- https://www.cve.org/CVERecord?id=CVE-2026-90312
- https://nvd.nist.gov/vuln/detail/CVE-2026-90312
- https://git.kernel.org/stable/c/6ee7b00888498cf387dd30729e18a05328b94709
- https://git.kernel.org/stable/c/422a416041172af1ac610736d5f556d22b31b115
- https://git.kernel.org/stable/c/b87803391baa7e0bef60549d8841f12e549ad057