CVE-2026-53346
UnknownSummary
A bug in the Rust compiler causes the -Cforce-unwind-tables=y flag to emit uwtable annotation only for functions, not for the module. This leads to incorrect DWARF information for KASAN constructors, causing boot failures when CONFIG_UNWIND_PATCH_PAC_INTO_SCS is enabled.
Risk Assessment
The organization may experience system crashes during boot due to incorrect PAC instruction patching, preventing kernel startup and potentially causing service disruptions.
Recommendation
It is recommended to update the Linux kernel to a version containing the fix that adds the uwtable LLVM module flag for ARM64, and ensure the rustc version is 1.98.0 or later.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: rust: arm64: set uwtable llvm module flag for CONFIG_UNWIND_TABLES Due to a rustc bug [1] the -Cforce-unwind-tables=y flag only emits the uwtable annotation for functions, but not for the module. This means that compiler-generated functions such as 'asan.module_ctor' do not receive the uwtable annotation. When CONFIG_UNWIND_PATCH_PAC_INTO_SCS is enabled, this leads to boot failures because the dwarf information emitted for the kasan constructors is wrong, which causes the SCS boot patching code to patch the constructor in an illegal manner. Specifically, the paciasp instruction is patched, but the autiasp instruction is not. This mismatch leads to a crash when the constructor is called during boot. ================================================================== BUG: KASAN: global-out-of-bounds in do_basic_setup+0x4c/0x90 Read of size 8 at addr ffffffe3cc7eb488 by task swapper/0/1 Specifically the faulting instruction is the (*fn)() to invoke the constructor in do_ctors() of the init/main.c file. Once the fix lands in rustc, this flag can be made conditional on the rustc version. Note that passing the flag on a rustc with the fix present has no effect. [ The fix [1] has landed for Rust 1.98.0 (expected release on 2026-08-20). Thus add a version check as discussed. - Miguel ] [ Adjusted link and comment. - Miguel ]