diff options
Diffstat (limited to 'arch/x86/net/bpf_jit_comp.c')
| -rw-r--r-- | arch/x86/net/bpf_jit_comp.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index a0d03503b3cb..d0c24b5a6abb 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -16,6 +16,7 @@ #include <asm/set_memory.h> #include <asm/nospec-branch.h> #include <asm/text-patching.h> +#include <asm/unwind.h> static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len) { @@ -2933,3 +2934,30 @@ void bpf_jit_free(struct bpf_prog *prog) bpf_prog_unlock_free(prog); } + +bool bpf_jit_supports_exceptions(void) +{ + /* We unwind through both kernel frames (starting from within bpf_throw + * call) and BPF frames. Therefore we require one of ORC or FP unwinder + * to be enabled to walk kernel frames and reach BPF frames in the stack + * trace. + */ + return IS_ENABLED(CONFIG_UNWINDER_ORC) || IS_ENABLED(CONFIG_UNWINDER_FRAME_POINTER); +} + +void arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie) +{ +#if defined(CONFIG_UNWINDER_ORC) || defined(CONFIG_UNWINDER_FRAME_POINTER) + struct unwind_state state; + unsigned long addr; + + for (unwind_start(&state, current, NULL, NULL); !unwind_done(&state); + unwind_next_frame(&state)) { + addr = unwind_get_return_address(&state); + if (!addr || !consume_fn(cookie, (u64)addr, (u64)state.sp, (u64)state.bp)) + break; + } + return; +#endif + WARN(1, "verification of programs using bpf_throw should have failed\n"); +} |