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| author | Linus Torvalds <[email protected]> | 2025-07-30 16:58:50 +0000 |
|---|---|---|
| committer | Linus Torvalds <[email protected]> | 2025-07-30 16:58:50 +0000 |
| commit | d9104cec3e8fe4b458b74709853231385779001f (patch) | |
| tree | 1ffc3baa0e963d3301765a5d6cbd5410c8796ee4 /tools/testing/selftests/bpf/progs/verifier_map_in_map.c | |
| parent | Merge tag 'net-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ne... (diff) | |
| parent | Merge branch 'bpf-show-precise-rejected-function-when-attaching-to-__noreturn... (diff) | |
| download | kernel-d9104cec3e8fe4b458b74709853231385779001f.tar.gz kernel-d9104cec3e8fe4b458b74709853231385779001f.zip | |
Merge tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Pull bpf updates from Alexei Starovoitov:
- Remove usermode driver (UMD) framework (Thomas Weißschuh)
- Introduce Strongly Connected Component (SCC) in the verifier to
detect loops and refine register liveness (Eduard Zingerman)
- Allow 'void *' cast using bpf_rdonly_cast() and corresponding
'__arg_untrusted' for global function parameters (Eduard Zingerman)
- Improve precision for BPF_ADD and BPF_SUB operations in the verifier
(Harishankar Vishwanathan)
- Teach the verifier that constant pointer to a map cannot be NULL
(Ihor Solodrai)
- Introduce BPF streams for error reporting of various conditions
detected by BPF runtime (Kumar Kartikeya Dwivedi)
- Teach the verifier to insert runtime speculation barrier (lfence on
x86) to mitigate speculative execution instead of rejecting the
programs (Luis Gerhorst)
- Various improvements for 'veristat' (Mykyta Yatsenko)
- For CONFIG_DEBUG_KERNEL config warn on internal verifier errors to
improve bug detection by syzbot (Paul Chaignon)
- Support BPF private stack on arm64 (Puranjay Mohan)
- Introduce bpf_cgroup_read_xattr() kfunc to read xattr of cgroup's
node (Song Liu)
- Introduce kfuncs for read-only string opreations (Viktor Malik)
- Implement show_fdinfo() for bpf_links (Tao Chen)
- Reduce verifier's stack consumption (Yonghong Song)
- Implement mprog API for cgroup-bpf programs (Yonghong Song)
* tag 'bpf-next-6.17' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (192 commits)
selftests/bpf: Migrate fexit_noreturns case into tracing_failure test suite
selftests/bpf: Add selftest for attaching tracing programs to functions in deny list
bpf: Add log for attaching tracing programs to functions in deny list
bpf: Show precise rejected function when attaching fexit/fmod_ret to __noreturn functions
bpf: Fix various typos in verifier.c comments
bpf: Add third round of bounds deduction
selftests/bpf: Test invariants on JSLT crossing sign
selftests/bpf: Test cross-sign 64bits range refinement
selftests/bpf: Update reg_bound range refinement logic
bpf: Improve bounds when s64 crosses sign boundary
bpf: Simplify bounds refinement from s32
selftests/bpf: Enable private stack tests for arm64
bpf, arm64: JIT support for private stack
bpf: Move bpf_jit_get_prog_name() to core.c
bpf, arm64: Fix fp initialization for exception boundary
umd: Remove usermode driver framework
bpf/preload: Don't select USERMODE_DRIVER
selftests/bpf: Fix test dynptr/test_dynptr_memset_xdp_chunks failure
selftests/bpf: Fix test dynptr/test_dynptr_copy_xdp failure
selftests/bpf: Increase xdp data size for arm64 64K page size
...
Diffstat (limited to 'tools/testing/selftests/bpf/progs/verifier_map_in_map.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_map_in_map.c | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_map_in_map.c b/tools/testing/selftests/bpf/progs/verifier_map_in_map.c index 7d088ba99ea5..16b761e510f0 100644 --- a/tools/testing/selftests/bpf/progs/verifier_map_in_map.c +++ b/tools/testing/selftests/bpf/progs/verifier_map_in_map.c @@ -139,4 +139,122 @@ __naked void on_the_inner_map_pointer(void) : __clobber_all); } +SEC("socket") +__description("map_ptr is never null") +__success +__naked void map_ptr_is_never_null(void) +{ + asm volatile (" \ + r0 = 0; \ + r1 = %[map_in_map] ll; \ + if r1 != 0 goto l0_%=; \ + r10 = 42; \ +l0_%=: exit; \ +" : + : __imm(bpf_map_lookup_elem), + __imm_addr(map_in_map) + : __clobber_all); +} + +SEC("socket") +__description("map_ptr is never null inner") +__success +__naked void map_ptr_is_never_null_inner(void) +{ + asm volatile (" \ + r1 = 0; \ + *(u32*)(r10 - 4) = r1; \ + r2 = r10; \ + r2 += -4; \ + r1 = %[map_in_map] ll; \ + call %[bpf_map_lookup_elem]; \ + if r0 == 0 goto l0_%=; \ + if r0 != 0 goto l0_%=; \ + r10 = 42; \ +l0_%=: exit; \ +" : + : __imm(bpf_map_lookup_elem), + __imm_addr(map_in_map) + : __clobber_all); +} + +SEC("socket") +__description("map_ptr is never null inner spill fill") +__success +__naked void map_ptr_is_never_null_inner_spill_fill(void) +{ + asm volatile (" \ + r1 = 0; \ + *(u32*)(r10 - 4) = r1; \ + r2 = r10; \ + r2 += -4; \ + r1 = %[map_in_map] ll; \ + call %[bpf_map_lookup_elem]; \ + if r0 != 0 goto l0_%=; \ + exit; \ +l0_%=: *(u64 *)(r10 -16) = r0; \ + r1 = *(u64 *)(r10 -16); \ + if r1 == 0 goto l1_%=; \ + exit; \ +l1_%=: r10 = 42; \ + exit; \ +" : + : __imm(bpf_map_lookup_elem), + __imm_addr(map_in_map) + : __clobber_all); +} + +struct { + __uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS); + __uint(max_entries, 1); + __type(key, int); + __type(value, int); + __array(values, struct { + __uint(type, BPF_MAP_TYPE_RINGBUF); + __uint(max_entries, 64 * 1024); + }); +} rb_in_map SEC(".maps"); + +struct rb_ctx { + void *rb; + struct bpf_dynptr dptr; +}; + +static __always_inline struct rb_ctx __rb_event_reserve(__u32 sz) +{ + struct rb_ctx rb_ctx = {}; + void *rb; + __u32 cpu = bpf_get_smp_processor_id(); + __u32 rb_slot = cpu & 1; + + rb = bpf_map_lookup_elem(&rb_in_map, &rb_slot); + if (!rb) + return rb_ctx; + + rb_ctx.rb = rb; + bpf_ringbuf_reserve_dynptr(rb, sz, 0, &rb_ctx.dptr); + + return rb_ctx; +} + +static __noinline void __rb_event_submit(struct rb_ctx *ctx) +{ + if (!ctx->rb) + return; + + /* If the verifier (incorrectly) concludes that ctx->rb can be + * NULL at this point, we'll get "BPF_EXIT instruction in main + * prog would lead to reference leak" error + */ + bpf_ringbuf_submit_dynptr(&ctx->dptr, 0); +} + +SEC("socket") +int map_ptr_is_never_null_rb(void *ctx) +{ + struct rb_ctx event_ctx = __rb_event_reserve(256); + __rb_event_submit(&event_ctx); + return 0; +} + char _license[] SEC("license") = "GPL"; |
