diff options
Diffstat (limited to 'tools/testing/selftests/bpf/progs/verifier_loops1.c')
| -rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_loops1.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_loops1.c b/tools/testing/selftests/bpf/progs/verifier_loops1.c index e07b43b78fd2..d248ce877f14 100644 --- a/tools/testing/selftests/bpf/progs/verifier_loops1.c +++ b/tools/testing/selftests/bpf/progs/verifier_loops1.c @@ -138,8 +138,7 @@ l0_%=: exit; \ SEC("tracepoint") __description("bounded recursion") __failure -/* verifier limitation in detecting max stack depth */ -__msg("the call stack of 8 frames is too deep !") +__msg("recursive call from") __naked void bounded_recursion(void) { asm volatile (" \ @@ -283,4 +282,25 @@ exit_%=: \ : __clobber_all); } +/* + * This test case triggered a bug in verifier.c:maybe_exit_scc(). + * Speculative execution path reaches stack access instruction, + * stops and triggers maybe_exit_scc() w/o accompanying maybe_enter_scc() call. + */ +SEC("socket") +__arch_x86_64 +__caps_unpriv(CAP_BPF) +__naked void maybe_exit_scc_bug1(void) +{ + asm volatile ( + "r0 = 100;" +"1:" + /* Speculative execution path reaches and stops here. */ + "*(u64 *)(r10 - 512) = r0;" + /* Condition is always false, but verifier speculatively executes the true branch. */ + "if r0 <= 0x0 goto 1b;" + "exit;" + ::: __clobber_all); +} + char _license[] SEC("license") = "GPL"; |