1// Tests use-after-return detection and reporting.
2// RUN: %clang_hwasan -O0 -g %s -o %t && not %run %t 2>&1 | FileCheck %s
3// RUN: %clang_hwasan -O3 -g %s -o %t && not %run %t 2>&1 | FileCheck %s
4// RUN: %clang_hwasan -g %s -o %t && not %env_hwasan_opts=symbolize=0 %run %t 2>&1 | FileCheck %s --check-prefix=NOSYM
5
6// Run the same test as above, but using the __hwasan_add_frame_record libcall.
7// The output should be the exact same.
8// RUN: %clang_hwasan -g %s -o %t -mllvm -hwasan-record-stack-history=libcall && not %env_hwasan_opts=symbolize=0 %run %t 2>&1 | FileCheck %s --check-prefix=NOSYM
9
10// Stack histories currently are not recorded on x86.
11// XFAIL: target=x86_64{{.*}}
12
13#include <assert.h>
14#include <sanitizer/hwasan_interface.h>
15
16void USE(void *x) { // pretend_to_do_something(void *x)
17 __asm__ __volatile__("" : : "r" (x) : "memory");
18}
19
20__attribute__((noinline))
21char *buggy() {
22 char zzz[0x800];
23 char yyy[0x800];
24 // Tags for stack-allocated variables can occasionally be zero, resulting in
25 // a false negative for this test. The tag allocation algorithm is not easy
26 // to fix, hence we work around it: if the tag is zero, we use the
27 // neighboring variable instead, which must have a different (hence non-zero)
28 // tag.
29 char *volatile p;
30 if (__hwasan_tag_pointer(p: zzz, tag: 0) == zzz) {
31 assert(__hwasan_tag_pointer(yyy, 0) != yyy);
32 p = yyy;
33 } else {
34 p = zzz;
35 }
36 return p;
37}
38
39__attribute__((noinline)) void Unrelated1() { int A[2]; USE(x: &A[0]); }
40__attribute__((noinline)) void Unrelated2() { int BB[3]; USE(x: &BB[0]); }
41__attribute__((noinline)) void Unrelated3() { int CCC[4]; USE(x: &CCC[0]); }
42
43int main() {
44 char *p = buggy();
45 Unrelated1();
46 Unrelated2();
47 Unrelated3();
48 return *p;
49 // CHECK: READ of size 1 at
50 // CHECK: #0 {{.*}} in main{{.*}}stack-uar.c:[[@LINE-2]]
51 // CHECK: Cause: stack tag-mismatch
52 // CHECK: is located in stack of thread
53 // CHECK: Potentially referenced stack objects:
54 // CHECK: Cause: use-after-scope
55 // CHECK-NEXT: 0x{{.*}} is located 0 bytes inside a 2048-byte local variable {{zzz|yyy}} [0x{{.*}},0x{{.*}}) in buggy {{.*}}stack-uar.c:
56 // CHECK: Memory tags around the buggy address
57
58 // NOSYM: Previously allocated frames:
59 // NOSYM-NEXT: record_addr:0x{{.*}} record:0x{{.*}} ({{.*}}/stack-uar.c.tmp+0x{{.*}}){{$}}
60 // NOSYM-NEXT: record_addr:0x{{.*}} record:0x{{.*}} ({{.*}}/stack-uar.c.tmp+0x{{.*}}){{$}}
61 // NOSYM-NEXT: record_addr:0x{{.*}} record:0x{{.*}} ({{.*}}/stack-uar.c.tmp+0x{{.*}}){{$}}
62 // NOSYM-NEXT: record_addr:0x{{.*}} record:0x{{.*}} ({{.*}}/stack-uar.c.tmp+0x{{.*}}){{$}}
63 // NOSYM: Memory tags around the buggy address
64
65 // CHECK: SUMMARY: HWAddressSanitizer: tag-mismatch {{.*}} in main
66}
67

source code of compiler-rt/test/hwasan/TestCases/stack-uar.c