[compiler-rt] 64529eb - [DFSan] Increase size of buffer to fix possibly-flakey test.

[Andrew Browne via llvm-commits]

Author: Andrew Browne
Date: 2022-09-02T17:52:12-07:00
New Revision: 64529eb2917cc48fe0449df2110908a909ad055f

URL: https://github.com/llvm/llvm-project/commit/64529eb2917cc48fe0449df2110908a909ad055f
DIFF: https://github.com/llvm/llvm-project/commit/64529eb2917cc48fe0449df2110908a909ad055f.diff

LOG: [DFSan] Increase size of buffer to fix possibly-flakey test.

Observed a test failure where "Returned length: 3054".

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D133227

Added: 
    

Modified: 
    compiler-rt/test/dfsan/origin_stack_trace.c

Removed: 
    


################################################################################
diff  --git a/compiler-rt/test/dfsan/origin_stack_trace.c b/compiler-rt/test/dfsan/origin_stack_trace.c
index dbc6fc8e513b7..c8b964bf98d49 100644
--- a/compiler-rt/test/dfsan/origin_stack_trace.c
+++ b/compiler-rt/test/dfsan/origin_stack_trace.c
@@ -8,6 +8,8 @@
 //
 // REQUIRES: x86_64-target-arch
 
+#include <assert.h>
+#include <malloc.h>
 #include <sanitizer/dfsan_interface.h>
 #include <stdio.h>
 #include <string.h>
@@ -24,9 +26,7 @@ NOINLINE void bar(int depth, void *addr, int size) {
   }
 }
 
-NOINLINE void baz(int depth, void *addr, int size) {
-  bar(depth, addr, size);
-}
+NOINLINE void baz(int depth, void *addr, int size) { bar(depth, addr, size); }
 
 int main(int argc, char *argv[]) {
   int a = 10;
@@ -39,27 +39,33 @@ int main(int argc, char *argv[]) {
   // CHECK: #0 {{.*}} in main {{.*}}origin_stack_trace.c:[[@LINE-4]]
 
   // CHECK: Origin value: {{.*}}, Taint value was created at
-  // CHECK: #0 {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-19]]
-  // CHECK-COUNT-8: #{{[0-9]+}} {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-22]]
-  // CHECK: #9 {{.*}} in baz.dfsan {{.*}}origin_stack_trace.c:[[@LINE-16]]
-
-  char buf[3000];
-  size_t length = dfsan_sprint_origin_trace(&c, NULL, buf, sizeof(buf));
+  // CHECK: #0 {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-17]]
+  // CHECK-COUNT-8: #{{[0-9]+}} {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-20]]
+  // CHECK: #9 {{.*}} in baz.dfsan {{.*}}origin_stack_trace.c:[[@LINE-15]]
+
+  // Test logic expects this buffer to be large enough.
+  // String contains current paths, which could vary in length.
+  // Make this buffer much larger than necessary to accomodate variation.
+  const size_t kBufSize = 8192;
+  char *buf = (char *)malloc(kBufSize);
+  size_t length = dfsan_sprint_origin_trace(&c, NULL, buf, kBufSize);
+  assert(kBufSize > length);
 
   printf("==OUTPUT==\n\n%s==EOS==\n", buf);
   // CHECK: ==OUTPUT==
   // CHECK: Taint value 0x1 {{.*}} origin tracking ()
   // CHECK: Origin value: {{.*}}, Taint value was stored to memory at
-  // CHECK: #0 {{.*}} in main {{.*}}origin_stack_trace.c:[[@LINE-18]]
+  // CHECK: #0 {{.*}} in main {{.*}}origin_stack_trace.c:[[@LINE-23]]
 
   // CHECK: Origin value: {{.*}}, Taint value was created at
-  // CHECK: #0 {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-33]]
-  // CHECK-COUNT-8: #{{[0-9]+}} {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-36]]
-  // CHECK: #9 {{.*}} in baz.dfsan {{.*}}origin_stack_trace.c:[[@LINE-30]]
+  // CHECK: #0 {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-36]]
+  // CHECK-COUNT-8: #{{[0-9]+}} {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-39]]
+  // CHECK: #9 {{.*}} in baz.dfsan {{.*}}origin_stack_trace.c:[[@LINE-34]]
   // CHECK: ==EOS==
 
   char tinybuf[18];
-  size_t same_length = dfsan_sprint_origin_trace(&c, NULL, tinybuf, sizeof(tinybuf));
+  size_t same_length =
+      dfsan_sprint_origin_trace(&c, NULL, tinybuf, sizeof(tinybuf));
 
   printf("==TRUNCATED OUTPUT==\n\n%s==EOS==\n", tinybuf);
   // CHECK: ==TRUNCATED OUTPUT==
@@ -73,18 +79,20 @@ int main(int argc, char *argv[]) {
   // CHECK: Actual length: [[#LEN]]
   // CHECK: Returned length with truncation: [[#LEN]]
 
-  size_t length_with_desc = dfsan_sprint_origin_trace(&c, "DESCRIPTION", buf, sizeof(buf));
+  size_t length_with_desc =
+      dfsan_sprint_origin_trace(&c, "DESCRIPTION", buf, kBufSize);
+  assert(kBufSize > length_with_desc);
 
   printf("==OUTPUT==\n\n%s==EOS==\n", buf);
   // CHECK: ==OUTPUT==
   // CHECK: Taint value 0x1 {{.*}} origin tracking (DESCRIPTION)
   // CHECK: Origin value: {{.*}}, Taint value was stored to memory at
-  // CHECK: #0 {{.*}} in main {{.*}}origin_stack_trace.c:[[@LINE-47]]
+  // CHECK: #0 {{.*}} in main {{.*}}origin_stack_trace.c:[[@LINE-55]]
 
   // CHECK: Origin value: {{.*}}, Taint value was created at
-  // CHECK: #0 {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-62]]
-  // CHECK-COUNT-8: #{{[0-9]+}} {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-65]]
-  // CHECK: #9 {{.*}} in baz.dfsan {{.*}}origin_stack_trace.c:[[@LINE-59]]
+  // CHECK: #0 {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-68]]
+  // CHECK-COUNT-8: #{{[0-9]+}} {{.*}} in bar.dfsan {{.*}}origin_stack_trace.c:[[@LINE-71]]
+  // CHECK: #9 {{.*}} in baz.dfsan {{.*}}origin_stack_trace.c:[[@LINE-66]]
   // CHECK: ==EOS==
 
   printf("Returned length: %zu\n", length_with_desc);
@@ -97,4 +105,6 @@ int main(int argc, char *argv[]) {
   printf("Returned length: %zu\n", length);
   // CHECK: Output=""
   // CHECK: Returned length: [[#LEN]]
+
+  free(buf);
 }