[msan] Intercept shmat.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@193581 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 105 insertions, 5 deletions

diff --git a/lib/msan/msan_interceptors.cc b/lib/msan/msan_interceptors.cc
index 842270dc..0c42e047 100644
--- a/lib/msan/msan_interceptors.cc
+++ b/lib/msan/msan_interceptors.cc
@@ -1157,6 +1157,22 @@ INTERCEPTOR(int, __cxa_atexit, void (*func)(void *), void *arg,
   return REAL(__cxa_atexit)(MSanAtExitWrapper, r, dso_handle);
 }
 
+DECLARE_REAL(int, shmctl, int shmid, int cmd, void *buf)
+
+INTERCEPTOR(void *, shmat, int shmid, const void *shmaddr, int shmflg) {
+  ENSURE_MSAN_INITED();
+  void *p = REAL(shmat)(shmid, shmaddr, shmflg);
+  if (p != (void *)-1) {
+    __sanitizer_shmid_ds ds;
+    int res = REAL(shmctl)(shmid, shmctl_ipc_stat, &ds);
+    if (!res) {
+      __msan_unpoison(p, ds.shm_segsz);
+    }
+  }
+  return p;
+}
+
+
 struct MSanInterceptorContext {
   bool in_interceptor_scope;
 };
@@ -1459,6 +1475,7 @@ void InitializeInterceptors() {
   INTERCEPT_FUNCTION(pthread_join);
   INTERCEPT_FUNCTION(tzset);
   INTERCEPT_FUNCTION(__cxa_atexit);
+  INTERCEPT_FUNCTION(shmat);
 
   if (REAL(pthread_key_create)(&g_thread_finalize_key, &thread_finalize)) {
     Printf("MemorySanitizer: failed to create thread key\n");
diff --git a/lib/msan/tests/msan_test.cc b/lib/msan/tests/msan_test.cc
index e6923828..dd9669be 100644
--- a/lib/msan/tests/msan_test.cc
+++ b/lib/msan/tests/msan_test.cc
@@ -1146,6 +1146,34 @@ TEST(MemorySanitizer, shmctl) {
   ASSERT_GT(res, -1);
 }
 
+TEST(MemorySanitizer, shmat) {
+  void *p = mmap(NULL, 4096, PROT_READ | PROT_WRITE,
+                 MAP_PRIVATE | MAP_ANONYMOUS, 0, 0);
+  ASSERT_NE(MAP_FAILED, p);
+
+  ((char *)p)[10] = *GetPoisoned<U1>();
+  ((char *)p)[4095] = *GetPoisoned<U1>();
+
+  int res = munmap(p, 4096);
+  ASSERT_EQ(0, res);
+
+  int id = shmget(IPC_PRIVATE, 4096, 0644 | IPC_CREAT);
+  ASSERT_GT(id, -1);
+
+  void *q = shmat(id, p, 0);
+  ASSERT_EQ(p, q);
+
+  EXPECT_NOT_POISONED(((char *)q)[0]);
+  EXPECT_NOT_POISONED(((char *)q)[10]);
+  EXPECT_NOT_POISONED(((char *)q)[4095]);
+
+  res = shmdt(q);
+  ASSERT_EQ(0, res);
+
+  res = shmctl(id, IPC_RMID, 0);
+  ASSERT_GT(res, -1);
+}
+
 TEST(MemorySanitizer, random_r) {
   int32_t x;
   char z[64];
diff --git a/lib/sanitizer_common/sanitizer_common_interceptors.inc b/lib/sanitizer_common/sanitizer_common_interceptors.inc
index e13df5c2..f5179e24 100644
--- a/lib/sanitizer_common/sanitizer_common_interceptors.inc
+++ b/lib/sanitizer_common/sanitizer_common_interceptors.inc
@@ -2512,7 +2512,7 @@ INTERCEPTOR(int, shmctl, int shmid, int cmd, void *buf) {
   if (res >= 0) {
     unsigned sz = 0;
     if (cmd == shmctl_ipc_stat || cmd == shmctl_shm_stat)
-      sz = struct_shmid_ds_sz;
+      sz = sizeof(__sanitizer_shmid_ds);
     else if (cmd == shmctl_ipc_info)
       sz = struct_shminfo_sz;
     else if (cmd == shmctl_shm_info)
diff --git a/lib/sanitizer_common/sanitizer_common_syscalls.inc b/lib/sanitizer_common/sanitizer_common_syscalls.inc
index 942ffc4c..0f500d63 100644
--- a/lib/sanitizer_common/sanitizer_common_syscalls.inc
+++ b/lib/sanitizer_common/sanitizer_common_syscalls.inc
@@ -2067,7 +2067,7 @@ PRE_SYSCALL(shmctl)(long shmid, long cmd, void *buf) {}
 
 POST_SYSCALL(shmctl)(long res, long shmid, long cmd, void *buf) {
   if (res >= 0) {
-    if (buf) POST_WRITE(buf, struct_shmid_ds_sz);
+    if (buf) POST_WRITE(buf, sizeof(__sanitizer_shmid_ds));
   }
 }
 
diff --git a/lib/sanitizer_common/sanitizer_platform_limits_posix.cc b/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
index 7aca7f7e..fb932bc1 100644
--- a/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
+++ b/lib/sanitizer_common/sanitizer_platform_limits_posix.cc
@@ -168,7 +168,6 @@ namespace __sanitizer {
   unsigned struct_rlimit64_sz = sizeof(struct rlimit64);
   unsigned struct_timex_sz = sizeof(struct timex);
   unsigned struct_msqid_ds_sz = sizeof(struct msqid_ds);
-  unsigned struct_shmid_ds_sz = sizeof(struct shmid_ds);
   unsigned struct_mq_attr_sz = sizeof(struct mq_attr);
   unsigned struct_statvfs_sz = sizeof(struct statvfs);
   unsigned struct_statvfs64_sz = sizeof(struct statvfs64);
@@ -927,4 +926,25 @@ CHECK_SIZE_AND_OFFSET(mntent, mnt_passno);
 
 CHECK_TYPE_SIZE(ether_addr);
 
+#if SANITIZER_LINUX && !SANITIZER_ANDROID
+CHECK_TYPE_SIZE(ipc_perm);
+CHECK_SIZE_AND_OFFSET(ipc_perm, __key);
+CHECK_SIZE_AND_OFFSET(ipc_perm, uid);
+CHECK_SIZE_AND_OFFSET(ipc_perm, gid);
+CHECK_SIZE_AND_OFFSET(ipc_perm, cuid);
+CHECK_SIZE_AND_OFFSET(ipc_perm, cgid);
+CHECK_SIZE_AND_OFFSET(ipc_perm, mode);
+CHECK_SIZE_AND_OFFSET(ipc_perm, __seq);
+
+CHECK_TYPE_SIZE(shmid_ds);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_perm);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_segsz);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_atime);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_dtime);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_ctime);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_cpid);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_lpid);
+CHECK_SIZE_AND_OFFSET(shmid_ds, shm_nattch);
+#endif
+
 #endif  // SANITIZER_LINUX || SANITIZER_MAC
diff --git a/lib/sanitizer_common/sanitizer_platform_limits_posix.h b/lib/sanitizer_common/sanitizer_platform_limits_posix.h
index ae99403d..0b38d158 100644
--- a/lib/sanitizer_common/sanitizer_platform_limits_posix.h
+++ b/lib/sanitizer_common/sanitizer_platform_limits_posix.h
@@ -56,7 +56,6 @@ namespace __sanitizer {
   extern unsigned struct_old_utsname_sz;
   extern unsigned struct_oldold_utsname_sz;
   extern unsigned struct_msqid_ds_sz;
-  extern unsigned struct_shmid_ds_sz;
   extern unsigned struct_mq_attr_sz;
   extern unsigned struct_perf_event_attr_sz;
   extern unsigned struct_timex_sz;
@@ -86,7 +85,43 @@ namespace __sanitizer {
   extern unsigned struct_rlimit64_sz;
   extern unsigned struct_statvfs_sz;
   extern unsigned struct_statvfs64_sz;
-#endif // SANITIZER_LINUX && !SANITIZER_ANDROID
+
+  struct __sanitizer_ipc_perm {
+    int __key;
+    int uid;
+    int gid;
+    int cuid;
+    int cgid;
+    unsigned short mode;
+    unsigned short __pad1;
+    unsigned short __seq;
+    unsigned short __pad2;
+    uptr __unused1;
+    uptr __unused2;
+  };
+
+  struct __sanitizer_shmid_ds {
+    __sanitizer_ipc_perm shm_perm;
+    uptr shm_segsz;
+    uptr shm_atime;
+  #ifndef _LP64
+    uptr __unused1;
+  #endif
+    uptr shm_dtime;
+  #ifndef _LP64
+    uptr __unused2;
+  #endif
+    uptr shm_ctime;
+  #ifndef _LP64
+    uptr __unused3;
+  #endif
+    int shm_cpid;
+    int shm_lpid;
+    uptr shm_nattch;
+    uptr __unused4;
+    uptr __unused5;
+  };
+  #endif  // SANITIZER_LINUX && !SANITIZER_ANDROID
 
   struct __sanitizer_iovec {
     void  *iov_base;