diff --git a/compiler-rt/lib/msan/tests/msan_test.cpp b/compiler-rt/lib/msan/tests/msan_test.cpp
--- a/compiler-rt/lib/msan/tests/msan_test.cpp
+++ b/compiler-rt/lib/msan/tests/msan_test.cpp
@@ -99,7 +99,8 @@
 # include <mntent.h>
 # include <netinet/ether.h>
 # if defined(__linux__)
-#  include <sys/uio.h>
+#    include <linux/fs.h>
+#    include <sys/uio.h>
 # endif
 #endif
 
@@ -706,6 +707,15 @@
   EXPECT_NOT_POISONED(ws.ws_col);
 }
 
+#if defined(__linux__)
+TEST(MemorySanitizer, DISABLED_ioctl_BLKSSZGET) {
+  int arg;
+  EXPECT_POISONED(arg);
+  EXPECT_EQ(ioctl(0, BLKSSZGET, &arg), 0);
+  EXPECT_NOT_POISONED(arg);
+}
+#endif /* defined(__linux__) */
+
 TEST(MemorySanitizer, readlink) {
   char *x = new char[1000];
   readlink(SYMLINK_TO_READ, x, 1000);
diff --git a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors_ioctl.inc b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors_ioctl.inc
--- a/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors_ioctl.inc
+++ b/compiler-rt/lib/sanitizer_common/sanitizer_common_interceptors_ioctl.inc
@@ -104,6 +104,7 @@
 #endif
 
 #if SANITIZER_LINUX
+#  include <linux/fs.h>
   // Conflicting request ids.
   // _(CDROMAUDIOBUFSIZ, NONE, 0);
   // _(SNDCTL_TMR_CONTINUE, NONE, 0);
@@ -593,6 +594,10 @@
     unsigned size = desc->size ? desc->size : IOC_SIZE(request);
     COMMON_INTERCEPTOR_WRITE_RANGE(ctx, arg, size);
   }
+#if SANITIZER_LINUX
+  if (request == BLKSSZGET)
+    COMMON_INTERCEPTOR_WRITE_RANGE(ctx, arg, sizeof(int));
+#endif  /* SANITIZER_LINUX */
   if (desc->type != ioctl_desc::CUSTOM)
     return;
   if (request == IOCTL_SIOCGIFCONF) {