Fix some ubsan issues: I fear no bugs were harmed in the making of this episode

4 files changed, 6 insertions, 7 deletions

diff --git a/src/core/lib/channel/channel_args.c b/src/core/lib/channel/channel_args.c
index 28d2d78d00..1659c3788b 100644
--- a/src/core/lib/channel/channel_args.c
+++ b/src/core/lib/channel/channel_args.c
@@ -132,7 +132,7 @@ grpc_channel_args *grpc_channel_args_normalize(const grpc_channel_args *a) {
   for (size_t i = 0; i < a->num_args; i++) {
     args[i] = &a->args[i];
   }
-  qsort(args, a->num_args, sizeof(grpc_arg *), cmp_key_stable);
+  if (a->num_args > 1) qsort(args, a->num_args, sizeof(grpc_arg *), cmp_key_stable);
 
   grpc_channel_args *b = gpr_malloc(sizeof(grpc_channel_args));
   b->num_args = a->num_args;
diff --git a/src/core/lib/compression/compression_algorithm.c b/src/core/lib/compression/compression_algorithm.c
index 7039364b7b..820871d579 100644
--- a/src/core/lib/compression/compression_algorithm.c
+++ b/src/core/lib/compression/compression_algorithm.c
@@ -199,5 +199,6 @@ void grpc_compression_options_disable_algorithm(
 int grpc_compression_options_is_algorithm_enabled(
     const grpc_compression_options *opts,
     grpc_compression_algorithm algorithm) {
+  if (algorithm >= GRPC_COMPRESS_ALGORITHMS_COUNT) return 0;
   return GPR_BITGET(opts->enabled_algorithms_bitset, algorithm);
 }
diff --git a/src/core/lib/support/murmur_hash.c b/src/core/lib/support/murmur_hash.c
index 5711fff0c0..7137c1f313 100644
--- a/src/core/lib/support/murmur_hash.c
+++ b/src/core/lib/support/murmur_hash.c
@@ -33,6 +33,8 @@
 
 #include "src/core/lib/support/murmur_hash.h"
 
+#include <string.h>
+
 #define ROTL32(x, r) ((x) << (r)) | ((x) >> (32 - (r)))
 
 #define FMIX32(h)    \
@@ -42,10 +44,6 @@
   (h) *= 0xc2b2ae35; \
   (h) ^= (h) >> 16;
 
-/* Block read - if your platform needs to do endian-swapping or can only
-   handle aligned reads, do the conversion here */
-#define GETBLOCK32(p, i) (p)[(i)]
-
 uint32_t gpr_murmur_hash3(const void *key, size_t len, uint32_t seed) {
   const uint8_t *data = (const uint8_t *)key;
   const size_t nblocks = len / 4;
@@ -62,7 +60,7 @@ uint32_t gpr_murmur_hash3(const void *key, size_t len, uint32_t seed) {
 
   /* body */
   for (i = -(int)nblocks; i; i++) {
-    k1 = GETBLOCK32(blocks, i);
+    memcpy(&k1, blocks + i, sizeof(uint32_t));
 
     k1 *= c1;
     k1 = ROTL32(k1, 15);
diff --git a/src/core/lib/transport/metadata.c b/src/core/lib/transport/metadata.c
index 5847ec9053..53fe03bdc9 100644
--- a/src/core/lib/transport/metadata.c
+++ b/src/core/lib/transport/metadata.c
@@ -373,7 +373,7 @@ grpc_mdstr *grpc_mdstr_from_buffer(const uint8_t *buf, size_t length) {
     ss = g_static_strtab[idx];
     if (ss == NULL) break;
     if (ss->hash == hash && GPR_SLICE_LENGTH(ss->slice) == length &&
-        0 == memcmp(buf, GPR_SLICE_START_PTR(ss->slice), length)) {
+        (length == 0 || 0 == memcmp(buf, GPR_SLICE_START_PTR(ss->slice), length))) {
       GPR_TIMER_END("grpc_mdstr_from_buffer", 0);
       return ss;
     }