Handle SIGPROT, CHERI's in-address space security exception

m4/ax_check_catchable_segv.m4

@@ -21,6 +21,9 @@ static void sig(int _) { exit(0); }
 volatile unsigned char * volatile x = (volatile unsigned char *) malloc(8);
 size_t i;
 
+#ifdef SIGPROT
+signal(SIGPROT, sig);
+#endif
 signal(SIGSEGV, sig);
 signal(SIGBUS, sig);
 #if !defined(__SANITIZE_ADDRESS__) && !defined(__EMSCRIPTEN__)

src/libsodium/sodium/utils.c

@@ -82,6 +82,7 @@ void *alloca (size_t);
     defined(HAVE_POSIX_MEMALIGN)
 # define HAVE_ALIGNED_MALLOC
 #endif
+
 #if defined(HAVE_MPROTECT) && \
     !(defined(PROT_NONE) && defined(PROT_READ) && defined(PROT_WRITE))
 # undef HAVE_MPROTECT
@@ -510,7 +511,9 @@ __attribute__((noreturn)) static void
 _out_of_bounds(void)
 {
 # if defined(HAVE_RAISE) && !defined(__wasm__)
-#  ifdef SIGSEGV
+#  ifdef SIGPROT
+    raise(SIGPROT);
+#  elif defined(SIGSEGV)
     raise(SIGSEGV);
 #  elif defined(SIGKILL)
     raise(SIGKILL);

test/default/sodium_utils2.c

@@ -29,6 +29,9 @@ segv_handler(int sig)
     printf("Intentional segfault / bus error caught\n");
     printf("OK\n");
 #ifdef SIG_DFL
+# ifdef SIGPROT
+    signal(SIGPROT, SIG_DFL);
+# endif
 # ifdef SIGSEGV
     signal(SIGSEGV, SIG_DFL);
 # endif
@@ -82,6 +85,9 @@ main(void)
     }
     printf("OK\n");
 #ifdef SIG_DFL
+# ifdef SIGPROT
+    signal(SIGPROT, segv_handler);
+# endif
 # ifdef SIGSEGV
     signal(SIGSEGV, segv_handler);
 # endif

test/default/sodium_utils3.c

@@ -25,6 +25,9 @@ segv_handler(int sig)
     printf("Intentional segfault / bus error caught\n");
     printf("OK\n");
 #ifdef SIG_DFL
+# ifdef SIGPROT
+    signal(SIGPROT, SIG_DFL);
+# endif
 # ifdef SIGSEGV
     signal(SIGSEGV, SIG_DFL);
 # endif
@@ -49,6 +52,9 @@ main(void)
 #endif
 
 #ifdef SIG_DFL
+# ifdef SIGPROT
+    signal(SIGPROT, segv_handler);
+# endif
 # ifdef SIGSEGV
     signal(SIGSEGV, segv_handler);
 # endif