PR#7039: Unix.getsockname returns garbage for unnamed PF_UNIX sockets.

Fix implemented: return ADDR_UNIX "" in this case (the file name is the empty string).

2 files changed, 10 insertions, 1 deletions

diff --git a/Changes b/Changes
index 656f17279f..030e35222b 100644
--- a/Changes
+++ b/Changes
@@ -261,6 +261,8 @@ Bug fixes:
   (report and fix by Patrick Star)
 - PR#7036: Module alias is not taken into account when checking module
   type compatibility (in a class type) (Jacques Garrigue)
+- PR#7039: Unix.getsockname returns garbage for unnamed PF_UNIX sockets
+  (Xavier Leroy)
 - GPR#205: Clear caml_backtrace_last_exn before registering as root
   (report and fix by Frederic Bour)
 - GPR#220: minor -dsource error on recursive modules
diff --git a/otherlibs/unix/socketaddr.c b/otherlibs/unix/socketaddr.c
index 2eca8fc5b8..7137848e7a 100644
--- a/otherlibs/unix/socketaddr.c
+++ b/otherlibs/unix/socketaddr.c
@@ -105,7 +105,14 @@ value alloc_sockaddr(union sock_addr_union * adr /*in*/,
   switch(adr->s_gen.sa_family) {
 #ifndef _WIN32
   case AF_UNIX:
-    { value n = copy_string(adr->s_unix.sun_path);
+    { char * path;
+      value n;
+      /* PR#7039: harden against unnamed sockets */
+      if (adr_len > (char *)&(adr->s_unix.sun_path) - (char *)&(adr->s_unix))
+        path = adr->s_unix.sun_path;
+      else
+        path = "";
+      n = copy_string(path);
       Begin_root (n);
         res = alloc_small(1, 0);
         Field(res,0) = n;