BT: Fixing the rfc_slot_id overflow

Root cause:
overflow causing leak in slot fds.
As slot id 0 not valid, we are not able to release these fds later.

Fix:
Changes are made to avoid overflow while allocate rfc slots.

CRs-Fixed: 3417458
Change-Id: I5d7efa34bfb97a6dd8e9d68615d29120a0ae51f0

1 files changed, 5 insertions, 1 deletions

diff --git a/btif/src/btif_sock_rfc.cc b/btif/src/btif_sock_rfc.cc
index a4ad07349..748c1723c 100644
--- a/btif/src/btif_sock_rfc.cc
+++ b/btif/src/btif_sock_rfc.cc
@@ -215,7 +215,11 @@ static rfc_slot_t* alloc_rfc_slot(const RawAddress* addr, const char* name,
   }
 
   // Increment slot id and make sure we don't use id=0.
-  if (++rfc_slot_id == 0) rfc_slot_id = 1;
+  if (UINT32_MAX == rfc_slot_id) {
+    rfc_slot_id = 1;
+  } else {
+    ++rfc_slot_id;
+  }
 
   slot->fd = fds[0];
   slot->app_fd = fds[1];