vim-patch:8.1.1895: using NULL pointer when out of memory

Problem:    Using NULL pointer when out of memory.
Solution:   Bail out or skip the code using the pointer. (Zu-Ming Jiang,
            closes vim/vim#4805, closes vim/vim#4843, closes vim/vim#4939, closes vim/vim#4844)
https://github.com/vim/vim/commit/6f10c70b59fa4e56aa479345fb0caeaac7429bfb

2 files changed, 10 insertions, 5 deletions

diff --git a/src/nvim/buffer.c b/src/nvim/buffer.c
index 7c8f93163a..3ce39feda5 100644
--- a/src/nvim/buffer.c
+++ b/src/nvim/buffer.c
@@ -186,14 +186,17 @@ int open_buffer(
       }
     }
 
-    /*
-     * if there is no memfile at all, exit
-     * This is OK, since there are no changes to lose.
-     */
+    // If there is no memfile at all, exit.
+    // This is OK, since there are no changes to lose.
     if (curbuf == NULL) {
       EMSG(_("E82: Cannot allocate any buffer, exiting..."));
+
+      // Don't try to do any saving, with "curbuf" NULL almost nothing
+      // will work.
+      v_dying = 2;
       getout(2);
     }
+
     EMSG(_("E83: Cannot allocate buffer, using other one..."));
     enter_buffer(curbuf);
     if (old_tw != curbuf->b_p_tw) {
diff --git a/src/nvim/syntax.c b/src/nvim/syntax.c
index ef4dfb3caa..f3b05c3961 100644
--- a/src/nvim/syntax.c
+++ b/src/nvim/syntax.c
@@ -7444,6 +7444,8 @@ static int syn_add_group(char_u *name)
     return 0;
   }
 
+  char_u *const name_up = vim_strsave_up(name);
+
   // Append another syntax_highlight entry.
   struct hl_group* hlgp = GA_APPEND_VIA_PTR(struct hl_group, &highlight_ga);
   memset(hlgp, 0, sizeof(*hlgp));
@@ -7452,7 +7454,7 @@ static int syn_add_group(char_u *name)
   hlgp->sg_rgb_fg = -1;
   hlgp->sg_rgb_sp = -1;
   hlgp->sg_blend = -1;
-  hlgp->sg_name_u = vim_strsave_up(name);
+  hlgp->sg_name_u = name_up;
 
   return highlight_ga.ga_len;               /* ID is index plus one */
 }