patch 7.4.2323
Problem: Using freed memory when using 'formatexpr'. (Dominique Pelle)
Solution: Make a copy of 'formatexpr' before evaluating it.
diff --git a/src/ops.c b/src/ops.c
index c03c7be..4bef6c5 100644
--- a/src/ops.c
+++ b/src/ops.c
@@ -4741,6 +4741,7 @@
int use_sandbox = was_set_insecurely((char_u *)"formatexpr",
OPT_LOCAL);
int r;
+ char_u *fex;
/*
* Set v:lnum to the first line number and v:count to the number of lines.
@@ -4750,16 +4751,22 @@
set_vim_var_nr(VV_COUNT, count);
set_vim_var_char(c);
+ /* Make a copy, the option could be changed while calling it. */
+ fex = vim_strsave(curbuf->b_p_fex);
+ if (fex == NULL)
+ return 0;
+
/*
* Evaluate the function.
*/
if (use_sandbox)
++sandbox;
- r = (int)eval_to_number(curbuf->b_p_fex);
+ r = (int)eval_to_number(fex);
if (use_sandbox)
--sandbox;
set_vim_var_string(VV_CHAR, NULL, -1);
+ vim_free(fex);
return r;
}