patch 9.0.2068: [security] overflow in :history
Problem: [security] overflow in :history
Solution: Check that value fits into int
The get_list_range() function, used to parse numbers for the :history
and :clist command internally uses long variables to store the numbers.
However function arguments are integer pointers, which can then
overflow.
Check that the return value from the vim_str2nr() function is not larger
than INT_MAX and if yes, bail out with an error. I guess nobody uses a
cmdline/clist history that needs so many entries... (famous last words).
It is only a moderate vulnerability, so impact should be low.
Github Advisory:
https://github.com/vim/vim/security/advisories/GHSA-q22m-h7m2-9mgm
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/ex_getln.c b/src/ex_getln.c
index 9683e2e..8f0be52 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -4377,6 +4377,10 @@
{
vim_str2nr(*str, NULL, &len, 0, &num, NULL, 0, FALSE, NULL);
*str += len;
+ // overflow
+ if (num > INT_MAX)
+ return FAIL;
+
*num1 = (int)num;
first = TRUE;
}
@@ -4387,8 +4391,12 @@
vim_str2nr(*str, NULL, &len, 0, &num, NULL, 0, FALSE, NULL);
if (len > 0)
{
- *num2 = (int)num;
*str = skipwhite(*str + len);
+ // overflow
+ if (num > INT_MAX)
+ return FAIL;
+
+ *num2 = (int)num;
}
else if (!first) // no number given at all
return FAIL;