Problem: [security]: prevent overflow in indenting
Solution: use long long and remove cast to (int)
The shiftwidth option values are defined as being long. However, when
calculating the actual amount of indent, we cast down to (int), which
may cause the shiftwidth value to become negative and later it may even
cause Vim to try to allocate a huge amount of memory.
We already use long and long long variable types to calculate the indent
(and detect possible overflows), so the cast to (int) seems superfluous
and can be safely removed. So let's just remove the (int) cast and
calculate the indent using longs.
Additionally, the 'shiftwidth' option value is also used when determining
the actual 'cino' options. There it can again cause another overflow, so
make sure it is safe in parse_cino() as well.
fixes: #13554closes: #13555
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: [security]: overflow in shift_line
Solution: allow a max indent of INT_MAX
[security]: overflow in shift_line
When shifting lines in operator pending mode and using a very large
value, we may overflow the size of integer. Fix this by using a long
variable, testing if the result would be larger than INT_MAX and if so,
indent by INT_MAX value.
Special case: We cannot use long here, since on 32bit architectures (or
on Windows?), it typically cannot take larger values than a plain int,
so we have to use long long count, decide whether the resulting
multiplication of the shiftwidth value * amount is larger than INT_MAX
and if so, we will store INT_MAX as possible larges value in the long
long count variable.
Then we can safely cast it back to int when calling the functions to set
the indent (set_indent() or change_indent()). So this should be safe.
Add a test that when using a huge value in operator pending mode for
shifting, we will shift by INT_MAX
closes: #13535
Signed-off-by: Christian Brabandt <cb@256bit.org>
Problem: When re-formatting with an indent expression the first line of a
paragraph may get the wrong indent. (Martin F. Krafft)
Solution: Apply the correct indenting function for the first line.
(Christian Brabandt, closes#9150, closes#9056)
