philippelh/bitchx
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Fix a double-free bug when a window on an alternate screen queries an exec process

Browse Source 
The 'free_it' variable was only initialised to zero at the start of the function, so when non-main screens
were processed in the later iterations of the loop, it could keep a value of 1 from the previous iteration.

We don't actually need a free_it variable at all - just use a NULL value of ptr_free to indicate that there
is nothing to free (and passing a NULL to new_free() is a no-op).

This also simplifies a test because ptr is always non-NULL (strip_ansi() never returns NULL).
This commit is contained in:
Kevin Easton
2017-02-16 23:12:38 +11:00
parent 790cb771ed
commit debfebf3a7
2 changed files with 12 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

24
source/input.c
View File

@@ -166,10 +166,9 @@ extern void BX_cursor_to_input (void)
*/
extern void BX_update_input (int update)
{
int old_zone;
char *ptr, *ptr_free;
int old_zone;
char *ptr;
int len,
free_it = 0,
echo = 1,
max;
@@ -178,7 +177,6 @@ extern void BX_update_input (int update)
Screen *ns;
Window *saved_current_window = current_window;
#ifdef WANT_HEBREW
void BX_set_input_heb (char *str);
char prehebbuff[2000];
@@ -230,32 +228,29 @@ extern void BX_update_input (int update)
if (prompt && update != NO_UPDATE)
{
int args_used;
int args_used;
char *ptr_free = NULL;
if (is_valid_process(get_target_by_refnum(0)) != -1)
ptr = (char *)get_prompt_by_refnum(0);
else
{
ptr = expand_alias(prompt, empty_string, &args_used, NULL);
free_it = 1;
ptr_free = ptr;
}
if (last_input_screen->promptlist)
term_echo(last_input_screen->promptlist->echo);
ptr_free = ptr;
ptr = strip_ansi(ptr);
strcat(ptr, ALL_OFF_STR); /* Yes, we can do this */
if (free_it)
new_free(&ptr_free);
free_it = 1;
new_free(&ptr_free);
if ((ptr && !INPUT_LINE) || (!ptr && INPUT_LINE) ||
strcmp(ptr, last_input_screen->input_buffer))
if (!INPUT_LINE || strcmp(ptr, last_input_screen->input_buffer))
{
if (last_input_screen->input_prompt_malloc)
new_free(&INPUT_PROMPT);
last_input_screen->input_prompt_malloc = free_it;
last_input_screen->input_prompt_malloc = 1;
INPUT_PROMPT = ptr;
len = strlen(INPUT_PROMPT);
@@ -264,8 +259,7 @@ extern void BX_update_input (int update)
}
else
{
if (free_it)
new_free(&ptr);
new_free(&ptr);
}
}