From 33e4945352a2484c92fc1d5a16471b1939d67abb Mon Sep 17 00:00:00 2001 From: Jakob Koschel Date: Mon, 13 Mar 2023 14:59:19 +0100 Subject: watchdog: avoid usage of iterator after loop If potentially no valid element is found, 'p' would contain an invalid pointer past the iterator loop. To ensure 'p' is valid under any circumstances, the kfree() should be within the loop body. Additionally, Linus proposed to avoid any use of the list iterator variable after the loop, in the attempt to move the list iterator variable declaration into the macro to avoid any potential misuse after the loop [1]. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1] Signed-off-by: Jakob Koschel Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20230301-watchdog-avoid-iter-after-loop-v2-1-8411e3bbe0de@gmail.com Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/watchdog_pretimeout.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'drivers/watchdog') diff --git a/drivers/watchdog/watchdog_pretimeout.c b/drivers/watchdog/watchdog_pretimeout.c index 376a495ab80c..e5295c990fa1 100644 --- a/drivers/watchdog/watchdog_pretimeout.c +++ b/drivers/watchdog/watchdog_pretimeout.c @@ -207,10 +207,9 @@ void watchdog_unregister_pretimeout(struct watchdog_device *wdd) list_for_each_entry_safe(p, t, &pretimeout_list, entry) { if (p->wdd == wdd) { list_del(&p->entry); + kfree(p); break; } } spin_unlock_irq(&pretimeout_lock); - - kfree(p); } -- cgit v1.2.3