From: Matthew Wilcox <willy@infradead.org>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Changming <charley.ashbringer@gmail.com>,
rdunlap@infradead.org, keescook@chromium.org, mcgrof@kernel.org,
yzaikin@google.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2] panic: prevent panic_timeout * 1000 from overflow
Date: Tue, 14 Jul 2020 03:50:58 +0100 [thread overview]
Message-ID: <20200714025058.GZ12769@casper.infradead.org> (raw)
In-Reply-To: <20200713185739.03d576cca0dc9f618ea76d67@linux-foundation.org>
On Mon, Jul 13, 2020 at 06:57:39PM -0700, Andrew Morton wrote:
> +++ a/kernel/panic.c
> @@ -313,13 +313,16 @@ void panic(const char *fmt, ...)
> * Delay timeout seconds before rebooting the machine.
> * We can't use the "normal" timers since we just panicked.
> */
> + u64 timeout = panic_timeout * 1000; /* avoid overflow */
1000ULL to not truncate before the assignment.
> + u64 timer;
... as you implied later
u64 timer, timer_next;
> (untested)
Well, there's the rub. Testing requires 49 days (2^32 / 1000 seconds).
next prev parent reply other threads:[~2020-07-14 2:51 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <0d4601d65709a0e2d80e2a8880gmail.com>
2020-07-11 5:17 ` Changming
2020-07-14 1:57 ` Andrew Morton
2020-07-14 2:50 ` Matthew Wilcox [this message]
2020-07-16 23:15 ` [PATCH v3] " Changming Liu
2020-07-16 4:48 ` [PATCH v2] " charley.ashbringer
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