On Thu, Jan 07, 2016 at 04:37:43PM +0100, Dmitry Vyukov wrote: > pass ts to the function Yeah, I should have had my morning coffee before hitting send. Updated below, and hopefully final. Checked with a test program to confirm that the huge value of seconds in timespec correctly waits, and that negative or other invalid values fail with EINVAL (download from http://www.kvack.org/~bcrl/aio-io_getevents-timespec.c ). -ben -- "Thought is the essence of where you are now." commit 49b78150bc5762c58cfb8b19a859c354cf1a71ac Author: Benjamin LaHaise <bcrl@xxxxxxxxx> Date: Thu Jan 7 10:37:58 2016 -0500 aio: handle integer overflow in io_getevents() timespec usage Dmitry Vyukov reported an integer overflow in io_getevents() when running a fuzzer. Upon investigation, the triggers appears to be that an invalid value for the tv_sec or tv_nsec was passed in which is not handled by timespec_to_ktime(). This patch fixes that by making io_getevents() return -EINVAL when timespec_valid() checks fail. We use timespec_valid() instead of timespec_valid_strict() to avoid issues caused by userspace not knowing the cutoff for KTIME_SEC_MAX. Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Signed-off-by: Benjamin LaHaise <bcrl@xxxxxxxxx> diff --git a/fs/aio.c b/fs/aio.c index 155f842..e0d5398 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1269,6 +1269,8 @@ static long read_events(struct kioctx *ctx, long min_nr, long nr, if (unlikely(copy_from_user(&ts, timeout, sizeof(ts)))) return -EFAULT; + if (!timespec_valid(&ts)) + return -EINVAL; until = timespec_to_ktime(ts); } -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
