From: Li Nan linan122@huawei.com
[ Upstream commit 6beb489b2eed25978523f379a605073f99240c50 ]
There is no input check when echo md/safe_mode_delay in safe_delay_store(). And msec might also overflow when HZ < 1000 in safe_delay_show(), Fix it by checking overflow in safe_delay_store() and use unsigned long conversion in safe_delay_show().
Fixes: 72e02075a33f ("md: factor out parsing of fixed-point numbers") Signed-off-by: Li Nan linan122@huawei.com Signed-off-by: Song Liu song@kernel.org Link: https://lore.kernel.org/r/20230522072535.1523740-2-linan666@huaweicloud.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/md.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c index 69d1501d9160e..f2f3b42e44287 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3647,8 +3647,9 @@ int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale) static ssize_t safe_delay_show(struct mddev *mddev, char *page) { - int msec = (mddev->safemode_delay*1000)/HZ; - return sprintf(page, "%d.%03d\n", msec/1000, msec%1000); + unsigned int msec = ((unsigned long)mddev->safemode_delay*1000)/HZ; + + return sprintf(page, "%u.%03u\n", msec/1000, msec%1000); } static ssize_t safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len) @@ -3660,7 +3661,7 @@ safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len) return -EINVAL; }
- if (strict_strtoul_scaled(cbuf, &msec, 3) < 0) + if (strict_strtoul_scaled(cbuf, &msec, 3) < 0 || msec > UINT_MAX / HZ) return -EINVAL; if (msec == 0) mddev->safemode_delay = 0;