From: Coly Li <colyli@xxxxxxx> [ Upstream commit dab71b2db98dcdd4657d151b01a7be88ce10f9d1 ] dc->writeback_rate_minimum is type unsigned integer variable, it is set via sysfs interface, and converte from input string to unsigned integer by d_strtoul_nonzero(). When the converted input value is larger than UINT_MAX, overflow to unsigned integer happens. This patch fixes the overflow by using sysfs_strotoul_clamp() to convert input string and limit the value in range [1, UINT_MAX], then the overflow can be avoided. Signed-off-by: Coly Li <colyli@xxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/md/bcache/sysfs.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index 5bb81e564ce88..3e8d1f1b562f8 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -289,7 +289,9 @@ STORE(__cached_dev) sysfs_strtoul_clamp(writeback_rate_p_term_inverse, dc->writeback_rate_p_term_inverse, 1, UINT_MAX); - d_strtoul_nonzero(writeback_rate_minimum); + sysfs_strtoul_clamp(writeback_rate_minimum, + dc->writeback_rate_minimum, + 1, UINT_MAX); sysfs_strtoul_clamp(io_error_limit, dc->error_limit, 0, INT_MAX); -- 2.20.1
