From dab71b2db98dcdd4657d151b01a7be88ce10f9d1 Mon Sep 17 00:00:00 2001 From: Coly Li Date: Sat, 9 Feb 2019 12:53:07 +0800 Subject: [PATCH] bcache: fix input overflow to writeback_rate_minimum 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 Signed-off-by: Jens Axboe --- 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 c6677c93e368..d292eb757ac4 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -308,7 +308,9 @@ 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); -- 2.25.1