From f54478c6e226bb1540a3e58366601039dfd778e2 Mon Sep 17 00:00:00 2001
From: Coly Li <colyli@suse.de>
Date: Sat, 9 Feb 2019 12:53:00 +0800
Subject: [PATCH] bcache: fix input integer overflow of congested threshold
Git-commit: f54478c6e226bb1540a3e58366601039dfd778e2
Patch-mainline: v5.1-rc1
References: bsc#1130972
Cache set congested threshold values congested_read_threshold_us and
congested_write_threshold_us can be set via sysfs interface. These
two values are 'unsigned int' type, but sysfs interface uses strtoul
to convert input string. So if people input a large number like
9999999999, the value indeed set is 1410065407, which is not expected
behavior.
This patch replaces sysfs_strtoul() by sysfs_strtoul_clamp() when
convert input string to unsigned int value, and set value range in
[0, UINT_MAX], to avoid the above integer overflow errors.
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
drivers/md/bcache/sysfs.c | 10 ++++++----
1 file changed, 6 insertions(+), 4 deletions(-)
diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c
index 9be27b26d300..bedd3e68fd29 100644
--- a/drivers/md/bcache/sysfs.c
+++ b/drivers/md/bcache/sysfs.c
@@ -778,10 +778,12 @@ STORE(__bch_cache_set)
c->shrink.scan_objects(&c->shrink, &sc);
}
- sysfs_strtoul(congested_read_threshold_us,
- c->congested_read_threshold_us);
- sysfs_strtoul(congested_write_threshold_us,
- c->congested_write_threshold_us);
+ sysfs_strtoul_clamp(congested_read_threshold_us,
+ c->congested_read_threshold_us,
+ 0, UINT_MAX);
+ sysfs_strtoul_clamp(congested_write_threshold_us,
+ c->congested_write_threshold_us,
+ 0, UINT_MAX);
if (attr == &sysfs_errors) {
v = __sysfs_match_string(error_actions, -1, buf);
--
2.16.4