c->journal_delay_ms is in type unsigned short, it is set via sysfs interface and converted by sysfs_strtoul() from input string to unsigned short value. Therefore overflow to unsigned short might be happen when the converted value exceed USHRT_MAX. e.g. writing 65536 into sysfs file journal_delay_ms, c->journal_delay_ms is set to 0.
This patch uses sysfs_strtoul_clamp() to convert the input string and limit value range in [0, USHRT_MAX], to avoid the input overflow. Signed-off-by: Coly Li <[email protected]> --- 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 d292eb757ac4..201e85bbe3eb 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -821,7 +821,9 @@ STORE(__bch_cache_set) } } - sysfs_strtoul(journal_delay_ms, c->journal_delay_ms); + sysfs_strtoul_clamp(journal_delay_ms, + c->journal_delay_ms, + 0, USHRT_MAX); sysfs_strtoul_bool(verify, c->verify); sysfs_strtoul_bool(key_merging_disabled, c->key_merging_disabled); sysfs_strtoul(expensive_debug_checks, c->expensive_debug_checks); -- 2.16.4
