c->error_limit is in type unsigned int, it is set via cache set sysfs file io_error_limit. Inside the bcache code, input string is converted by strtoul_or_return() and set the converted value to c->error_limit. Because the converted value is unsigned long, and c->error_limit is unsigned int, if the input is large enought, overflow will happen to c->error_limit. This patch uses sysfs_strtoul_clamp() to convert input string, and set the range in [0, UINT_MAX] to avoid the potential overflow. Signed-off-by: Coly Li <colyli@xxxxxxx> --- drivers/md/bcache/sysfs.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/md/bcache/sysfs.c b/drivers/md/bcache/sysfs.c index 032d108d3041..c9888c45cb03 100644 --- a/drivers/md/bcache/sysfs.c +++ b/drivers/md/bcache/sysfs.c @@ -789,8 +789,7 @@ STORE(__bch_cache_set) c->on_error = v; } - if (attr == &sysfs_io_error_limit) - c->error_limit = strtoul_or_return(buf); + sysfs_strtoul_clamp(io_error_limit, c->error_limit, 0, UINT_MAX); /* See count_io_errors() for why 88 */ if (attr == &sysfs_io_error_halflife) -- 2.16.4
