dm-pcache: fix implicit u8 truncation of gc_percent in message handler

When setting gc_percent via message, kstrtoul parses the input into an
unsigned long, which is then implicitly truncated to u8 when passed to
pcache_cache_set_gc_percent(). For example, value 266 (0x10A) silently
truncates to 10 (0x0A), successfully bypassing the > 90 upper bound
check in pcache_cache_set_gc_percent(), and setting a different value
than the user intended.

Use kstrtou8 directly instead of kstrtoul, so that overflow values are
properly rejected.

Cc: stable@vger.kernel.org
Fixes: 1d57628ff95b ("dm-pcache: add persistent cache target in device-mapper")
Signed-off-by: Jianyun Gao <jianyungao89@gmail.com>
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>

0 files changed, 0 insertions, 0 deletions