From 4cb57ab4a2e61978f3a9b7d4f53988f30d61c27f Mon Sep 17 00:00:00 2001 From: Mikulas Patocka Date: Thu, 5 Dec 2013 17:33:29 -0500 Subject: [PATCH] dm bufio: initialize read-only module parameters Some module parameters in dm-bufio are read-only. These parameters inform the user about memory consumption. They are not supposed to be changed by the user. However, despite being read-only, these parameters can be set on modprobe or insmod command line, for example: modprobe dm-bufio current_allocated_bytes=12345 The kernel doesn't expect that these variables can be non-zero at module initialization and if the user sets them, it results in BUG. This patch initializes the variables in the module init routine, so that user-supplied values are ignored. Signed-off-by: Mikulas Patocka Signed-off-by: Mike Snitzer Cc: stable@vger.kernel.org # 3.2+ --- drivers/md/dm-bufio.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/md/dm-bufio.c b/drivers/md/dm-bufio.c index 173cbb2..54bdd923 100644 --- a/drivers/md/dm-bufio.c +++ b/drivers/md/dm-bufio.c @@ -1717,6 +1717,11 @@ static int __init dm_bufio_init(void) { __u64 mem; + dm_bufio_allocated_kmem_cache = 0; + dm_bufio_allocated_get_free_pages = 0; + dm_bufio_allocated_vmalloc = 0; + dm_bufio_current_allocated = 0; + memset(&dm_bufio_caches, 0, sizeof dm_bufio_caches); memset(&dm_bufio_cache_names, 0, sizeof dm_bufio_cache_names); -- 2.7.4