mm/zpool: use prefixed module loading

To avoid potential format string expansion via module parameters, do not
use the zpool type directly in request_module() without a format string.
Additionally, to avoid arbitrary modules being loaded via zpool API
(e.g.  via the zswap_zpool_type module parameter) add a "zpool-" prefix
to the requested module, as well as module aliases for the existing
zpool types (zbud and zsmalloc).

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Seth Jennings <sjennings@variantweb.net>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Nitin Gupta <ngupta@vflare.org>
Acked-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 137f8cff505ace6251dc442c7aa973d60c801a79)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
 Conflicts:
	mm/zbud.c

 Conflicts solution:
	remove zbud

diff --git a/mm/zpool.c b/mm/zpool.c
index e40612a1df00b62c9a9728867d45fd7275bb2b0f..739cdf0d183ac0e51571d16f5b6321ccc837e7d1 100644 (file)
--- a/mm/zpool.c
+++ b/mm/zpool.c
@@ -150,7 +150,7 @@ struct zpool *zpool_create_pool(char *type, gfp_t gfp, struct zpool_ops *ops)
        driver = zpool_get_driver(type);
 
        if (!driver) {
-               request_module(type);
+               request_module("zpool-%s", type);
                driver = zpool_get_driver(type);
        }
 

diff --git a/mm/zsmalloc.c b/mm/zsmalloc.c
index fc25b58a02f81bbc6031c8139bf6bdd88e82cc38..f40ff48433e2743d8b8fbc60409303d45ba390ec 100644 (file)
--- a/mm/zsmalloc.c
+++ b/mm/zsmalloc.c
@@ -314,6 +314,7 @@ static struct zpool_driver zs_zpool_driver = {
        .total_size =   zs_zpool_total_size,
 };
 
+MODULE_ALIAS("zpool-zsmalloc");
 #endif /* CONFIG_ZPOOL */
 
 /* per-cpu VM mapping areas for zspage accesses that cross page boundaries */