From 2f06fa04cf35da5c24481da3ac84a2900d0b99c3 Mon Sep 17 00:00:00 2001 From: Xiubo Li Date: Sun, 28 Sep 2014 17:09:54 +0800 Subject: [PATCH] regmap: fix possible ZERO_SIZE_PTR pointer dereferencing error. commit d6b41cb06044a7d895db82bdd54f6e4219970510 upstream. Since we cannot make sure the 'val_count' will always be none zero here, and then if it equals to zero, the kmemdup() will return ZERO_SIZE_PTR, which equals to ((void *)16). So this patch fix this with just doing the zero check before calling kmemdup(). Signed-off-by: Xiubo Li Signed-off-by: Mark Brown Signed-off-by: Greg Kroah-Hartman --- drivers/base/regmap/regmap.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 5277f9a..f6cff3b 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1557,6 +1557,9 @@ int regmap_bulk_write(struct regmap *map, unsigned int reg, const void *val, } else { void *wval; + if (!val_count) + return -EINVAL; + wval = kmemdup(val, val_count * val_bytes, GFP_KERNEL); if (!wval) { ret = -ENOMEM; -- 2.7.4