[PATCH] mtd: check parts pointer before using it
From: Jamie Iles <hidden>
Date: 2011-08-24 11:08:40
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Hi Jason, On Wed, Aug 24, 2011 at 06:53:01PM +0800, Jason Liu wrote:
quoted hunk ↗ jump to hunk
The code has the check for parts but it called after kmemdup, kmemdup(parts, sizeof(*parts) * nr_parts,...) if (!parts) return -ENOMEM In fact, we need check parts before safely using it. Signed-off-by: Jason Liu <redacted> Cc: Dmitry Eremin-Solenikov <redacted> Cc: Artem Bityutskiy <redacted> --- This patch is based on git://git.infradead.org/users/dedekind/l2-mtd-2.6.git --- drivers/mtd/mtdcore.c | 4 +--- 1 files changed, 1 insertions(+), 3 deletions(-)diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c index 09bdbac..ce59ff5 100644 --- a/drivers/mtd/mtdcore.c +++ b/drivers/mtd/mtdcore.c@@ -465,12 +465,10 @@ int mtd_device_parse_register(struct mtd_info *mtd, const char **types, struct mtd_partition *real_parts; err = parse_mtd_partitions(mtd, types, &real_parts, parser_data); - if (err <= 0 && nr_parts) { + if (err <= 0 && nr_parts && !parts) {
I don't think this is right. Don't we want to check that parts is != NULL? So if (err <= 0 && nr_parts && parts) instead? We don't want to kmemdup() NULL.
real_parts = kmemdup(parts, sizeof(*parts) * nr_parts, GFP_KERNEL); err = nr_parts; - if (!parts) - err = -ENOMEM;
I think this hunk should be changed to: if (!real_parts) err = -ENOMEM; and keep the check so that we're checking kmemdup()'s allocation is successful. Jamie