From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pb0-f49.google.com ([209.85.160.49]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1T5BN3-0002Nh-5J for linux-mtd@lists.infradead.org; Sat, 25 Aug 2012 08:05:30 +0000 Received: by pbbrq8 with SMTP id rq8so4901617pbb.36 for ; Sat, 25 Aug 2012 01:05:28 -0700 (PDT) From: Huang Shijie To: dwmw2@infradead.org Subject: [PATCH v2] mtd: cmdlinepart: fix the wrong check condition Date: Sat, 25 Aug 2012 16:06:50 -0400 Message-Id: <1345925210-7500-1-git-send-email-shijie8@gmail.com> Cc: Huang Shijie , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org, dedekind1@gmail.com List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , The `mtd_id` is set by the name of a mtd device driver. As a nand controller driver, even we do not set the @name of the mtd_info{}, the nand_get_flash_type() will set it with the nand type's name. So the `mtd_id` can never be NULL in this case. But as a nor controller driver which may does not call the nand_get_flash_type(), there is a risk that the `mtd_id` becames NULL. If the `mtd_id` is NULL, the check condition will be true. If we accidentally set some partitions in the kernel command line, just like: #gpmi-nand:20m(boot),20m(kernel),1g(rootfs),-(user) The cmdlinepart may parses out several mtd partitions right now. This is obviously wrong. We even do not enable the gpmi-nand in this case. The patch comes from Artem's suggestion code which is better then mine. Signed-off-by: Huang Shijie --- drivers/mtd/cmdlinepart.c | 5 ++++- 1 files changed, 4 insertions(+), 1 deletions(-) diff --git a/drivers/mtd/cmdlinepart.c b/drivers/mtd/cmdlinepart.c index fc960a3..216d751 100644 --- a/drivers/mtd/cmdlinepart.c +++ b/drivers/mtd/cmdlinepart.c @@ -322,13 +322,16 @@ static int parse_cmdline_partitions(struct mtd_info *master, struct cmdline_mtd_partition *part; const char *mtd_id = master->name; + if (!mtd_id) + return 0; + /* parse command line */ if (!cmdline_parsed) mtdpart_setup_real(cmdline); for(part = partitions; part; part = part->next) { - if ((!mtd_id) || (!strcmp(part->mtd_id, mtd_id))) + if (!strcmp(part->mtd_id, mtd_id)) { for(i = 0, offset = 0; i < part->num_parts; i++) { -- 1.7.4.4