From b4c233057771581698a13694ab6f33b48ce837dc Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Thu, 5 Dec 2013 17:53:50 +0300 Subject: [PATCH] mtd: sm_ftl: heap corruption in sm_create_sysfs_attributes() We always put a NUL terminator one space past the end of the "vendor" buffer. Walter Harms also pointed out that this should just use kstrndup(). Fixes: 7d17c02a01a1 ('mtd: Add new SmartMedia/xD FTL') Signed-off-by: Dan Carpenter Signed-off-by: Brian Norris --- drivers/mtd/sm_ftl.c | 11 ++++------- 1 file changed, 4 insertions(+), 7 deletions(-) diff --git a/drivers/mtd/sm_ftl.c b/drivers/mtd/sm_ftl.c index 4b8e89583f2a..cf49c22673b9 100644 --- a/drivers/mtd/sm_ftl.c +++ b/drivers/mtd/sm_ftl.c @@ -59,15 +59,12 @@ static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl) struct attribute_group *attr_group; struct attribute **attributes; struct sm_sysfs_attribute *vendor_attribute; + char *vendor; - int vendor_len = strnlen(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, - SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET); - - char *vendor = kmalloc(vendor_len, GFP_KERNEL); + vendor = kstrndup(ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, + SM_SMALL_PAGE - SM_CIS_VENDOR_OFFSET, GFP_KERNEL); if (!vendor) goto error1; - memcpy(vendor, ftl->cis_buffer + SM_CIS_VENDOR_OFFSET, vendor_len); - vendor[vendor_len] = 0; /* Initialize sysfs attributes */ vendor_attribute = @@ -78,7 +75,7 @@ static struct attribute_group *sm_create_sysfs_attributes(struct sm_ftl *ftl) sysfs_attr_init(&vendor_attribute->dev_attr.attr); vendor_attribute->data = vendor; - vendor_attribute->len = vendor_len; + vendor_attribute->len = strlen(vendor); vendor_attribute->dev_attr.attr.name = "vendor"; vendor_attribute->dev_attr.attr.mode = S_IRUGO; vendor_attribute->dev_attr.show = sm_attr_show; -- 2.30.2