From: Julia Lawall <julia@xxxxxxx> Use memdup_user when user data is immediately copied into the allocated region. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @@ expression from,to,size,flag; position p; identifier l1,l2; @@ - to = \(kmalloc@p\|kzalloc@p\)(size,flag); + to = memdup_user(from,size); if ( - to==NULL + IS_ERR(to) || ...) { <+... when != goto l1; - -ENOMEM + PTR_ERR(to) ...+> } - if (copy_from_user(to, from, size) != 0) { - <+... when != goto l2; - -EFAULT - ...+> - } // </smpl> Signed-off-by: Julia Lawall <julia@xxxxxxx> --- mm/util.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/mm/util.c b/mm/util.c index f5712e8..4735ea4 100644 --- a/mm/util.c +++ b/mm/util.c @@ -225,15 +225,10 @@ char *strndup_user(const char __user *s, long n) if (length > n) return ERR_PTR(-EINVAL); - p = kmalloc(length, GFP_KERNEL); + p = memdup_user(s, length); - if (!p) - return ERR_PTR(-ENOMEM); - - if (copy_from_user(p, s, length)) { - kfree(p); - return ERR_PTR(-EFAULT); - } + if (IS_ERR(p)) + return p; p[length - 1] = '\0'; -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
