From 2354d08fe9aeec3e451b85cb5387a6b28dbca0b1 Mon Sep 17 00:00:00 2001 From: Julia Lawall Date: Fri, 29 Oct 2010 15:14:18 -0400 Subject: [PATCH] Btrfs: use memdup_user helpers 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/) // @@ 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 - ...+> - } // Signed-off-by: Julia Lawall Cc: Chris Mason Signed-off-by: Andrew Morton Signed-off-by: Chris Mason --- fs/btrfs/ioctl.c | 20 ++++++-------------- 1 file changed, 6 insertions(+), 14 deletions(-) diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index db0b8fc59235..8079ebfeaf50 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -1073,14 +1073,10 @@ static noinline int btrfs_ioctl_tree_search(struct file *file, if (!capable(CAP_SYS_ADMIN)) return -EPERM; - args = kmalloc(sizeof(*args), GFP_KERNEL); - if (!args) - return -ENOMEM; + args = memdup_user(argp, sizeof(*args)); + if (IS_ERR(args)) + return PTR_ERR(args); - if (copy_from_user(args, argp, sizeof(*args))) { - kfree(args); - return -EFAULT; - } inode = fdentry(file)->d_inode; ret = search_ioctl(inode, args); if (ret == 0 && copy_to_user(argp, args, sizeof(*args))) @@ -1188,14 +1184,10 @@ static noinline int btrfs_ioctl_ino_lookup(struct file *file, if (!capable(CAP_SYS_ADMIN)) return -EPERM; - args = kmalloc(sizeof(*args), GFP_KERNEL); - if (!args) - return -ENOMEM; + args = memdup_user(argp, sizeof(*args)); + if (IS_ERR(args)) + return PTR_ERR(args); - if (copy_from_user(args, argp, sizeof(*args))) { - kfree(args); - return -EFAULT; - } inode = fdentry(file)->d_inode; if (args->treeid == 0) -- 2.20.1