xfs: prevent a WARN_ONCE() in xfs_ioc_attr_list()

[ Upstream commit 6ed6356b07714e0198be3bc3ecccc8b40a212de4 ]

The "bufsize" comes from the root user.  If "bufsize" is negative then,
because of type promotion, neither of the validation checks at the start
of the function are able to catch it:

	if (bufsize < sizeof(struct xfs_attrlist) ||
	    bufsize > XFS_XATTR_LIST_MAX)
		return -EINVAL;

This means "bufsize" will trigger (WARN_ON_ONCE(size > INT_MAX)) in
kvmalloc_node().  Fix this by changing the type from int to size_t.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Leah Rumancik <leah.rumancik@gmail.com>
Acked-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 09269f478df9c7d04b294594e4b3a8e5ef1d2b9e..fba52e75e98b6fafbe3b29a89b1e3ad4e092758a 100644 (file)
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -372,7 +372,7 @@ int
 xfs_ioc_attr_list(
        struct xfs_inode                *dp,
        void __user                     *ubuf,
-       int                             bufsize,
+       size_t                          bufsize,
        int                             flags,
        struct xfs_attrlist_cursor __user *ucursor)
 {

diff --git a/fs/xfs/xfs_ioctl.h b/fs/xfs/xfs_ioctl.h
index 28453a6d446185bed95f2e8b324e6e5f6a98f421..845d3bcab74b407f94e660ca26e794a3aa89e5d0 100644 (file)
--- a/fs/xfs/xfs_ioctl.h
+++ b/fs/xfs/xfs_ioctl.h
@@ -38,8 +38,9 @@ xfs_readlink_by_handle(
 int xfs_ioc_attrmulti_one(struct file *parfilp, struct inode *inode,
                uint32_t opcode, void __user *uname, void __user *value,
                uint32_t *len, uint32_t flags);
-int xfs_ioc_attr_list(struct xfs_inode *dp, void __user *ubuf, int bufsize,
-       int flags, struct xfs_attrlist_cursor __user *ucursor);
+int xfs_ioc_attr_list(struct xfs_inode *dp, void __user *ubuf,
+                     size_t bufsize, int flags,
+                     struct xfs_attrlist_cursor __user *ucursor);
 
 extern struct dentry *
 xfs_handle_to_dentry(