Patch "fuse: listxattr: verify xattr list" has been added to the 4.7-stable tree
From: <gregkh@linuxfoundation.org>
Date: 2016-10-20 14:24:29
This is a note to let you know that I've just added the patch titled
fuse: listxattr: verify xattr list
to the 4.7-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fuse-listxattr-verify-xattr-list.patch
and it can be found in the queue-4.7 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let [off-list ref] know about it.
From cb3ae6d25a5471be62bfe6ac1fccc0e91edeaba0 Mon Sep 17 00:00:00 2001
From: Miklos Szeredi <redacted> Date: Sat, 1 Oct 2016 07:32:32 +0200 Subject: fuse: listxattr: verify xattr list From: Miklos Szeredi <redacted> commit cb3ae6d25a5471be62bfe6ac1fccc0e91edeaba0 upstream. Make sure userspace filesystem is returning a well formed list of xattr names (zero or more nonzero length, null terminated strings). [Michael Theall: only verify in the nonzero size case] Signed-off-by: Miklos Szeredi <redacted> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> --- fs/fuse/dir.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+)
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c@@ -1800,6 +1800,23 @@ static ssize_t fuse_getxattr(struct dent return ret; } +static int fuse_verify_xattr_list(char *list, size_t size) +{ + size_t origsize = size; + + while (size) { + size_t thislen = strnlen(list, size); + + if (!thislen || thislen == size) + return -EIO; + + size -= thislen + 1; + list += thislen + 1; + } + + return origsize; +} + static ssize_t fuse_listxattr(struct dentry *entry, char *list, size_t size) { struct inode *inode = d_inode(entry);
@@ -1835,6 +1852,8 @@ static ssize_t fuse_listxattr(struct den ret = fuse_simple_request(fc, &args); if (!ret && !size) ret = outarg.size; + if (ret > 0 && size) + ret = fuse_verify_xattr_list(list, ret); if (ret == -ENOSYS) { fc->no_listxattr = 1; ret = -EOPNOTSUPP;
Patches currently in stable-queue which might be from mszeredi@redhat.com are queue-4.7/fuse-listxattr-verify-xattr-list.patch queue-4.7/fuse-invalidate-dir-dentry-after-chmod.patch queue-4.7/fuse-fix-killing-sid-in-setattr.patch