[PATCH 3.16 115/134] ceph: fix memory leak in __ceph_setxattr()

Ben Hutchings
2017-08-18T13:13:20Z

From: Luis Henriques <lhenriques@suse.com>

commit eeca958dce0a9231d1969f86196653eb50fcc9b3 upstream.

The ceph_inode_xattr needs to be released when removing an xattr. Easily
reproducible running the 'generic/020' test from xfstests or simply by
doing:

attr -s attr0 -V 0 /mnt/test && attr -r attr0 /mnt/test

While there, also fix the error path.

Here's the kmemleak splat:

unreferenced object 0xffff88001f86fbc0 (size 64):
comm "attr", pid 244, jiffies 4294904246 (age 98.464s)
hex dump (first 32 bytes):
40 fa 86 1f 00 88 ff ff 80 32 38 1f 00 88 ff ff @........28.....
00 01 00 00 00 00 ad de 00 02 00 00 00 00 ad de ................
backtrace:
[<ffffffff81560199>] kmemleak_alloc+0x49/0xa0
[<ffffffff810f3e5b>] kmem_cache_alloc+0x9b/0xf0
[<ffffffff812b157e>] __ceph_setxattr+0x17e/0x820
[<ffffffff812b1c57>] ceph_set_xattr_handler+0x37/0x40
[<ffffffff8111fb4b>] __vfs_removexattr+0x4b/0x60
[<ffffffff8111fd37>] vfs_removexattr+0x77/0xd0
[<ffffffff8111fdd1>] removexattr+0x41/0x60
[<ffffffff8111fe65>] path_removexattr+0x75/0xa0
[<ffffffff81120aeb>] SyS_lremovexattr+0xb/0x10
[<ffffffff81564b20>] entry_SYSCALL_64_fastpath+0x13/0x94
[<ffffffffffffffff>] 0xffffffffffffffff

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
fs/ceph/xattr.c | 3 +++
1 file changed, 3 insertions(+)

--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -369,6 +369,7 @@ static int __set_xattr(struct ceph_inode

if (update_xattr) {
int err = 0;
+
if (xattr && (flags & XATTR_CREATE))
err = -EEXIST;
else if (!xattr && (flags & XATTR_REPLACE))
@@ -376,12 +377,14 @@ static int __set_xattr(struct ceph_inode
if (err) {
kfree(name);
kfree(val);
+ kfree(*newxattr);
return err;
}
if (update_xattr < 0) {
if (xattr)
__remove_xattr(ci, xattr);
kfree(name);
+ kfree(*newxattr);
return 0;
}
}