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| author | Eric Biggers <ebiggers@google.com> | 2016-12-30 17:42:32 -0600 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-01-01 11:53:34 -0500 |
| commit | e1a3a60a2ebe991605acb14cd58e39c0545e174e (patch) | |
| tree | b71f15a1e819cb409b2ccb665aae1a4e32fb399d /net/socket.c | |
| parent | f5a0aab84b74de68523599817569c057c7ac1622 (diff) | |
| download | lwn-e1a3a60a2ebe991605acb14cd58e39c0545e174e.tar.gz lwn-e1a3a60a2ebe991605acb14cd58e39c0545e174e.zip | |
net: socket: don't set sk_uid to garbage value in ->setattr()
->setattr() was recently implemented for socket files to sync the socket
inode's uid to the new 'sk_uid' member of struct sock. It does this by
copying over the ia_uid member of struct iattr. However, ia_uid is
actually only valid when ATTR_UID is set in ia_valid, indicating that
the uid is being changed, e.g. by chown. Other metadata operations such
as chmod or utimes leave ia_uid uninitialized. Therefore, sk_uid could
be set to a "garbage" value from the stack.
Fix this by only copying the uid over when ATTR_UID is set.
Fixes: 86741ec25462 ("net: core: Add a UID field to struct sock.")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Lorenzo Colitti <lorenzo@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/socket.c')
| -rw-r--r-- | net/socket.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/socket.c b/net/socket.c index 8487bf136e5c..a8c2307590b8 100644 --- a/net/socket.c +++ b/net/socket.c @@ -537,7 +537,7 @@ int sockfs_setattr(struct dentry *dentry, struct iattr *iattr) { int err = simple_setattr(dentry, iattr); - if (!err) { + if (!err && (iattr->ia_valid & ATTR_UID)) { struct socket *sock = SOCKET_I(d_inode(dentry)); sock->sk->sk_uid = iattr->ia_uid; |