diff options
author | Pietro Borrello <borrello@diag.uniroma1.it> | 2023-02-04 17:39:22 +0000 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2023-02-06 10:16:55 +0000 |
commit | 66b2c338adce580dfce2199591e65e2bab889cff (patch) | |
tree | db2d69568ee3cbce31d03565f18468eb6f63f628 /drivers/net/tap.c | |
parent | a096ccca6e503a5c575717ff8a36ace27510ab0a (diff) |
tap: tap_open(): correctly initialize socket uid
sock_init_data() assumes that the `struct socket` passed in input is
contained in a `struct socket_alloc` allocated with sock_alloc().
However, tap_open() passes a `struct socket` embedded in a `struct
tap_queue` allocated with sk_alloc().
This causes a type confusion when issuing a container_of() with
SOCK_INODE() in sock_init_data() which results in assigning a wrong
sk_uid to the `struct sock` in input.
On default configuration, the type confused field overlaps with
padding bytes between `int vnet_hdr_sz` and `struct tap_dev __rcu
*tap` in `struct tap_queue`, which makes the uid of all tap sockets 0,
i.e., the root one.
Fix the assignment by using sock_init_data_uid().
Fixes: 86741ec25462 ("net: core: Add a UID field to struct sock.")
Signed-off-by: Pietro Borrello <borrello@diag.uniroma1.it>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/tap.c')
-rw-r--r-- | drivers/net/tap.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/tap.c b/drivers/net/tap.c index a2be1994b389..8941aa199ea3 100644 --- a/drivers/net/tap.c +++ b/drivers/net/tap.c @@ -533,7 +533,7 @@ static int tap_open(struct inode *inode, struct file *file) q->sock.state = SS_CONNECTED; q->sock.file = file; q->sock.ops = &tap_socket_ops; - sock_init_data(&q->sock, &q->sk); + sock_init_data_uid(&q->sock, &q->sk, inode->i_uid); q->sk.sk_write_space = tap_sock_write_space; q->sk.sk_destruct = tap_sock_destruct; q->flags = IFF_VNET_HDR | IFF_NO_PI | IFF_TAP; |