linux-dev/net/x25, branch master

net/x25: fix call timeouts in blocking connects

2022-08-09T03:48:51Z

When a userspace application starts a blocking connect(), a CALL REQUEST is sent, the t21 timer is started and the connect is waiting in x25_wait_for_connection_establishment(). If then for some reason the t21 timer expires before any reaction on the assigned logical channel (e.g. CALL ACCEPT, CLEAR REQUEST), there is sent a CLEAR REQUEST and timer t23 is started waiting for a CLEAR confirmation. If we now receive a CLEAR CONFIRMATION from the peer, x25_disconnect() is called in x25_state2_machine() with reason "0", which means "normal" call clearing. This is ok, but the parameter "reason" is used as sk->sk_err in x25_disconnect() and sock_error(sk) is evaluated in x25_wait_for_connection_establishment() to check if the call is still pending. As "0" is not rated as an error, the connect will stuck here forever. To fix this situation, also check if the sk->sk_state changed form TCP_SYN_SENT to TCP_CLOSE in the meantime, which is also done by x25_disconnect(). Signed-off-by: Martin Schiller Link: https://lore.kernel.org/r/20220805061810.10824-1-ms@dev.tdt.de Signed-off-by: Jakub Kicinski

x25: remove redundant pointer dev

2022-05-10T09:59:22Z

Pointer dev is being assigned a value that is never used, the assignment and the variable are redundant and can be removed. Also replace null check with the preferred !ptr idiom. Cleans up clang scan warning: net/x25/x25_proc.c:94:26: warning: Although the value stored to 'dev' is used in the enclosing expression, the value is never actually read from 'dev' [deadcode.DeadStores] Signed-off-by: Colin Ian King Link: https://lore.kernel.org/r/20220508214500.60446-1-colin.i.king@gmail.com Signed-off-by: Paolo Abeni

net: remove noblock parameter from skb_recv_datagram()

2022-04-06T12:45:26Z

skb_recv_datagram() has two parameters 'flags' and 'noblock' that are merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)' As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags' into 'flags' and 'noblock' with finally obsolete bit operations like this: skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc); And this is not even done consistently with the 'flags' parameter. This patch removes the obsolete and costly splitting into two parameters and only performs bit operations when really needed on the caller side. One missing conversion thankfully reported by kernel test robot. I missed to enable kunit tests to build the mctp code. Reported-by: kernel test robot Signed-off-by: Oliver Hartkopp Signed-off-by: David S. Miller

net/x25: Fix null-ptr-deref caused by x25_disconnect

2022-03-26T18:48:16Z

When the link layer is terminating, x25->neighbour will be set to NULL in x25_disconnect(). As a result, it could cause null-ptr-deref bugs in x25_sendmsg(),x25_recvmsg() and x25_connect(). One of the bugs is shown below. (Thread 1) | (Thread 2) x25_link_terminated() | x25_recvmsg() x25_kill_by_neigh() | ... x25_disconnect() | lock_sock(sk) ... | ... x25->neighbour = NULL //(1) | ... | x25->neighbour->extended //(2) The code sets NULL to x25->neighbour in position (1) and dereferences x25->neighbour in position (2), which could cause null-ptr-deref bug. This patch adds lock_sock() in x25_kill_by_neigh() in order to synchronize with x25_sendmsg(), x25_recvmsg() and x25_connect(). What`s more, the sock held by lock_sock() is not NULL, because it is extracted from x25_list and uses x25_list_lock to synchronize. Fixes: 4becb7ee5b3d ("net/x25: Fix x25_neigh refcnt leak when x25 disconnect") Signed-off-by: Duoming Zhou Reviewed-by: Lin Ma Signed-off-by: David S. Miller

net: x25: drop harmless check of !more

2021-12-10T02:35:11Z

'more' is checked first. When !more is checked immediately after that, it is always true. We should drop this check. Signed-off-by: Jean Sacren Acked-by: Martin Schiller Link: https://lore.kernel.org/r/20211208024732.142541-5-sakiwit@gmail.com Signed-off-by: Jakub Kicinski

net: x25: Use list_for_each_entry() to simplify code in x25_route.c

2021-06-10T21:08:09Z

Convert list_for_each() to list_for_each_entry() where applicable. This simplifies the code. Reported-by: Hulk Robot Signed-off-by: Wang Hai Signed-off-by: David S. Miller

net/x25: fix a mistake in grammar

2021-06-09T20:54:26Z

Fix a mistake in grammar. Signed-off-by: gushengxian Signed-off-by: David S. Miller

net: x25: Use list_for_each_entry() to simplify code in x25_forward.c

2021-06-08T23:31:25Z

Convert list_for_each() to list_for_each_entry() where applicable. This simplifies the code. Reported-by: Hulk Robot Signed-off-by: Wang Hai Signed-off-by: David S. Miller

net: x25: Use list_for_each_entry() to simplify code in x25_link.c

2021-06-08T23:31:24Z

Convert list_for_each() to list_for_each_entry() where applicable. This simplifies the code. Reported-by: Hulk Robot Signed-off-by: Wang Hai Signed-off-by: David S. Miller

net/x25: Return the correct errno code

2021-06-03T22:13:56Z

When kalloc or kmemdup failed, should return ENOMEM rather than ENOBUF. Signed-off-by: Zheng Yongjun Signed-off-by: David S. Miller