lwn.git/net/can/raw.c, branch v4.13-rc3

can: initial support for network namespaces

2017-04-04T15:35:58+00:00

This patch adds initial support for network namespaces. The changes only enable support in the CAN raw, proc and af_can code. GW and BCM still have their checks that ensure that they are used only from the main namespace. The patch boils down to moving the global structures, i.e. the global filter list and their /proc stats, into a per-namespace structure and passing around the corresponding "struct net" in a lot of different places. Changes since v1: - rebased on current HEAD (2bfe01e) - fixed overlong line Signed-off-by: Mario Kicherer Signed-off-by: Marc Kleine-Budde

can: Fix kernel panic at security_sock_rcv_skb

2017-01-29T23:30:56+00:00

Zhang Yanmin reported crashes [1] and provided a patch adding a synchronize_rcu() call in can_rx_unregister() The main problem seems that the sockets themselves are not RCU protected. If CAN uses RCU for delivery, then sockets should be freed only after one RCU grace period. Recent kernels could use sock_set_flag(sk, SOCK_RCU_FREE), but let's ease stable backports with the following fix instead. [1] BUG: unable to handle kernel NULL pointer dereference at (null) IP: [] selinux_socket_sock_rcv_skb+0x65/0x2a0 Call Trace: [] security_sock_rcv_skb+0x4c/0x60 [] sk_filter+0x41/0x210 [] sock_queue_rcv_skb+0x53/0x3a0 [] raw_rcv+0x2a3/0x3c0 [] can_rcv_filter+0x12b/0x370 [] can_receive+0xd9/0x120 [] can_rcv+0xab/0x100 [] __netif_receive_skb_core+0xd8c/0x11f0 [] __netif_receive_skb+0x24/0xb0 [] process_backlog+0x127/0x280 [] net_rx_action+0x33b/0x4f0 [] __do_softirq+0x184/0x440 [] do_softirq_own_stack+0x1c/0x30 [] do_softirq.part.18+0x3b/0x40 [] do_softirq+0x1d/0x20 [] netif_rx_ni+0xe5/0x110 [] slcan_receive_buf+0x507/0x520 [] flush_to_ldisc+0x21c/0x230 [] process_one_work+0x24f/0x670 [] worker_thread+0x9d/0x6f0 [] ? rescuer_thread+0x480/0x480 [] kthread+0x12c/0x150 [] ret_from_fork+0x3f/0x70 Reported-by: Zhang Yanmin Signed-off-by: Eric Dumazet Acked-by: Oliver Hartkopp Signed-off-by: David S. Miller

can: raw: raw_setsockopt: limit number of can_filter that can be set

2016-12-07T09:45:57+00:00

This patch adds a check to limit the number of can_filters that can be set via setsockopt on CAN_RAW sockets. Otherwise allocations > MAX_ORDER are not prevented resulting in a warning. Reference: https://lkml.org/lkml/2016/12/2/230 Reported-by: Andrey Konovalov Tested-by: Andrey Konovalov Cc: linux-stable Signed-off-by: Marc Kleine-Budde

sock: enable timestamping using control messages

2016-04-04T19:50:30+00:00

Currently, SOL_TIMESTAMPING can only be enabled using setsockopt. This is very costly when users want to sample writes to gather tx timestamps. Add support for enabling SO_TIMESTAMPING via control messages by using tsflags added in `struct sockcm_cookie` (added in the previous patches in this series) to set the tx_flags of the last skb created in a sendmsg. With this patch, the timestamp recording bits in tx_flags of the skbuff is overridden if SO_TIMESTAMPING is passed in a cmsg. Please note that this is only effective for overriding the recording timestamps flags. Users should enable timestamp reporting (e.g., SOF_TIMESTAMPING_SOFTWARE | SOF_TIMESTAMPING_OPT_ID) using socket options and then should ask for SOF_TIMESTAMPING_TX_* using control messages per sendmsg to sample timestamps for each write. Signed-off-by: Soheil Hassas Yeganeh Acked-by: Willem de Bruijn Signed-off-by: David S. Miller

can: replace timestamp as unique skb attribute

2015-07-12T19:13:22+00:00

Commit 514ac99c64b "can: fix multiple delivery of a single CAN frame for overlapping CAN filters" requires the skb->tstamp to be set to check for identical CAN skbs. Without timestamping to be required by user space applications this timestamp was not generated which lead to commit 36c01245eb8 "can: fix loss of CAN frames in raw_rcv" - which forces the timestamp to be set in all CAN related skbuffs by introducing several __net_timestamp() calls. This forces e.g. out of tree drivers which are not using alloc_can{,fd}_skb() to add __net_timestamp() after skbuff creation to prevent the frame loss fixed in mainline Linux. This patch removes the timestamp dependency and uses an atomic counter to create an unique identifier together with the skbuff pointer. Btw: the new skbcnt element introduced in struct can_skb_priv has to be initialized with zero in out-of-tree drivers which are not using alloc_can{,fd}_skb() too. Signed-off-by: Oliver Hartkopp Cc: linux-stable Signed-off-by: Marc Kleine-Budde

can: introduce new raw socket option to join the given CAN filters

2015-04-01T09:28:22+00:00

The CAN_RAW socket can set multiple CAN identifier specific filters that lead to multiple filters in the af_can.c filter processing. These filters are indenpendent from each other which leads to logical OR'ed filters when applied. This socket option joines the given CAN filters in the way that only CAN frames are passed to user space that matched *all* given CAN filters. The semantic for the applied filters is therefore changed to a logical AND. This is useful especially when the filterset is a combination of filters where the CAN_INV_FILTER flag is set in order to notch single CAN IDs or CAN ID ranges from the incoming traffic. As the raw_rcv() function is executed from NET_RX softirq the introduced variables are implemented as per-CPU variables to avoid extensive locking at CAN frame reception time. Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde

can: fix multiple delivery of a single CAN frame for overlapping CAN filters

2015-04-01T09:27:41+00:00

The CAN_RAW socket can set multiple CAN identifier specific filters that lead to multiple filters in the af_can.c filter processing. These filters are indenpendent from each other which leads to logical OR'ed filters when applied. This patch makes sure that every CAN frame which is filtered for a specific socket is only delivered once to the user space. This is independent from the number of matching CAN filters of this socket. As the raw_rcv() function is executed from NET_RX softirq the introduced variables are implemented as per-CPU variables to avoid extensive locking at CAN frame reception time. Signed-off-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde

net: Remove iocb argument from sendmsg and recvmsg

2015-03-02T18:06:31+00:00

After TIPC doesn't depend on iocb argument in its internal implementations of sendmsg() and recvmsg() hooks defined in proto structure, no any user is using iocb argument in them at all now. Then we can drop the redundant iocb argument completely from kinds of implementations of both sendmsg() and recvmsg() in the entire networking stack. Cc: Christoph Hellwig Suggested-by: Al Viro Signed-off-by: Ying Xue Signed-off-by: David S. Miller

net: use common macro for assering skb->cb[] available size in protocol families

2015-03-02T05:19:30+00:00

As part of an effort to move skb->dropcount to skb->cb[] use a common macro in protocol families using skb->cb[] for ancillary data to validate available room in skb->cb[]. Signed-off-by: Eyal Birger Signed-off-by: David S. Miller

can: eliminate banner[] variable and switch to pr_info()

2014-12-07T20:22:01+00:00

Several CAN modules use a design pattern with a banner[] variable at the top which defines a string that is used once during init to print the banner. The string is also embedded with KERN_INFO which makes it printk() specific. Improve the code by eliminating the banner[] variable and moving the string to where it is printed. Then switch from printk(KERN_INFO to pr_info() for the lines that were changed. Signed-off-by: Jeremiah Mahler Acked-by: Oliver Hartkopp Signed-off-by: Marc Kleine-Budde