kernel/linux.git/drivers/net/tap.c, branch v5.19

net: tap: track dropped skb via kfree_skb_reason()

2022-03-06T11:04:01+00:00

The TAP can be used as vhost-net backend. E.g., the tap_handle_frame() is the interface to forward the skb from TAP to vhost-net/virtio-net. However, there are many "goto drop" in the TAP driver. Therefore, the kfree_skb_reason() is involved at each "goto drop" to help userspace ftrace/ebpf to track the reason for the loss of packets. The below reasons are introduced: - SKB_DROP_REASON_SKB_CSUM - SKB_DROP_REASON_SKB_GSO_SEG - SKB_DROP_REASON_SKB_UCOPY_FAULT - SKB_DROP_REASON_DEV_HDR - SKB_DROP_REASON_FULL_RING Cc: Joao Martins Cc: Joe Jin Signed-off-by: Dongli Zhang Signed-off-by: David S. Miller

tuntap: add sanity checks about msg_controllen in sendmsg

2022-03-03T06:00:59+00:00

In patch [1], tun_msg_ctl was added to allow pass batched xdp buffers to tun_sendmsg. Although we donot use msg_controllen in this path, we should check msg_controllen to make sure the caller pass a valid msg_ctl. [1]: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=fe8dd45bb7556246c6b76277b1ba4296c91c2505 Reported-by: Eric Dumazet Suggested-by: Jason Wang Signed-off-by: Harold Huang Acked-by: Jason Wang Link: https://lore.kernel.org/r/20220303022441.383865-1-baymaxhuang@gmail.com Signed-off-by: Jakub Kicinski

net: fix dev_ifsioc_locked() race condition

2021-02-12T02:14:19+00:00

dev_ifsioc_locked() is called with only RCU read lock, so when there is a parallel writer changing the mac address, it could get a partially updated mac address, as shown below: Thread 1 Thread 2 // eth_commit_mac_addr_change() memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); // dev_ifsioc_locked() memcpy(ifr->ifr_hwaddr.sa_data, dev->dev_addr,...); Close this race condition by guarding them with a RW semaphore, like netdev_get_name(). We can not use seqlock here as it does not allow blocking. The writers already take RTNL anyway, so this does not affect the slow path. To avoid bothering existing dev_set_mac_address() callers in drivers, introduce a new wrapper just for user-facing callers on ioctl and rtnetlink paths. Note, bonding also changes slave mac addresses but that requires a separate patch due to the complexity of bonding code. Fixes: 3710becf8a58 ("net: RCU locking for simple ioctl()") Reported-by: "Gong, Sishuai" Cc: Eric Dumazet Cc: Jakub Kicinski Signed-off-by: Cong Wang Signed-off-by: David S. Miller

net: tap: check vlan with eth_type_vlan() method

2021-01-16T04:13:49+00:00

Replace some checks for ETH_P_8021Q and ETH_P_8021AD in drivers/net/tap.c with eth_type_vlan. Signed-off-by: Menglong Dong Link: https://lore.kernel.org/r/20210115023238.4681-1-dong.menglong@zte.com.cn Signed-off-by: Jakub Kicinski

tap/tun: add skb_zcopy_init() helper for initialization.

2021-01-08T00:08:37+00:00

Replace direct assignments with skb_zcopy_init() for zerocopy cases where a new skb is initialized, without changing the reference counts. Signed-off-by: Jonathan Lemon Signed-off-by: Jakub Kicinski

net: group skb_shinfo zerocopy related bits together.

2021-01-08T00:08:37+00:00

In preparation for expanded zerocopy (TX and RX), move the zerocopy related bits out of tx_flags into their own flag word. Signed-off-by: Jonathan Lemon Signed-off-by: Jakub Kicinski

skbuff: Add skb parameter to the ubuf zerocopy callback

2021-01-08T00:06:37+00:00

Add an optional skb parameter to the zerocopy callback parameter, which is passed down from skb_zcopy_clear(). This gives access to the original skb, which is needed for upcoming RX zero-copy error handling. Signed-off-by: Jonathan Lemon Signed-off-by: Jakub Kicinski

net: tap: use skb_list_walk_safe helper for gso segments

2020-01-08T23:19:55+00:00

This is a straight-forward conversion case for the new function, and while we're at it, we can remove a null write to skb->next by replacing it with skb_mark_not_on_list. Signed-off-by: Jason A. Donenfeld Signed-off-by: David S. Miller

compat_ioctl: move drivers to compat_ptr_ioctl

2019-10-23T15:23:43+00:00

Each of these drivers has a copy of the same trivial helper function to convert the pointer argument and then call the native ioctl handler. We now have a generic implementation of that, so use it. Acked-by: Greg Kroah-Hartman Acked-by: Michael S. Tsirkin Acked-by: David S. Miller Acked-by: Jarkko Sakkinen Reviewed-by: Jarkko Sakkinen Reviewed-by: Jason Gunthorpe Reviewed-by: Jiri Kosina Reviewed-by: Stefan Hajnoczi Reviewed-by: Cornelia Huck Signed-off-by: Arnd Bergmann

net: tap: clean up an indentation issue

2019-09-27T18:58:35+00:00

There is a statement that is indented too deeply, remove the extraneous tab. Signed-off-by: Colin Ian King Signed-off-by: David S. Miller