linux.git/drivers/net/tun.c, branch v5.12

net: tun: set tun->dev->addr_len during TUNSETLINK processing

2021-04-06T23:52:21+00:00

When changing type with TUNSETLINK ioctl command, set tun->dev->addr_len
to match the appropriate type, using new tun_get_addr_len utility function
which returns appropriate address length for given type. Fixes a
KMSAN-found uninit-value bug reported by syzbot at:
https://syzkaller.appspot.com/bug?id=0766d38c656abeace60621896d705743aeefed51

Reported-by: syzbot+001516d86dbe88862cec@syzkaller.appspotmail.com
Diagnosed-by: Eric Dumazet 
Signed-off-by: Phillip Potter 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller

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: tun: fix misspellings using codespell tool

2021-01-20T01:43:56+00:00

Some typos are found out by codespell tool:

$ codespell -w -i 3 ./drivers/net/tun.c
aovid  ==> avoid

Fix typos found by codespell.

Signed-off-by: Menglong Dong 
Link: https://lore.kernel.org/r/20210118111539.35886-1-dong.menglong@zte.com.cn
Signed-off-by: Jakub Kicinski

net, xdp: Introduce xdp_prepare_buff utility routine

2021-01-08T21:39:24+00:00

Introduce xdp_prepare_buff utility routine to initialize per-descriptor
xdp_buff fields (e.g. xdp_buff pointers). Rely on xdp_prepare_buff() in
all XDP capable drivers.

Signed-off-by: Lorenzo Bianconi 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Alexander Duyck 
Acked-by: Jesper Dangaard Brouer 
Acked-by: John Fastabend 
Acked-by: Shay Agroskin 
Acked-by: Martin Habets 
Acked-by: Camelia Groza 
Acked-by: Marcin Wojtas 
Link: https://lore.kernel.org/bpf/45f46f12295972a97da8ca01990b3e71501e9d89.1608670965.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov

net, xdp: Introduce xdp_init_buff utility routine

2021-01-08T21:39:24+00:00

Introduce xdp_init_buff utility routine to initialize xdp_buff fields
const over NAPI iterations (e.g. frame_sz or rxq pointer). Rely on
xdp_init_buff in all XDP capable drivers.

Signed-off-by: Lorenzo Bianconi 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Alexander Duyck 
Acked-by: Jesper Dangaard Brouer 
Acked-by: John Fastabend 
Acked-by: Shay Agroskin 
Acked-by: Martin Habets 
Acked-by: Camelia Groza 
Acked-by: Marcin Wojtas 
Link: https://lore.kernel.org/bpf/7f8329b6da1434dc2b05a77f2e800b29628a8913.1608670965.git.lorenzo@kernel.org
Signed-off-by: Alexei Starovoitov

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

tun: fix return value when the number of iovs exceeds MAX_SKB_FRAGS

2020-12-28T21:34:36+00:00

Currently the tun_napi_alloc_frags() function returns -ENOMEM when the
number of iovs exceeds MAX_SKB_FRAGS + 1. However this is inappropriate,
we should use -EMSGSIZE instead of -ENOMEM.

The following distinctions are matters:
1. the caller need to drop the bad packet when -EMSGSIZE is returned,
   which means meeting a persistent failure.
2. the caller can try again when -ENOMEM is returned, which means
   meeting a transient failure.

Fixes: 90e33d459407 ("tun: enable napi_gro_frags() for TUN/TAP driver")
Signed-off-by: Yunjian Wang 
Acked-by: Willem de Bruijn 
Acked-by: Jason Wang 
Acked-by: Michael S. Tsirkin 
Link: https://lore.kernel.org/r/1608864736-24332-1-git-send-email-wangyunjian@huawei.com
Signed-off-by: Jakub Kicinski

Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

2020-12-04T15:48:12+00:00

Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-12-03

The main changes are:

1) Support BTF in kernel modules, from Andrii.

2) Introduce preferred busy-polling, from Björn.

3) bpf_ima_inode_hash() and bpf_bprm_opts_set() helpers, from KP Singh.

4) Memcg-based memory accounting for bpf objects, from Roman.

5) Allow bpf_{s,g}etsockopt from cgroup bind{4,6} hooks, from Stanislav.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (118 commits)
  selftests/bpf: Fix invalid use of strncat in test_sockmap
  libbpf: Use memcpy instead of strncpy to please GCC
  selftests/bpf: Add fentry/fexit/fmod_ret selftest for kernel module
  selftests/bpf: Add tp_btf CO-RE reloc test for modules
  libbpf: Support attachment of BPF tracing programs to kernel modules
  libbpf: Factor out low-level BPF program loading helper
  bpf: Allow to specify kernel module BTFs when attaching BPF programs
  bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier
  selftests/bpf: Add CO-RE relocs selftest relying on kernel module BTF
  selftests/bpf: Add support for marking sub-tests as skipped
  selftests/bpf: Add bpf_testmod kernel module for testing
  libbpf: Add kernel module BTF support for CO-RE relocations
  libbpf: Refactor CO-RE relocs to not assume a single BTF object
  libbpf: Add internal helper to load BTF data by FD
  bpf: Keep module's btf_data_size intact after load
  bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address()
  selftests/bpf: Add Userspace tests for TCP_WINDOW_CLAMP
  bpf: Adds support for setting window clamp
  samples/bpf: Fix spelling mistake "recieving" -> "receiving"
  bpf: Fix cold build of test_progs-no_alu32
  ...
====================

Link: https://lore.kernel.org/r/20201204021936.85653-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski