linux/net/core/dev.c, branch v5.7

__netif_receive_skb_core: pass skb by reference

2020-05-19T22:38:00Z

__netif_receive_skb_core may change the skb pointer passed into it (e.g. in rx_handler). The original skb may be freed as a result of this operation. The callers of __netif_receive_skb_core may further process original skb by using pt_prev pointer returned by __netif_receive_skb_core thus leading to unpleasant effects. The solution is to pass skb by reference into __netif_receive_skb_core. v2: Added Fixes tag and comment regarding ppt_prev and skb invariant. Fixes: 88eb1944e18c ("net: core: propagate SKB lists through packet_type lookup") Signed-off-by: Boris Sukholitko Acked-by: Edward Cree Signed-off-by: David S. Miller

net: fix a potential recursive NETDEV_FEAT_CHANGE

2020-05-08T01:18:36Z

syzbot managed to trigger a recursive NETDEV_FEAT_CHANGE event between bonding master and slave. I managed to find a reproducer for this: ip li set bond0 up ifenslave bond0 eth0 brctl addbr br0 ethtool -K eth0 lro off brctl addif br0 bond0 ip li set br0 up When a NETDEV_FEAT_CHANGE event is triggered on a bonding slave, it captures this and calls bond_compute_features() to fixup its master's and other slaves' features. However, when syncing with its lower devices by netdev_sync_lower_features() this event is triggered again on slaves when the LRO feature fails to change, so it goes back and forth recursively until the kernel stack is exhausted. Commit 17b85d29e82c intentionally lets __netdev_update_features() return -1 for such a failure case, so we have to just rely on the existing check inside netdev_sync_lower_features() and skip NETDEV_FEAT_CHANGE event only for this specific failure case. Fixes: fd867d51f889 ("net/core: generic support for disabling netdev features down stack") Reported-by: syzbot+e73ceacfd8560cc8a3ca@syzkaller.appspotmail.com Reported-by: syzbot+c2fb6f9ddcea95ba49b5@syzkaller.appspotmail.com Cc: Jarod Wilson Cc: Nikolay Aleksandrov Cc: Josh Poimboeuf Cc: Jann Horn Reviewed-by: Jay Vosburgh Signed-off-by: Cong Wang Acked-by: Nikolay Aleksandrov Signed-off-by: David S. Miller

xdp: Reset prog in dev_change_xdp_fd when fd is negative

2020-04-14T19:38:02Z

The commit mentioned in the Fixes tag reuses the local prog variable when looking up an expected_fd. The variable is not reset when fd < 0 causing a detach with the expected_fd set to actually call dev_xdp_install for the existing program. The end result is that the detach does not happen. Fixes: 92234c8f15c8 ("xdp: Support specifying expected existing program when attaching XDP") Signed-off-by: David Ahern Signed-off-by: Daniel Borkmann Reviewed-by: Jakub Kicinski Reviewed-by: Toke Høiland-Jørgensen Link: https://lore.kernel.org/bpf/20200412133204.43847-1-dsahern@kernel.org

net: revert default NAPI poll timeout to 2 jiffies

2020-04-08T01:30:56Z

For HZ < 1000 timeout 2000us rounds up to 1 jiffy but expires randomly because next timer interrupt could come shortly after starting softirq. For commonly used CONFIG_HZ=1000 nothing changes. Fixes: 7acf8a1e8a28 ("Replace 2 jiffies with sysctl netdev_budget_usecs to enable softirq tuning") Reported-by: Dmitry Yakunin Signed-off-by: Konstantin Khlebnikov Signed-off-by: David S. Miller

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

2020-03-31T02:52:37Z

Signed-off-by: David S. Miller

net: Fix typo of SKB_SGO_CB_OFFSET

2020-03-30T04:53:18Z

The SKB_SGO_CB_OFFSET should be SKB_GSO_CB_OFFSET which means the offset of the GSO in skb cb. This patch fixes the typo. Fixes: 9207f9d45b0a ("net: preserve IP control block during GSO segmentation") Signed-off-by: Cambda Zhu Signed-off-by: David S. Miller

xdp: Support specifying expected existing program when attaching XDP

2020-03-28T21:24:41Z

While it is currently possible for userspace to specify that an existing XDP program should not be replaced when attaching to an interface, there is no mechanism to safely replace a specific XDP program with another. This patch adds a new netlink attribute, IFLA_XDP_EXPECTED_FD, which can be set along with IFLA_XDP_FD. If set, the kernel will check that the program currently loaded on the interface matches the expected one, and fail the operation if it does not. This corresponds to a 'cmpxchg' memory operation. Setting the new attribute with a negative value means that no program is expected to be attached, which corresponds to setting the UPDATE_IF_NOEXIST flag. A new companion flag, XDP_FLAGS_REPLACE, is also added to explicitly request checking of the EXPECTED_FD attribute. This is needed for userspace to discover whether the kernel supports the new attribute. Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Alexei Starovoitov Reviewed-by: Jakub Kicinski Link: https://lore.kernel.org/bpf/158515700640.92963.3551295145441017022.stgit@toke.dk

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2020-03-26T01:58:11Z

Overlapping header include additions in macsec.c A bug fix in 'net' overlapping with the removal of 'version' string in ena_netdev.c Overlapping test additions in selftests Makefile Overlapping PCI ID table adjustments in iwlwifi driver. Signed-off-by: David S. Miller

net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build

2020-03-25T19:24:33Z

net/netfilter/nft_fwd_netdev.c: In function ‘nft_fwd_netdev_eval’: net/netfilter/nft_fwd_netdev.c:32:10: error: ‘struct sk_buff’ has no member named ‘tc_redirected’ pkt->skb->tc_redirected = 1; ^~ net/netfilter/nft_fwd_netdev.c:33:10: error: ‘struct sk_buff’ has no member named ‘tc_from_ingress’ pkt->skb->tc_from_ingress = 1; ^~ To avoid a direct dependency with tc actions from netfilter, wrap the redirect bits around CONFIG_NET_REDIRECT and move helpers to include/linux/skbuff.h. Turn on this toggle from the ifb driver, the only existing client of these bits in the tree. This patch adds skb_set_redirected() that sets on the redirected bit on the skbuff, it specifies if the packet was redirect from ingress and resets the timestamp (timestamp reset was originally missing in the netfilter bugfix). Fixes: bcfabee1afd99484 ("netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress") Reported-by: noreply@ellerman.id.au Reported-by: Geert Uytterhoeven Signed-off-by: Pablo Neira Ayuso Signed-off-by: David S. Miller

netfilter: revert introduction of egress hook

2020-03-18T23:35:48Z

This reverts the following commits: 8537f78647c0 ("netfilter: Introduce egress hook") 5418d3881e1f ("netfilter: Generalize ingress hook") b030f194aed2 ("netfilter: Rename ingress hook include file") >From the discussion in [0], the author's main motivation to add a hook in fast path is for an out of tree kernel module, which is a red flag to begin with. Other mentioned potential use cases like NAT{64,46} is on future extensions w/o concrete code in the tree yet. Revert as suggested [1] given the weak justification to add more hooks to critical fast-path. [0] https://lore.kernel.org/netdev/cover.1583927267.git.lukas@wunner.de/ [1] https://lore.kernel.org/netdev/20200318.011152.72770718915606186.davem@davemloft.net/ Signed-off-by: Daniel Borkmann Cc: David Miller Cc: Pablo Neira Ayuso Cc: Alexei Starovoitov Nacked-by: Pablo Neira Ayuso Signed-off-by: David S. Miller