e252536068
In an IPvlan setup when master is set in loopback mode e.g.
ethtool -K eth0 set loopback on
where eth0 is master device for IPvlan setup.
The failure is caused by the faulty logic that determines if the
packet is from TX-path vs. RX-path by just looking at the mac-
addresses on the packet while processing multicast packets.
In the loopback-mode where this crash was happening, the packets
that are sent out are reflected by the NIC and are processed on
the RX path, but mac-address check tricks into thinking this
packet is from TX path and falsely uses dev_forward_skb() to pass
packets to the slave (virtual) devices.
This patch records the path while queueing packets and eliminates
logic of looking at mac-addresses for the same decision.
------------[ cut here ]------------
kernel BUG at include/linux/skbuff.h:1737!
Call Trace:
[<ffffffff921fbbc2>] dev_forward_skb+0x92/0xd0
[<ffffffffc031ac65>] ipvlan_process_multicast+0x395/0x4c0 [ipvlan]
[<ffffffffc031a9a7>] ? ipvlan_process_multicast+0xd7/0x4c0 [ipvlan]
[<ffffffff91cdfea7>] ? process_one_work+0x147/0x660
[<ffffffff91cdff09>] process_one_work+0x1a9/0x660
[<ffffffff91cdfea7>] ? process_one_work+0x147/0x660
[<ffffffff91ce086d>] worker_thread+0x11d/0x360
[<ffffffff91ce0750>] ? rescuer_thread+0x350/0x350
[<ffffffff91ce960b>] kthread+0xdb/0xe0
[<ffffffff91c05c70>] ? _raw_spin_unlock_irq+0x30/0x50
[<ffffffff91ce9530>] ? flush_kthread_worker+0xc0/0xc0
[<ffffffff92348b7a>] ret_from_fork+0x9a/0xd0
[<ffffffff91ce9530>] ? flush_kthread_worker+0xc0/0xc0
Fixes: ba35f8588f47 ("ipvlan: Defer multicast / broadcast processing to a work-queue")
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
CC: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.