linux/include
Mahesh Bandewar 395eea6ccf rtnetlink: delay RTM_DELLINK notification until after ndo_uninit()
The commit 56bfa7ee7c ("unregister_netdevice : move RTM_DELLINK to
until after ndo_uninit") tried to do this ealier but while doing so
it created a problem. Unfortunately the delayed rtmsg_ifinfo() also
delayed call to fill_info(). So this translated into asking driver
to remove private state and then query it's private state. This
could have catastropic consequences.

This change breaks the rtmsg_ifinfo() into two parts - one takes the
precise snapshot of the device by called fill_info() before calling
the ndo_uninit() and the second part sends the notification using
collected snapshot.

It was brought to notice when last link is deleted from an ipvlan device
when it has free-ed the port and the subsequent .fill_info() call is
trying to get the info from the port.

kernel: [  255.139429] ------------[ cut here ]------------
kernel: [  255.139439] WARNING: CPU: 12 PID: 11173 at net/core/rtnetlink.c:2238 rtmsg_ifinfo+0x100/0x110()
kernel: [  255.139493] Modules linked in: ipvlan bonding w1_therm ds2482 wire cdc_acm ehci_pci ehci_hcd i2c_dev i2c_i801 i2c_core msr cpuid bnx2x ptp pps_core mdio libcrc32c
kernel: [  255.139513] CPU: 12 PID: 11173 Comm: ip Not tainted 3.18.0-smp-DEV #167
kernel: [  255.139514] Hardware name: Intel RML,PCH/Ibis_QC_18, BIOS 1.0.10 05/15/2012
kernel: [  255.139515]  0000000000000009 ffff880851b6b828 ffffffff815d87f4 00000000000000e0
kernel: [  255.139516]  0000000000000000 ffff880851b6b868 ffffffff8109c29c 0000000000000000
kernel: [  255.139518]  00000000ffffffa6 00000000000000d0 ffffffff81aaf580 0000000000000011
kernel: [  255.139520] Call Trace:
kernel: [  255.139527]  [<ffffffff815d87f4>] dump_stack+0x46/0x58
kernel: [  255.139531]  [<ffffffff8109c29c>] warn_slowpath_common+0x8c/0xc0
kernel: [  255.139540]  [<ffffffff8109c2ea>] warn_slowpath_null+0x1a/0x20
kernel: [  255.139544]  [<ffffffff8150d570>] rtmsg_ifinfo+0x100/0x110
kernel: [  255.139547]  [<ffffffff814f78b5>] rollback_registered_many+0x1d5/0x2d0
kernel: [  255.139549]  [<ffffffff814f79cf>] unregister_netdevice_many+0x1f/0xb0
kernel: [  255.139551]  [<ffffffff8150acab>] rtnl_dellink+0xbb/0x110
kernel: [  255.139553]  [<ffffffff8150da90>] rtnetlink_rcv_msg+0xa0/0x240
kernel: [  255.139557]  [<ffffffff81329283>] ? rhashtable_lookup_compare+0x43/0x80
kernel: [  255.139558]  [<ffffffff8150d9f0>] ? __rtnl_unlock+0x20/0x20
kernel: [  255.139562]  [<ffffffff8152cb11>] netlink_rcv_skb+0xb1/0xc0
kernel: [  255.139563]  [<ffffffff8150a495>] rtnetlink_rcv+0x25/0x40
kernel: [  255.139565]  [<ffffffff8152c398>] netlink_unicast+0x178/0x230
kernel: [  255.139567]  [<ffffffff8152c75f>] netlink_sendmsg+0x30f/0x420
kernel: [  255.139571]  [<ffffffff814e0b0c>] sock_sendmsg+0x9c/0xd0
kernel: [  255.139575]  [<ffffffff811d1d7f>] ? rw_copy_check_uvector+0x6f/0x130
kernel: [  255.139577]  [<ffffffff814e11c9>] ? copy_msghdr_from_user+0x139/0x1b0
kernel: [  255.139578]  [<ffffffff814e1774>] ___sys_sendmsg+0x304/0x310
kernel: [  255.139581]  [<ffffffff81198723>] ? handle_mm_fault+0xca3/0xde0
kernel: [  255.139585]  [<ffffffff811ebc4c>] ? destroy_inode+0x3c/0x70
kernel: [  255.139589]  [<ffffffff8108e6ec>] ? __do_page_fault+0x20c/0x500
kernel: [  255.139597]  [<ffffffff811e8336>] ? dput+0xb6/0x190
kernel: [  255.139606]  [<ffffffff811f05f6>] ? mntput+0x26/0x40
kernel: [  255.139611]  [<ffffffff811d2b94>] ? __fput+0x174/0x1e0
kernel: [  255.139613]  [<ffffffff814e2129>] __sys_sendmsg+0x49/0x90
kernel: [  255.139615]  [<ffffffff814e2182>] SyS_sendmsg+0x12/0x20
kernel: [  255.139617]  [<ffffffff815df092>] system_call_fastpath+0x12/0x17
kernel: [  255.139619] ---[ end trace 5e6703e87d984f6b ]---

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reported-by: Toshiaki Makita <makita.toshiaki@lab.ntt.co.jp>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: David S. Miller <davem@davemloft.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09 13:36:57 -05:00
..
acpi ACPI and power management updates for 3.18-rc2 2014-10-24 11:29:31 -07:00
asm-generic Revert "fast_hash: avoid indirect function calls" 2014-11-14 16:36:25 -05:00
clocksource
crypto crypto: LLVMLinux: Add macro to remove use of VLAIS in crypto code 2014-10-14 10:51:22 +02:00
drm drm/radeon: remove invalid pci id 2014-10-28 10:44:36 -04:00
dt-bindings The fixes for the clock framework are all regressions in drivers, plus a 2014-11-25 17:52:56 -08:00
keys KEYS: Restore partial ID matching functionality for asymmetric keys 2014-10-06 15:21:05 +01:00
kvm arm/arm64: KVM: Fix BE accesses to GICv2 EISR and ELRSR regs 2014-10-16 10:57:41 +02:00
linux rtnetlink: delay RTM_DELLINK notification until after ndo_uninit() 2014-12-09 13:36:57 -05:00
math-emu
media Merge branch 'patchwork' into v4l_for_linus 2014-10-09 14:00:54 -03:00
memory
misc cxl: Add new header for call backs and structs 2014-10-08 20:15:43 +11:00
net Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2014-12-08 21:30:21 -05:00
pcmcia
ras
rdma IB/mlx5, iser, isert: Add Signature API additions 2014-10-09 00:10:53 -07:00
rxrpc
scsi scsi: set REQ_QUEUE for the blk-mq case 2014-10-28 09:53:43 +01:00
soc/tegra
sound ALSA: pcm: Add big-endian DSD sample formats and fix XMOS DSD sample format 2014-11-21 15:13:28 +01:00
target target: Add force_pr_aptpl device attribute 2014-10-04 05:41:20 +00:00
trace Merge branch 'urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/urgent 2014-10-30 07:37:37 +01:00
uapi tc_act: export uapi header file 2014-12-09 13:34:10 -05:00
video fbdev changes for 3.18 2014-10-18 18:03:02 -07:00
xen xen: remove DEFINE_XENBUS_DRIVER() macro 2014-10-06 10:27:57 +01:00
Kbuild