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Eric Dumazet 2a5ff07a0e gro_cells: make sure device is up in gro_cells_receive()
We keep receiving syzbot reports [1] that show that tunnels do not play
the rcu/IFF_UP rules properly.

At device dismantle phase, gro_cells_destroy() will be called
only after a full rcu grace period is observed after IFF_UP
has been cleared.

This means that IFF_UP needs to be tested before queueing packets
into netif_rx() or gro_cells.

This patch implements the test in gro_cells_receive() because
too many callers do not seem to bother enough.

[1]
BUG: unable to handle kernel paging request at fffff4ca0b9ffffe
PGD 0 P4D 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.0.0+ #97
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: netns cleanup_net
RIP: 0010:__skb_unlink include/linux/skbuff.h:1929 [inline]
RIP: 0010:__skb_dequeue include/linux/skbuff.h:1945 [inline]
RIP: 0010:__skb_queue_purge include/linux/skbuff.h:2656 [inline]
RIP: 0010:gro_cells_destroy net/core/gro_cells.c:89 [inline]
RIP: 0010:gro_cells_destroy+0x19d/0x360 net/core/gro_cells.c:78
Code: 03 42 80 3c 20 00 0f 85 53 01 00 00 48 8d 7a 08 49 8b 47 08 49 c7 07 00 00 00 00 48 89 f9 49 c7 47 08 00 00 00 00 48 c1 e9 03 <42> 80 3c 21 00 0f 85 10 01 00 00 48 89 c1 48 89 42 08 48 c1 e9 03
RSP: 0018:ffff8880aa3f79a8 EFLAGS: 00010a02
RAX: 00ffffffffffffe8 RBX: ffffe8ffffc64b70 RCX: 1ffff8ca0b9ffffe
RDX: ffffc6505cffffe8 RSI: ffffffff858410ca RDI: ffffc6505cfffff0
RBP: ffff8880aa3f7a08 R08: ffff8880aa3e8580 R09: fffffbfff1263645
R10: fffffbfff1263644 R11: ffffffff8931b223 R12: dffffc0000000000
R13: 0000000000000000 R14: ffffe8ffffc64b80 R15: ffffe8ffffc64b75
kobject: 'loop2' (000000004bd7d84a): kobject_uevent_env
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff4ca0b9ffffe CR3: 0000000094941000 CR4: 00000000001406f0
Call Trace:
kobject: 'loop2' (000000004bd7d84a): fill_kobj_path: path = '/devices/virtual/block/loop2'
 ip_tunnel_dev_free+0x19/0x60 net/ipv4/ip_tunnel.c:1010
 netdev_run_todo+0x51c/0x7d0 net/core/dev.c:8970
 rtnl_unlock+0xe/0x10 net/core/rtnetlink.c:116
 ip_tunnel_delete_nets+0x423/0x5f0 net/ipv4/ip_tunnel.c:1124
 vti_exit_batch_net+0x23/0x30 net/ipv4/ip_vti.c:495
 ops_exit_list.isra.0+0x105/0x160 net/core/net_namespace.c:156
 cleanup_net+0x3fb/0x960 net/core/net_namespace.c:551
 process_one_work+0x98e/0x1790 kernel/workqueue.c:2173
 worker_thread+0x98/0xe40 kernel/workqueue.c:2319
 kthread+0x357/0x430 kernel/kthread.c:246
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
CR2: fffff4ca0b9ffffe
   [ end trace 513fc9c1338d1cb3 ]
RIP: 0010:__skb_unlink include/linux/skbuff.h:1929 [inline]
RIP: 0010:__skb_dequeue include/linux/skbuff.h:1945 [inline]
RIP: 0010:__skb_queue_purge include/linux/skbuff.h:2656 [inline]
RIP: 0010:gro_cells_destroy net/core/gro_cells.c:89 [inline]
RIP: 0010:gro_cells_destroy+0x19d/0x360 net/core/gro_cells.c:78
Code: 03 42 80 3c 20 00 0f 85 53 01 00 00 48 8d 7a 08 49 8b 47 08 49 c7 07 00 00 00 00 48 89 f9 49 c7 47 08 00 00 00 00 48 c1 e9 03 <42> 80 3c 21 00 0f 85 10 01 00 00 48 89 c1 48 89 42 08 48 c1 e9 03
RSP: 0018:ffff8880aa3f79a8 EFLAGS: 00010a02
RAX: 00ffffffffffffe8 RBX: ffffe8ffffc64b70 RCX: 1ffff8ca0b9ffffe
RDX: ffffc6505cffffe8 RSI: ffffffff858410ca RDI: ffffc6505cfffff0
RBP: ffff8880aa3f7a08 R08: ffff8880aa3e8580 R09: fffffbfff1263645
R10: fffffbfff1263644 R11: ffffffff8931b223 R12: dffffc0000000000
kobject: 'loop3' (00000000e4ee57a6): kobject_uevent_env
R13: 0000000000000000 R14: ffffe8ffffc64b80 R15: ffffe8ffffc64b75
FS:  0000000000000000(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: fffff4ca0b9ffffe CR3: 0000000094941000 CR4: 00000000001406f0

Fixes: c9e6bc644e ("net: add gro_cells infrastructure")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-10 11:07:14 -07:00
arch ARM: dts: stm32: Add Ethernet support on stm32h7 SOC and activate it for eval and disco boards 2019-03-08 11:48:19 -08:00
block for-linus-20190215 2019-02-15 09:12:28 -08:00
certs kbuild: remove redundant target cleaning on failure 2019-01-06 09:46:51 +09:00
crypto Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-03-05 09:09:55 -08:00
Documentation dt-bindings: net: stmmac: remove syscfg clock property 2019-03-08 11:48:19 -08:00
drivers vxlan: test dev->flags & IFF_UP before calling gro_cells_receive() 2019-03-10 11:05:52 -07:00
firmware kbuild: change filechk to surround the given command with { } 2019-01-06 09:46:51 +09:00
fs a.out: remove core dumping support 2019-03-05 10:00:35 -08:00
include ip: fix ip_mc_may_pull() return value 2019-03-09 19:52:47 -08:00
init revert "initramfs: cleanup incomplete rootfs" 2019-02-21 09:00:59 -08:00
ipc ipc: introduce ksys_ipc()/compat_ksys_ipc() for s390 2019-01-18 09:33:18 +01:00
kernel bpf: fix replace_map_fd_with_map_ptr's ldimm64 second imm field 2019-03-07 08:47:13 -08:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-03-04 13:26:15 -08:00
LICENSES This is a fairly typical cycle for documentation. There's some welcome 2018-10-24 18:01:11 +01:00
mm Merge branch 'akpm' (patches from Andrew) 2019-03-01 09:04:59 -08:00
net gro_cells: make sure device is up in gro_cells_receive() 2019-03-10 11:07:14 -07:00
samples bpf: hbm: fix spelling mistake "deault" -> "default" 2019-03-07 10:35:00 +01:00
scripts kasan: turn off asan-stack for clang-8 and earlier 2019-03-01 09:02:33 -08:00
security get rid of legacy 'get_ds()' function 2019-03-04 10:50:14 -08:00
sound sound fixes for 5.0 2019-02-20 09:42:52 -08:00
tools bpf, libbpf: fixing leak when kernel does not support btf 2019-03-08 21:16:36 +01:00
usr user/Makefile: Fix typo and capitalization in comment section 2018-12-11 00:18:03 +09:00
virt kvm: properly check debugfs dentry before using it 2019-02-28 08:57:32 -08:00
.clang-format clang-format: Update .clang-format with the latest for_each macro list 2019-01-19 19:26:06 +01:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore kbuild: Add support for DT binding schema checks 2018-12-13 09:41:32 -06:00
.mailmap .mailmap: Add Mathieu Othacehe 2019-02-21 11:41:19 +00:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS CREDITS/MAINTAINERS: Retire parisc-linux.org email domain 2019-02-21 20:16:10 +01:00
Kbuild kbuild: use assignment instead of define ... endef for filechk_* rules 2019-01-06 10:22:35 +09:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS appletalk: Add atalk.h header files to MAINTAINERS file 2019-03-06 10:46:43 -08:00
Makefile Linux 5.0 2019-03-03 15:21:29 -08:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

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.