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Taehee Yoo cf7318b750 net: rmnet: fix lower interface leak
commit 2a762e9e8c upstream.

There are two types of the lower interface of rmnet that are VND
and BRIDGE.
Each lower interface can have only one type either VND or BRIDGE.
But, there is a case, which uses both lower interface types.
Due to this unexpected behavior, lower interface leak occurs.

Test commands:
    ip link add dummy0 type dummy
    ip link add dummy1 type dummy
    ip link add rmnet0 link dummy0 type rmnet mux_id 1
    ip link set dummy1 master rmnet0
    ip link add rmnet1 link dummy1 type rmnet mux_id 2
    ip link del rmnet0

The dummy1 was attached as BRIDGE interface of rmnet0.
Then, it also was attached as VND interface of rmnet1.
This is unexpected behavior and there is no code for handling this case.
So that below splat occurs when the rmnet0 interface is deleted.

Splat looks like:
[   53.254112][    C1] WARNING: CPU: 1 PID: 1192 at net/core/dev.c:8992 rollback_registered_many+0x986/0xcf0
[   53.254117][    C1] Modules linked in: rmnet dummy openvswitch nsh nf_conncount nf_nat nf_conntrack nf_defrag_ipv6 nfx
[   53.254182][    C1] CPU: 1 PID: 1192 Comm: ip Not tainted 5.8.0-rc1+ #620
[   53.254188][    C1] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[   53.254192][    C1] RIP: 0010:rollback_registered_many+0x986/0xcf0
[   53.254200][    C1] Code: 41 8b 4e cc 45 31 c0 31 d2 4c 89 ee 48 89 df e8 e0 47 ff ff 85 c0 0f 84 cd fc ff ff 0f 0b e5
[   53.254205][    C1] RSP: 0018:ffff888050a5f2e0 EFLAGS: 00010287
[   53.254214][    C1] RAX: ffff88805756d658 RBX: ffff88804d99c000 RCX: ffffffff8329d323
[   53.254219][    C1] RDX: 1ffffffff0be6410 RSI: 0000000000000008 RDI: ffffffff85f32080
[   53.254223][    C1] RBP: dffffc0000000000 R08: fffffbfff0be6411 R09: fffffbfff0be6411
[   53.254228][    C1] R10: ffffffff85f32087 R11: 0000000000000001 R12: ffff888050a5f480
[   53.254233][    C1] R13: ffff88804d99c0b8 R14: ffff888050a5f400 R15: ffff8880548ebe40
[   53.254238][    C1] FS:  00007f6b86b370c0(0000) GS:ffff88806c200000(0000) knlGS:0000000000000000
[   53.254243][    C1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[   53.254248][    C1] CR2: 0000562c62438758 CR3: 000000003f600005 CR4: 00000000000606e0
[   53.254253][    C1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[   53.254257][    C1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[   53.254261][    C1] Call Trace:
[   53.254266][    C1]  ? lockdep_hardirqs_on_prepare+0x379/0x540
[   53.254270][    C1]  ? netif_set_real_num_tx_queues+0x780/0x780
[   53.254275][    C1]  ? rmnet_unregister_real_device+0x56/0x90 [rmnet]
[   53.254279][    C1]  ? __kasan_slab_free+0x126/0x150
[   53.254283][    C1]  ? kfree+0xdc/0x320
[   53.254288][    C1]  ? rmnet_unregister_real_device+0x56/0x90 [rmnet]
[   53.254293][    C1]  unregister_netdevice_many.part.135+0x13/0x1b0
[   53.254297][    C1]  rtnl_delete_link+0xbc/0x100
[   53.254301][    C1]  ? rtnl_af_register+0xc0/0xc0
[   53.254305][    C1]  rtnl_dellink+0x2dc/0x840
[   53.254309][    C1]  ? find_held_lock+0x39/0x1d0
[   53.254314][    C1]  ? valid_fdb_dump_strict+0x620/0x620
[   53.254318][    C1]  ? rtnetlink_rcv_msg+0x457/0x890
[   53.254322][    C1]  ? lock_contended+0xd20/0xd20
[   53.254326][    C1]  rtnetlink_rcv_msg+0x4a8/0x890
[ ... ]
[   73.813696][ T1192] unregister_netdevice: waiting for rmnet0 to become free. Usage count = 1

Fixes: 037f9cdf72 ("net: rmnet: use upper/lower device infrastructure")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-07-22 09:31:58 +02:00
arch s390/mm: fix huge pte soft dirty copying 2020-07-16 08:17:28 +02:00
block block: release bip in a right way in error path 2020-07-16 08:17:23 +02:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto crypto: af_alg - fix use-after-free in af_alg_accept() due to bh_lock_sock() 2020-07-09 09:37:10 +02:00
Documentation mtd: rawnand: Pass a nand_chip object to nand_release() 2020-06-25 15:33:08 +02:00
drivers net: rmnet: fix lower interface leak 2020-07-22 09:31:58 +02:00
firmware Fix built-in early-load Intel microcode alignment 2020-01-23 08:21:29 +01:00
fs btrfs: fix fatal extent_buffer readahead vs releasepage race 2020-07-16 08:17:27 +02:00
include bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok() 2020-07-16 08:17:27 +02:00
init x86: Fix early boot crash on gcc-10, third try 2020-05-20 08:18:49 +02:00
ipc ipc/util.c: sysvipc_find_ipc() incorrectly updates position index 2020-05-20 08:18:40 +02:00
kernel bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok() 2020-07-16 08:17:27 +02:00
lib lib/zlib: remove outdated and incorrect pre-increment optimization 2020-06-25 15:33:02 +02:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm/slub: fix stack overruns with SLUB_STATS 2020-07-09 09:37:09 +02:00
net bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok() 2020-07-16 08:17:27 +02:00
samples samples: bpf: Fix build error 2020-06-03 08:19:31 +02:00
scripts kbuild: improve cc-option to clean up all temporary files 2020-06-30 23:17:15 -04:00
security apparmor: don't try to replace stale label in ptraceme check 2020-06-30 23:17:03 -04:00
sound ALSA: usb-audio: add quirk for MacroSilicon MS2109 2020-07-16 08:17:25 +02:00
tools perf: Make perf able to build with latest libbfd 2020-07-22 09:31:58 +02:00
usr initramfs: restore default compression behavior 2020-04-13 10:44:59 +02:00
virt KVM: arm64: Synchronize sysreg state on injecting an AArch32 exception 2020-06-22 09:05:09 +02:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Update drm/i915 bug filing URL 2020-02-28 16:38:49 +01:00
Makefile Linux 4.19.133 2020-07-16 08:17:28 +02:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

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

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