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Eric Dumazet 3a415d59c1 net/sched: sch_taprio: fix possible use-after-free
syzbot reported a nasty crash [1] in net_tx_action() which
made little sense until we got a repro.

This repro installs a taprio qdisc, but providing an
invalid TCA_RATE attribute.

qdisc_create() has to destroy the just initialized
taprio qdisc, and taprio_destroy() is called.

However, the hrtimer used by taprio had already fired,
therefore advance_sched() called __netif_schedule().

Then net_tx_action was trying to use a destroyed qdisc.

We can not undo the __netif_schedule(), so we must wait
until one cpu serviced the qdisc before we can proceed.

Many thanks to Alexander Potapenko for his help.

[1]
BUG: KMSAN: uninit-value in queued_spin_trylock include/asm-generic/qspinlock.h:94 [inline]
BUG: KMSAN: uninit-value in do_raw_spin_trylock include/linux/spinlock.h:191 [inline]
BUG: KMSAN: uninit-value in __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline]
BUG: KMSAN: uninit-value in _raw_spin_trylock+0x92/0xa0 kernel/locking/spinlock.c:138
 queued_spin_trylock include/asm-generic/qspinlock.h:94 [inline]
 do_raw_spin_trylock include/linux/spinlock.h:191 [inline]
 __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline]
 _raw_spin_trylock+0x92/0xa0 kernel/locking/spinlock.c:138
 spin_trylock include/linux/spinlock.h:359 [inline]
 qdisc_run_begin include/net/sch_generic.h:187 [inline]
 qdisc_run+0xee/0x540 include/net/pkt_sched.h:125
 net_tx_action+0x77c/0x9a0 net/core/dev.c:5086
 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571
 run_ksoftirqd+0x2c/0x50 kernel/softirq.c:934
 smpboot_thread_fn+0x554/0x9f0 kernel/smpboot.c:164
 kthread+0x31b/0x430 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970
 kmalloc_reserve net/core/skbuff.c:358 [inline]
 __alloc_skb+0x346/0xcf0 net/core/skbuff.c:430
 alloc_skb include/linux/skbuff.h:1257 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 netlink_ack+0x5f3/0x12b0 net/netlink/af_netlink.c:2436
 netlink_rcv_skb+0x55d/0x6c0 net/netlink/af_netlink.c:2507
 rtnetlink_rcv+0x30/0x40 net/core/rtnetlink.c:6108
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg net/socket.c:2565 [inline]
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __x64_sys_sendmsg+0x367/0x540 net/socket.c:2572
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 6.0.0-rc2-syzkaller-47461-gac3859c02d7f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022

Fixes: 5a781ccbd1 ("tc: Add support for configuring the taprio scheduler")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-01-16 13:25:34 +00:00
arch s390 updates for 6.2-rc4 2023-01-12 17:09:20 -06:00
block block-2023-01-06 2023-01-06 13:12:42 -08:00
certs certs: make system keyring depend on built-in x509 parser 2022-09-24 04:31:18 +09:00
crypto This update includes the following changes: 2022-12-14 12:31:09 -08:00
Documentation Including fixes from rxrpc. 2023-01-12 18:20:44 -06:00
drivers net: stmmac: Fix queue statistics reading 2023-01-16 13:10:04 +00:00
fs Including fixes from rxrpc. 2023-01-12 18:20:44 -06:00
include net/sched: sch_taprio: fix possible use-after-free 2023-01-16 13:25:34 +00:00
init gcc: disable -Warray-bounds for gcc-11 too 2023-01-09 17:04:49 -06:00
io_uring io_uring: fix CQ waiting timeout handling 2023-01-05 08:04:47 -07:00
ipc Non-MM patches for 6.2-rc1. 2022-12-12 17:28:58 -08:00
kernel - Fix various DocBook formatting errors in kernel/time/ that 2023-01-12 16:53:39 -06:00
lib v6.2 first rc pull request 2023-01-07 10:06:47 -08:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm memblock: Fix doc for memblock_phys_free 2023-01-04 12:31:22 +02:00
net net/sched: sch_taprio: fix possible use-after-free 2023-01-16 13:25:34 +00:00
rust rust: types: add Opaque type 2022-12-04 01:59:16 +01:00
samples Char/Misc driver changes for 6.2-rc1 2022-12-16 03:49:24 -08:00
scripts kbuild: readd -w option when vmlinux.o or Module.symver is missing 2023-01-05 16:53:48 +09:00
security kernel hardening fixes for v6.2-rc1 2022-12-23 12:00:24 -08:00
sound xen: branch for v6.2-rc4 2023-01-12 17:02:20 -06:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf 2023-01-16 13:10:16 +00:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt Merge branch 'kvm-late-6.1-fixes' into HEAD 2022-12-28 07:19:14 -05:00
.clang-format iommufd for 6.2 2022-12-14 09:15:43 -08:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: use 'dts' diff driver for dts files 2019-12-04 19:44:11 -08:00
.gitignore .gitignore: ignore *.rpm 2022-12-30 17:22:14 +09:00
.mailmap MAINTAINERS: Update email of Tudor Ambarus 2023-01-07 15:18:44 +01:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: zram: zsmalloc: Add an additional co-maintainer 2022-12-15 16:37:49 -08:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS MTD changes: 2023-01-12 05:56:06 -06:00
Makefile Linux 6.2-rc3 2023-01-08 11:49:43 -06:00
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.