linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	stable@vger.kernel.org, Eric Dumazet <edumazet@google.com>,
	syzbot <syzkaller@googlegroups.com>,
	Jakub Kicinski <kuba@kernel.org>, Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.9 10/25] net_sched: fix NULL deref in fifo_set_limit()
Date: Thu, 14 Oct 2021 16:53:41 +0200	[thread overview]
Message-ID: <20211014145207.901653380@linuxfoundation.org> (raw)
In-Reply-To: <20211014145207.575041491@linuxfoundation.org>

From: Eric Dumazet <edumazet@google.com>

[ Upstream commit 560ee196fe9e5037e5015e2cdb14b3aecb1cd7dc ]

syzbot reported another NULL deref in fifo_set_limit() [1]

I could repro the issue with :

unshare -n
tc qd add dev lo root handle 1:0 tbf limit 200000 burst 70000 rate 100Mbit
tc qd replace dev lo parent 1:0 pfifo_fast
tc qd change dev lo root handle 1:0 tbf limit 300000 burst 70000 rate 100Mbit

pfifo_fast does not have a change() operation.
Make fifo_set_limit() more robust about this.

[1]
BUG: kernel NULL pointer dereference, address: 0000000000000000
PGD 1cf99067 P4D 1cf99067 PUD 7ca49067 PMD 0
Oops: 0010 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 14443 Comm: syz-executor959 Not tainted 5.15.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:0x0
Code: Unable to access opcode bytes at RIP 0xffffffffffffffd6.
RSP: 0018:ffffc9000e2f7310 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffffffff8d6ecc00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffff888024c27910 RDI: ffff888071e34000
RBP: ffff888071e34000 R08: 0000000000000001 R09: ffffffff8fcfb947
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888024c27910
R13: ffff888071e34018 R14: 0000000000000000 R15: ffff88801ef74800
FS:  00007f321d897700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 00000000722c3000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 fifo_set_limit net/sched/sch_fifo.c:242 [inline]
 fifo_set_limit+0x198/0x210 net/sched/sch_fifo.c:227
 tbf_change+0x6ec/0x16d0 net/sched/sch_tbf.c:418
 qdisc_change net/sched/sch_api.c:1332 [inline]
 tc_modify_qdisc+0xd9a/0x1a60 net/sched/sch_api.c:1634
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5572
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: fb0305ce1b03 ("net-sched: consolidate default fifo qdisc setup")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20210930212239.3430364-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/sched/sch_fifo.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/net/sched/sch_fifo.c b/net/sched/sch_fifo.c
index 1e37247656f8..8b7110cbcce4 100644
--- a/net/sched/sch_fifo.c
+++ b/net/sched/sch_fifo.c
@@ -151,6 +151,9 @@ int fifo_set_limit(struct Qdisc *q, unsigned int limit)
 	if (strncmp(q->ops->id + 1, "fifo", 4) != 0)
 		return 0;
 
+	if (!q->ops->change)
+		return 0;
+
 	nla = kmalloc(nla_attr_size(sizeof(struct tc_fifo_qopt)), GFP_KERNEL);
 	if (nla) {
 		nla->nla_type = RTM_NEWQDISC;
-- 
2.33.0




  parent reply	other threads:[~2021-10-14 14:56 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-14 14:53 [PATCH 4.9 00/25] 4.9.287-rc1 review Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 01/25] Partially revert "usb: Kconfig: using select for USB_COMMON dependency" Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 02/25] USB: cdc-acm: fix racy tty buffer accesses Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 03/25] USB: cdc-acm: fix break reporting Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 04/25] ovl: fix missing negative dentry check in ovl_rename() Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 05/25] nfsd4: Handle the NFSv4 READDIR dircount hint being zero Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 06/25] ARM: dts: omap3430-sdp: Fix NAND device node Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 07/25] xtensa: call irqchip_init only when CONFIG_USE_OF is selected Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 08/25] bpf: Fix integer overflow in prealloc_elems_and_freelist() Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 09/25] phy: mdio: fix memory leak Greg Kroah-Hartman
2021-10-14 14:53 ` Greg Kroah-Hartman [this message]
2021-10-14 14:53 ` [PATCH 4.9 11/25] powerpc/fsl/dts: Fix phy-connection-type for fm1mac3 Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 12/25] ptp_pch: Load module automatically if ID matches Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 13/25] ARM: imx6: disable the GIC CPU interface before calling stby-poweroff sequence Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 14/25] net: bridge: use nla_total_size_64bit() in br_get_linkxstats_size() Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 15/25] netlink: annotate data races around nlk->bound Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 16/25] drm/nouveau/debugfs: fix file release memory leak Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 17/25] rtnetlink: fix if_nlmsg_stats_size() under estimation Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 18/25] i40e: fix endless loop under rtnl Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 19/25] gup: document and work around "COW can break either way" issue Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 20/25] HID: apple: Fix logical maximum and usage maximum of Magic Keyboard JIS Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 21/25] netfilter: ip6_tables: zero-initialize fragment offset Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 22/25] mac80211: Drop frames from invalid MAC address in ad-hoc mode Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 23/25] scsi: ses: Fix unsigned comparison with less than zero Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 24/25] scsi: virtio_scsi: Fix spelling mistake "Unsupport" -> "Unsupported" Greg Kroah-Hartman
2021-10-14 14:53 ` [PATCH 4.9 25/25] perf/x86: Reset destroy callback on event init failure Greg Kroah-Hartman
2021-10-14 19:12 ` [PATCH 4.9 00/25] 4.9.287-rc1 review Florian Fainelli
2021-10-14 22:40 ` Shuah Khan
2021-10-15 17:56 ` Daniel Díaz
2021-10-15 22:05 ` Guenter Roeck

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20211014145207.901653380@linuxfoundation.org \
    --to=gregkh@linuxfoundation.org \
    --cc=edumazet@google.com \
    --cc=kuba@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=sashal@kernel.org \
    --cc=stable@vger.kernel.org \
    --cc=syzkaller@googlegroups.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).