From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Jianlin Shi <jishi@redhat.com>,
Lorenzo Bianconi <lorenzo.bianconi@redhat.com>,
"David S. Miller" <davem@davemloft.net>,
Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 008/101] ipv6: sit: reset ip header pointer in ipip6_rcv
Date: Mon, 15 Apr 2019 20:58:06 +0200 [thread overview]
Message-ID: <20190415183740.808531944@linuxfoundation.org> (raw)
In-Reply-To: <20190415183740.341577907@linuxfoundation.org>
[ Upstream commit bb9bd814ebf04f579be466ba61fc922625508807 ]
ipip6 tunnels run iptunnel_pull_header on received skbs. This can
determine the following use-after-free accessing iph pointer since
the packet will be 'uncloned' running pskb_expand_head if it is a
cloned gso skb (e.g if the packet has been sent though a veth device)
[ 706.369655] BUG: KASAN: use-after-free in ipip6_rcv+0x1678/0x16e0 [sit]
[ 706.449056] Read of size 1 at addr ffffe01b6bd855f5 by task ksoftirqd/1/=
[ 706.669494] Hardware name: HPE ProLiant m400 Server/ProLiant m400 Server, BIOS U02 08/19/2016
[ 706.771839] Call trace:
[ 706.801159] dump_backtrace+0x0/0x2f8
[ 706.845079] show_stack+0x24/0x30
[ 706.884833] dump_stack+0xe0/0x11c
[ 706.925629] print_address_description+0x68/0x260
[ 706.982070] kasan_report+0x178/0x340
[ 707.025995] __asan_report_load1_noabort+0x30/0x40
[ 707.083481] ipip6_rcv+0x1678/0x16e0 [sit]
[ 707.132623] tunnel64_rcv+0xd4/0x200 [tunnel4]
[ 707.185940] ip_local_deliver_finish+0x3b8/0x988
[ 707.241338] ip_local_deliver+0x144/0x470
[ 707.289436] ip_rcv_finish+0x43c/0x14b0
[ 707.335447] ip_rcv+0x628/0x1138
[ 707.374151] __netif_receive_skb_core+0x1670/0x2600
[ 707.432680] __netif_receive_skb+0x28/0x190
[ 707.482859] process_backlog+0x1d0/0x610
[ 707.529913] net_rx_action+0x37c/0xf68
[ 707.574882] __do_softirq+0x288/0x1018
[ 707.619852] run_ksoftirqd+0x70/0xa8
[ 707.662734] smpboot_thread_fn+0x3a4/0x9e8
[ 707.711875] kthread+0x2c8/0x350
[ 707.750583] ret_from_fork+0x10/0x18
[ 707.811302] Allocated by task 16982:
[ 707.854182] kasan_kmalloc.part.1+0x40/0x108
[ 707.905405] kasan_kmalloc+0xb4/0xc8
[ 707.948291] kasan_slab_alloc+0x14/0x20
[ 707.994309] __kmalloc_node_track_caller+0x158/0x5e0
[ 708.053902] __kmalloc_reserve.isra.8+0x54/0xe0
[ 708.108280] __alloc_skb+0xd8/0x400
[ 708.150139] sk_stream_alloc_skb+0xa4/0x638
[ 708.200346] tcp_sendmsg_locked+0x818/0x2b90
[ 708.251581] tcp_sendmsg+0x40/0x60
[ 708.292376] inet_sendmsg+0xf0/0x520
[ 708.335259] sock_sendmsg+0xac/0xf8
[ 708.377096] sock_write_iter+0x1c0/0x2c0
[ 708.424154] new_sync_write+0x358/0x4a8
[ 708.470162] __vfs_write+0xc4/0xf8
[ 708.510950] vfs_write+0x12c/0x3d0
[ 708.551739] ksys_write+0xcc/0x178
[ 708.592533] __arm64_sys_write+0x70/0xa0
[ 708.639593] el0_svc_handler+0x13c/0x298
[ 708.686646] el0_svc+0x8/0xc
[ 708.739019] Freed by task 17:
[ 708.774597] __kasan_slab_free+0x114/0x228
[ 708.823736] kasan_slab_free+0x10/0x18
[ 708.868703] kfree+0x100/0x3d8
[ 708.905320] skb_free_head+0x7c/0x98
[ 708.948204] skb_release_data+0x320/0x490
[ 708.996301] pskb_expand_head+0x60c/0x970
[ 709.044399] __iptunnel_pull_header+0x3b8/0x5d0
[ 709.098770] ipip6_rcv+0x41c/0x16e0 [sit]
[ 709.146873] tunnel64_rcv+0xd4/0x200 [tunnel4]
[ 709.200195] ip_local_deliver_finish+0x3b8/0x988
[ 709.255596] ip_local_deliver+0x144/0x470
[ 709.303692] ip_rcv_finish+0x43c/0x14b0
[ 709.349705] ip_rcv+0x628/0x1138
[ 709.388413] __netif_receive_skb_core+0x1670/0x2600
[ 709.446943] __netif_receive_skb+0x28/0x190
[ 709.497120] process_backlog+0x1d0/0x610
[ 709.544169] net_rx_action+0x37c/0xf68
[ 709.589131] __do_softirq+0x288/0x1018
[ 709.651938] The buggy address belongs to the object at ffffe01b6bd85580
which belongs to the cache kmalloc-1024 of size 1024
[ 709.804356] The buggy address is located 117 bytes inside of
1024-byte region [ffffe01b6bd85580, ffffe01b6bd85980)
[ 709.946340] The buggy address belongs to the page:
[ 710.003824] page:ffff7ff806daf600 count:1 mapcount:0 mapping:ffffe01c4001f600 index:0x0
[ 710.099914] flags: 0xfffff8000000100(slab)
[ 710.149059] raw: 0fffff8000000100 dead000000000100 dead000000000200 ffffe01c4001f600
[ 710.242011] raw: 0000000000000000 0000000000380038 00000001ffffffff 0000000000000000
[ 710.334966] page dumped because: kasan: bad access detected
Fix it resetting iph pointer after iptunnel_pull_header
Fixes: a09a4c8dd1ec ("tunnels: Remove encapsulation offloads on decap")
Tested-by: Jianlin Shi <jishi@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/ipv6/sit.c | 4 ++++
1 file changed, 4 insertions(+)
diff --git a/net/ipv6/sit.c b/net/ipv6/sit.c
index de9aa5cb295c..8f6cf8e6b5c1 100644
--- a/net/ipv6/sit.c
+++ b/net/ipv6/sit.c
@@ -669,6 +669,10 @@ static int ipip6_rcv(struct sk_buff *skb)
!net_eq(tunnel->net, dev_net(tunnel->dev))))
goto out;
+ /* skb can be uncloned in iptunnel_pull_header, so
+ * old iph is no longer valid
+ */
+ iph = (const struct iphdr *)skb_mac_header(skb);
err = IP_ECN_decapsulate(iph, skb);
if (unlikely(err)) {
if (log_ecn_error)
--
2.19.1
next prev parent reply other threads:[~2019-04-15 19:05 UTC|newest]
Thread overview: 111+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-04-15 18:57 [PATCH 4.19 000/101] 4.19.35-stable review Greg Kroah-Hartman
2019-04-15 18:57 ` [PATCH 4.19 001/101] kvm: nVMX: NMI-window and interrupt-window exiting should wake L2 from HLT Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 002/101] drm/i915/gvt: do not let pin count of shadow mm go negative Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 003/101] powerpc/tm: Limit TM code inside PPC_TRANSACTIONAL_MEM Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 004/101] hv_netvsc: Fix unwanted wakeup after tx_disable Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 005/101] ibmvnic: Fix completion structure initialization Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 006/101] ip6_tunnel: Match to ARPHRD_TUNNEL6 for dev type Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 007/101] ipv6: Fix dangling pointer when ipv6 fragment Greg Kroah-Hartman
2019-04-15 18:58 ` Greg Kroah-Hartman [this message]
2019-04-15 18:58 ` [PATCH 4.19 009/101] kcm: switch order of device registration to fix a crash Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 010/101] net: ethtool: not call vzalloc for zero sized memory request Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 011/101] net-gro: Fix GRO flush when receiving a GSO packet Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 012/101] net/mlx5: Decrease default mr cache size Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 013/101] netns: provide pure entropy for net_hash_mix() Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 014/101] net: rds: force to destroy connection if t_sock is NULL in rds_tcp_kill_sock() Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 015/101] net/sched: act_sample: fix divide by zero in the traffic path Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 016/101] net/sched: fix ->get helper of the matchall cls Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 017/101] openvswitch: fix flow actions reallocation Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 018/101] qmi_wwan: add Olicard 600 Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 019/101] r8169: disable ASPM again Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 020/101] sctp: initialize _pad of sockaddr_in before copying to user memory Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 021/101] tcp: Ensure DCTCP reacts to losses Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 022/101] tcp: fix a potential NULL pointer dereference in tcp_sk_exit Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 023/101] vrf: check accept_source_route on the original netdevice Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 024/101] net/mlx5e: Fix error handling when refreshing TIRs Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 025/101] net/mlx5e: Add a lock on tir list Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 026/101] nfp: validate the return code from dev_queue_xmit() Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 027/101] nfp: disable netpoll on representors Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 028/101] bnxt_en: Improve RX consumer index validity check Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 029/101] bnxt_en: Reset device on RX buffer errors Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 030/101] net: ip_gre: fix possible use-after-free in erspan_rcv Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 031/101] net: ip6_gre: fix possible use-after-free in ip6erspan_rcv Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 032/101] net: core: netif_receive_skb_list: unlist skb before passing to pt->func Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 033/101] r8169: disable default rx interrupt coalescing on RTL8168 Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 034/101] net: mlx5: Add a missing check on idr_find, free buf Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 035/101] net/mlx5e: Update xoff formula Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 036/101] net/mlx5e: Update xon formula Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 037/101] kbuild: deb-pkg: fix bindeb-pkg breakage when O= is used Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 038/101] kbuild: clang: choose GCC_TOOLCHAIN_DIR not on LD Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 039/101] x86/vdso: Drop implicit common-page-size linker flag Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 040/101] lib/string.c: implement a basic bcmp Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 041/101] Revert "clk: meson: clean-up clock registration" Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 042/101] netfilter: nfnetlink_cttimeout: pass default timeout policy to obj_to_nlattr Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 043/101] netfilter: nfnetlink_cttimeout: fetch timeouts for udplite and gre, too Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 044/101] arm64: kaslr: Reserve size of ARM64_MEMSTART_ALIGN in linear region Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 045/101] tty: mark Siemens R3964 line discipline as BROKEN Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 046/101] tty: ldisc: add sysctl to prevent autoloading of ldiscs Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 047/101] hwmon: (w83773g) Select REGMAP_I2C to fix build error Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 048/101] ACPICA: Clear status of GPEs before enabling them Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 049/101] ACPICA: Namespace: remove address node from global list after method termination Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 050/101] ALSA: seq: Fix OOB-reads from strlcpy Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 051/101] ALSA: hda/realtek: Enable headset MIC of Acer TravelMate B114-21 with ALC233 Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 052/101] ALSA: hda/realtek - Add quirk for Tuxedo XC 1509 Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 053/101] ALSA: hda - Add two more machines to the power_save_blacklist Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 054/101] mm/huge_memory.c: fix modifying of page protection by insert_pfn_pmd() Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 055/101] arm64: dts: rockchip: fix rk3328 sdmmc0 write errors Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 056/101] parisc: Detect QEMU earlier in boot process Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 057/101] parisc: regs_return_value() should return gpr28 Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 058/101] parisc: also set iaoq_b in instruction_pointer_set() Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 059/101] alarmtimer: Return correct remaining time Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 060/101] drm/i915/gvt: do not deliver a workload if its creation fails Greg Kroah-Hartman
2019-04-15 18:58 ` [PATCH 4.19 061/101] drm/udl: add a release method and delay modeset teardown Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 062/101] kvm: svm: fix potential get_num_contig_pages overflow Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 063/101] include/linux/bitrev.h: fix constant bitrev Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 064/101] mm: writeback: use exact memcg dirty counts Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 065/101] ASoC: intel: Fix crash at suspend/resume after failed codec registration Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 066/101] ASoC: fsl_esai: fix channel swap issue when stream starts Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 067/101] Btrfs: do not allow trimming when a fs is mounted with the nologreplay option Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 068/101] btrfs: prop: fix zstd compression parameter validation Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 069/101] btrfs: prop: fix vanished compression property after failed set Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 070/101] riscv: Fix syscall_get_arguments() and syscall_set_arguments() Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 071/101] block: do not leak memory in bio_copy_user_iov() Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 072/101] block: fix the return errno for direct IO Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 073/101] genirq: Respect IRQCHIP_SKIP_SET_WAKE in irq_chip_set_wake_parent() Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 074/101] genirq: Initialize request_mutex if CONFIG_SPARSE_IRQ=n Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 075/101] virtio: Honour may_reduce_num in vring_create_virtqueue Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 076/101] ARM: dts: rockchip: fix rk3288 cpu opp node reference Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 077/101] ARM: dts: am335x-evmsk: Correct the regulators for the audio codec Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 078/101] ARM: dts: am335x-evm: " Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 079/101] ARM: dts: at91: Fix typo in ISC_D0 on PC9 Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 080/101] arm64: futex: Fix FUTEX_WAKE_OP atomic ops with non-zero result value Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 081/101] arm64: dts: rockchip: fix rk3328 rgmii high tx error rate Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 082/101] arm64: backtrace: Dont bother trying to unwind the userspace stack Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 083/101] xen: Prevent buffer overflow in privcmd ioctl Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 084/101] sched/fair: Do not re-read ->h_load_next during hierarchical load calculation Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 085/101] xtensa: fix return_address Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 086/101] x86/asm: Remove dead __GNUC__ conditionals Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 087/101] x86/asm: Use stricter assembly constraints in bitops Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 088/101] x86/perf/amd: Resolve race condition when disabling PMC Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 089/101] x86/perf/amd: Resolve NMI latency issues for active PMCs Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 090/101] x86/perf/amd: Remove need to check "running" bit in NMI handler Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 091/101] PCI: Add function 1 DMA alias quirk for Marvell 9170 SATA controller Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 092/101] PCI: pciehp: Ignore Link State Changes after powering off a slot Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 093/101] dm integrity: change memcmp to strncmp in dm_integrity_ctr Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 094/101] dm: revert 8f50e358153d ("dm: limit the max bio size as BIO_MAX_PAGES * PAGE_SIZE") Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 095/101] dm table: propagate BDI_CAP_STABLE_WRITES to fix sporadic checksum errors Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 096/101] dm integrity: fix deadlock with overlapping I/O Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 097/101] arm64: dts: rockchip: fix vcc_host1_5v pin assign on rk3328-rock64 Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 098/101] arm64: dts: rockchip: Fix vcc_host1_5v GPIO polarity " Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 099/101] ACPICA: AML interpreter: add region addresses in global list during initialization Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 100/101] KVM: x86: nVMX: close leak of L0s x2APIC MSRs (CVE-2019-3887) Greg Kroah-Hartman
2019-04-15 18:59 ` [PATCH 4.19 101/101] KVM: x86: nVMX: fix x2APIC VTPR read intercept Greg Kroah-Hartman
2019-04-16 0:24 ` [PATCH 4.19 000/101] 4.19.35-stable review kernelci.org bot
2019-04-16 10:34 ` Jon Hunter
2019-04-16 11:21 ` Naresh Kamboju
2019-04-16 16:30 ` Guenter Roeck
2019-04-16 21:39 ` shuah
2019-04-16 22:16 ` Bharath Vedartham
2019-04-17 6:15 ` Greg Kroah-Hartman
2019-04-17 6:16 ` Greg Kroah-Hartman
2019-04-17 16:40 ` Bharath Vedartham
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