From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org,
syzbot+e223cf47ec8ae183f2a0@syzkaller.appspotmail.com,
Tadeusz Struk <tadeusz.struk@linaro.org>,
Willem de Bruijn <willemb@google.com>,
Jakub Kicinski <kuba@kernel.org>
Subject: [PATCH 4.14 02/17] net: ipv6: fix skb_over_panic in __ip6_append_data
Date: Fri, 25 Mar 2022 16:04:36 +0100 [thread overview]
Message-ID: <20220325150416.831293702@linuxfoundation.org> (raw)
In-Reply-To: <20220325150416.756136126@linuxfoundation.org>
From: Tadeusz Struk <tadeusz.struk@linaro.org>
commit 5e34af4142ffe68f01c8a9acae83300f8911e20c upstream.
Syzbot found a kernel bug in the ipv6 stack:
LINK: https://syzkaller.appspot.com/bug?id=205d6f11d72329ab8d62a610c44c5e7e25415580
The reproducer triggers it by sending a crafted message via sendmmsg()
call, which triggers skb_over_panic, and crashes the kernel:
skbuff: skb_over_panic: text:ffffffff84647fb4 len:65575 put:65575
head:ffff888109ff0000 data:ffff888109ff0088 tail:0x100af end:0xfec0
dev:<NULL>
Update the check that prevents an invalid packet with MTU equal
to the fregment header size to eat up all the space for payload.
The reproducer can be found here:
LINK: https://syzkaller.appspot.com/text?tag=ReproC&x=1648c83fb00000
Reported-by: syzbot+e223cf47ec8ae183f2a0@syzkaller.appspotmail.com
Signed-off-by: Tadeusz Struk <tadeusz.struk@linaro.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20220310232538.1044947-1-tadeusz.struk@linaro.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/ipv6/ip6_output.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1321,8 +1321,8 @@ static int __ip6_append_data(struct sock
sizeof(struct frag_hdr) : 0) +
rt->rt6i_nfheader_len;
- if (mtu < fragheaderlen ||
- ((mtu - fragheaderlen) & ~7) + fragheaderlen < sizeof(struct frag_hdr))
+ if (mtu <= fragheaderlen ||
+ ((mtu - fragheaderlen) & ~7) + fragheaderlen <= sizeof(struct frag_hdr))
goto emsgsize;
maxfraglen = ((mtu - fragheaderlen) & ~7) + fragheaderlen -
next prev parent reply other threads:[~2022-03-25 15:08 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-25 15:04 [PATCH 4.14 00/17] 4.14.274-rc1 review Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 01/17] nfc: st21nfca: Fix potential buffer overflows in EVT_TRANSACTION Greg Kroah-Hartman
2022-03-25 15:04 ` Greg Kroah-Hartman [this message]
2022-03-25 15:04 ` [PATCH 4.14 03/17] esp: Fix possible buffer overflow in ESP transformation Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 04/17] staging: fbtft: fb_st7789v: reset display before initialization Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 05/17] thermal: int340x: fix memory leak in int3400_notify() Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 06/17] llc: fix netdevice reference leaks in llc_ui_bind() Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 07/17] ALSA: pcm: Add stream lock during PCM reset ioctl operations Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 08/17] ALSA: usb-audio: Add mute TLV for playback volumes on RODE NT-USB Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 09/17] ALSA: cmipci: Restore aux vol on suspend/resume Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 10/17] ALSA: pci: fix reading of swapped values from pcmreg in AC97 codec Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 11/17] drivers: net: xgene: Fix regression in CRC stripping Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 12/17] netfilter: nf_tables: initialize registers in nft_do_chain() Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 13/17] ACPI / x86: Work around broken XSDT on Advantech DAC-BJ01 board Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 14/17] ACPI: battery: Add device HID and quirk for Microsoft Surface Go 3 Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 15/17] ACPI: video: Force backlight native for Clevo NL5xRU and NL5xNU Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 16/17] crypto: qat - disable registration of algorithms Greg Kroah-Hartman
2022-03-25 15:04 ` [PATCH 4.14 17/17] mac80211: fix potential double free on mesh join Greg Kroah-Hartman
2022-03-26 14:29 ` [PATCH 4.14 00/17] 4.14.274-rc1 review Naresh Kamboju
2022-03-27 0:50 ` Guenter Roeck
2022-03-28 14:24 ` Jon Hunter
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