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Ziyang Xuan ea30388bae ipv6: Fix an uninit variable access bug in __ip6_make_skb()
Syzbot reported a bug as following:

=====================================================
BUG: KMSAN: uninit-value in arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline]
BUG: KMSAN: uninit-value in arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline]
BUG: KMSAN: uninit-value in atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline]
BUG: KMSAN: uninit-value in __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956
 arch_atomic64_inc arch/x86/include/asm/atomic64_64.h:88 [inline]
 arch_atomic_long_inc include/linux/atomic/atomic-long.h:161 [inline]
 atomic_long_inc include/linux/atomic/atomic-instrumented.h:1429 [inline]
 __ip6_make_skb+0x2f37/0x30f0 net/ipv6/ip6_output.c:1956
 ip6_finish_skb include/net/ipv6.h:1122 [inline]
 ip6_push_pending_frames+0x10e/0x550 net/ipv6/ip6_output.c:1987
 rawv6_push_pending_frames+0xb12/0xb90 net/ipv6/raw.c:579
 rawv6_sendmsg+0x297e/0x2e60 net/ipv6/raw.c:922
 inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xa8e/0xe70 net/socket.c:2476
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530
 __sys_sendmsg net/socket.c:2559 [inline]
 __do_sys_sendmsg net/socket.c:2568 [inline]
 __se_sys_sendmsg net/socket.c:2566 [inline]
 __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566
 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

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:766 [inline]
 slab_alloc_node mm/slub.c:3452 [inline]
 __kmem_cache_alloc_node+0x71f/0xce0 mm/slub.c:3491
 __do_kmalloc_node mm/slab_common.c:967 [inline]
 __kmalloc_node_track_caller+0x114/0x3b0 mm/slab_common.c:988
 kmalloc_reserve net/core/skbuff.c:492 [inline]
 __alloc_skb+0x3af/0x8f0 net/core/skbuff.c:565
 alloc_skb include/linux/skbuff.h:1270 [inline]
 __ip6_append_data+0x51c1/0x6bb0 net/ipv6/ip6_output.c:1684
 ip6_append_data+0x411/0x580 net/ipv6/ip6_output.c:1854
 rawv6_sendmsg+0x2882/0x2e60 net/ipv6/raw.c:915
 inet_sendmsg+0x101/0x180 net/ipv4/af_inet.c:827
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xa8e/0xe70 net/socket.c:2476
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2530
 __sys_sendmsg net/socket.c:2559 [inline]
 __do_sys_sendmsg net/socket.c:2568 [inline]
 __se_sys_sendmsg net/socket.c:2566 [inline]
 __x64_sys_sendmsg+0x367/0x540 net/socket.c:2566
 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

It is because icmp6hdr does not in skb linear region under the scenario
of SOCK_RAW socket. Access icmp6_hdr(skb)->icmp6_type directly will
trigger the uninit variable access bug.

Use a local variable icmp6_type to carry the correct value in different
scenarios.

Fixes: 14878f75ab ("[IPV6]: Add ICMPMsgStats MIB (RFC 4293) [rev 2]")
Reported-by: syzbot+8257f4dcef79de670baf@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?id=3d605ec1d0a7f2a269a1a6936ac7f2b85975ee9c
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2023-04-03 10:17:28 +01:00
arch Xtensa fixes for v6.3: 2023-03-29 10:24:07 -07:00
block block: remove obsolete config BLOCK_COMPAT 2023-03-16 09:35:44 -06:00
certs Kbuild updates for v6.3 2023-02-26 11:53:25 -08:00
crypto asymmetric_keys: log on fatal failures in PE/pkcs7 2023-03-21 16:23:56 +00:00
Documentation Raw NAND controller driver fixes: 2023-03-27 09:41:17 -07:00
drivers net: sfp: add quirk enabling 2500Base-x for HG MXPD-483II 2023-04-03 10:01:17 +01:00
fs zonefs: Do not propagate iomap_dio_rw() ENOTBLK error to user space 2023-03-30 20:56:02 +09:00
include net: phylink: add phylink_expects_phy() method 2023-03-31 09:23:41 +01:00
init bootconfig: Change message if no bootconfig with CONFIG_BOOT_CONFIG_FORCE=y 2023-03-22 22:21:43 +09:00
io_uring block-6.3-2023-03-24 2023-03-24 14:10:39 -07:00
ipc Merge branch 'work.namespace' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2023-02-24 19:20:07 -08:00
kernel - Fix a corner case where vruntime of a task is not being sanitized 2023-03-26 09:18:30 -07:00
lib Fixes for 6.3-rc3: 2023-03-25 12:57:34 -07:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm 21 hotfixes, 8 of which are cc:stable. 11 are for MM, the remainder are 2023-03-24 18:06:11 -07:00
net ipv6: Fix an uninit variable access bug in __ip6_make_skb() 2023-04-03 10:17:28 +01:00
rust Rust fixes for 6.3-rc1 2023-03-03 14:51:15 -08:00
samples LoongArch changes for v6.3 2023-03-01 09:27:00 -08:00
scripts checksyscalls: ignore fstat to silence build warning on LoongArch 2023-03-23 17:18:32 -07:00
security keys: Do not cache key in task struct if key is requested from kernel thread 2023-03-21 16:22:40 +00:00
sound ALSA: hda/realtek: Add quirk for Lenovo ZhaoYang CF4620Z 2023-03-29 14:45:07 +02:00
tools Including fixes from CAN and WPAN. 2023-03-30 14:05:21 -07:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM/riscv changes for 6.3 2023-02-15 12:33:28 -05:00
.clang-format cpumask: re-introduce constant-sized cpumask optimizations 2023-03-05 14:30:34 -08:00
.cocciconfig
.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 *.dtso files 2023-02-26 15:28:23 +09:00
.gitignore kbuild: rpm-pkg: move source components to rpmbuild/SOURCES 2023-03-16 22:45:56 +09:00
.mailmap mailmap: add entries for Richard Leitner 2023-03-23 17:18:35 -07:00
.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 There is no particular theme here - mainly quick hits all over the tree. 2023-02-23 17:55:40 -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 Including fixes from CAN and WPAN. 2023-03-30 14:05:21 -07:00
Makefile Linux 6.3-rc4 2023-03-26 14:40:20 -07:00
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.