WSL2-Linux-Kernel/net/llc
Eric Dumazet 2c5d5b13c6 llc: better deal with too small mtu
syzbot loves to set very small mtu on devices, since it brings joy.
We must make llc_ui_sendmsg() fool proof.

usercopy: Kernel memory overwrite attempt detected to wrapped address (offset 0, size 18446612139802320068)!

kernel BUG at mm/usercopy.c:100!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 17464 Comm: syz-executor1 Not tainted 4.17.0-rc3+ #36
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:usercopy_abort+0xbb/0xbd mm/usercopy.c:88
RSP: 0018:ffff8801868bf800 EFLAGS: 00010282
RAX: 000000000000006c RBX: ffffffff87d2fb00 RCX: 0000000000000000
RDX: 000000000000006c RSI: ffffffff81610731 RDI: ffffed0030d17ef6
RBP: ffff8801868bf858 R08: ffff88018daa4200 R09: ffffed003b5c4fb0
R10: ffffed003b5c4fb0 R11: ffff8801dae27d87 R12: ffffffff87d2f8e0
R13: ffffffff87d2f7a0 R14: ffffffff87d2f7a0 R15: ffffffff87d2f7a0
FS:  00007f56a14ac700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2bc21000 CR3: 00000001abeb1000 CR4: 00000000001426f0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000030602
Call Trace:
 check_bogus_address mm/usercopy.c:153 [inline]
 __check_object_size+0x5d9/0x5d9 mm/usercopy.c:256
 check_object_size include/linux/thread_info.h:108 [inline]
 check_copy_size include/linux/thread_info.h:139 [inline]
 copy_from_iter_full include/linux/uio.h:121 [inline]
 memcpy_from_msg include/linux/skbuff.h:3305 [inline]
 llc_ui_sendmsg+0x4b1/0x1530 net/llc/af_llc.c:941
 sock_sendmsg_nosec net/socket.c:629 [inline]
 sock_sendmsg+0xd5/0x120 net/socket.c:639
 __sys_sendto+0x3d7/0x670 net/socket.c:1789
 __do_sys_sendto net/socket.c:1801 [inline]
 __se_sys_sendto net/socket.c:1797 [inline]
 __x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797
 do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455979
RSP: 002b:00007f56a14abc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f56a14ac6d4 RCX: 0000000000455979
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000018
RBP: 000000000072bea0 R08: 00000000200012c0 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000548 R14: 00000000006fbf60 R15: 0000000000000000
Code: 55 c0 e8 c0 55 bb ff ff 75 c8 48 8b 55 c0 4d 89 f9 ff 75 d0 4d 89 e8 48 89 d9 4c 89 e6 41 56 48 c7 c7 80 fa d2 87 e8 a0 0b a3 ff <0f> 0b e8 95 55 bb ff e8 c0 a8 f7 ff 8b 95 14 ff ff ff 4d 89 e8
RIP: usercopy_abort+0xbb/0xbd mm/usercopy.c:88 RSP: ffff8801868bf800

Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-05-08 00:11:40 -04:00
..
Kconfig Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
Makefile [LLC]: Add sysctl support for the LLC timeouts 2005-09-22 04:30:44 -03:00
af_llc.c llc: better deal with too small mtu 2018-05-08 00:11:40 -04:00
llc_c_ac.c llc: delete timers synchronously in llc_sk_free() 2018-04-22 14:55:03 -04:00
llc_c_ev.c net: replace remaining __FUNCTION__ occurrences 2008-03-05 20:47:47 -08:00
llc_c_st.c llc: Make llc_conn_ev_qfyr_t function pointer arrays const 2014-12-10 15:21:24 -05:00
llc_conn.c llc: delete timers synchronously in llc_sk_free() 2018-04-22 14:55:03 -04:00
llc_core.c net, llc: convert llc_sap.refcnt from atomic_t to refcount_t 2017-07-04 22:35:15 +01:00
llc_if.c net: llc: include linux/errno.h instead of asm/errno.h 2014-10-24 15:51:42 -04:00
llc_input.c locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE() 2017-10-25 11:01:08 +02:00
llc_output.c llc: remove noisy WARN from llc_mac_hdr_init 2014-01-28 18:01:32 -08:00
llc_pdu.c [LLC]: skb allocation size for responses 2008-03-31 21:02:47 -07:00
llc_proc.c net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
llc_s_ac.c [LLC]: skb allocation size for responses 2008-03-31 21:02:47 -07:00
llc_s_ev.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
llc_s_st.c llc: Make llc_sap_action_t function pointer arrays const 2014-12-10 15:21:24 -05:00
llc_sap.c net: llc: drop VLA in llc_sap_mcast() 2018-03-12 11:14:06 -04:00
llc_station.c llc2: Collapse remainder of state machine into simple if-else if-statement 2012-09-17 13:04:19 -04:00
sysctl_net_llc.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00