general protection fault in tcp_sendpage

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 8fe42840 Merge 4.9.141 into android-4.9
git tree: android-4.9
console output: https://syzkaller.appspot.com/x/log.txt?x=153c315d400000
kernel config: https://syzkaller.appspot.com/x/.config?x=22a5ba9f73b6da1d
dashboard link: https://syzkaller.appspot.com/bug?extid=c35482cf275a990d604b
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1038895d400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17d7b067400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c35482...@syzkaller.appspotmail.com

random: crng init done
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:
CPU: 0 PID: 2044 Comm: syz-executor533 Not tainted 4.9.141+ #1
task: ffff8801d00cc740 task.stack: ffff8801cea68000
RIP: 0010:[<ffffffff824e0ebd>] [<ffffffff824e0ebd>] do_tcp_sendpages
net/ipv4/tcp.c:924 [inline]
RIP: 0010:[<ffffffff824e0ebd>] [<ffffffff824e0ebd>]
tcp_sendpage+0x35d/0x1910 net/ipv4/tcp.c:1033
RSP: 0018:ffff8801cea6f930 EFLAGS: 00010206
RAX: 000000000000000f RBX: 0000000000000000 RCX: 1ffff1003a27c2eb
RDX: 0000000000000000 RSI: ffffffff824e0eab RDI: 0000000000000078
RBP: ffff8801cea6fa98 R08: ffff8801d00ccff0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 000000000000fd58
R13: ffff8801d42ec880 R14: ffff8801d13e1500 R15: dffffc0000000000
FS: 00007f58bb9e7700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020020000 CR3: 00000001d10ba000 CR4: 00000000001606b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
ffff8801cea6f940 ffffffff81243c87 0000000000000246 ffff8801d00cc740
ffffffff830cc2e0 fffffbfff067d37c 0000000000000000 ffff8801d00ccff0
ffffed003a0199fd 0000000000000000 ffff8801d13e18e8 ffff8801cea6f9f0
Call Trace:
[<ffffffff825968b1>] inet_sendpage+0x221/0x510 net/ipv4/af_inet.c:787
[<ffffffff822a0313>] kernel_sendpage+0x93/0xf0 net/socket.c:3334
[<ffffffff822a03fc>] sock_sendpage+0x8c/0xc0 net/socket.c:802
[<ffffffff815a98c6>] pipe_to_sendpage+0x266/0x330 fs/splice.c:470
[<ffffffff815ad926>] splice_from_pipe_feed fs/splice.c:521 [inline]
[<ffffffff815ad926>] __splice_from_pipe+0x316/0x710 fs/splice.c:645
[<ffffffff815af439>] splice_from_pipe+0xf9/0x170 fs/splice.c:680
[<ffffffff815af4ec>] generic_splice_sendpage+0x3c/0x50 fs/splice.c:851
[<ffffffff815b066d>] do_splice_from fs/splice.c:870 [inline]
[<ffffffff815b066d>] do_splice fs/splice.c:1166 [inline]
[<ffffffff815b066d>] SYSC_splice fs/splice.c:1416 [inline]
[<ffffffff815b066d>] SyS_splice+0xe4d/0x14d0 fs/splice.c:1399
[<ffffffff810056ef>] do_syscall_64+0x19f/0x550 arch/x86/entry/common.c:285
[<ffffffff82817893>] entry_SYSCALL_64_after_swapgs+0x5d/0xdb
Code: ff ff 48 0f 44 d8 e8 c3 ab e3 fe 4d 85 e4 0f 84 f0 04 00 00 e8 b5 ab
e3 fe 48 8d 7b 78 44 8b a5 58 ff ff ff 48 89 f8 48 c1 e8 03 <42> 0f b6 04
38 84 c0 74 08 3c 03 0f 8e 06 11 00 00 44 2b 63 78
RIP [<ffffffff824e0ebd>] do_tcp_sendpages net/ipv4/tcp.c:924 [inline]
RIP [<ffffffff824e0ebd>] tcp_sendpage+0x35d/0x1910 net/ipv4/tcp.c:1033
RSP <ffff8801cea6f930>
---[ end trace cbb814e2a57e6682 ]---


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: b95a8c04 ANDROID: uid_sys_stats: Copy task_struct comm fie..
git tree: android-4.4
console output: https://syzkaller.appspot.com/x/log.txt?x=13e85e7d400000
kernel config: https://syzkaller.appspot.com/x/.config?x=5a797996000a8421
dashboard link: https://syzkaller.appspot.com/bug?extid=2943cfccb380a734490e

compiler: gcc (GCC) 8.0.1 20180413 (experimental)

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1648cedb400000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1010000d400000

IMPORTANT: if you fix the bug, please add the following tag to the commit:

Reported-by: syzbot+2943cf...@syzkaller.appspotmail.com

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral
protection fault: 0000 [#1] PREEMPT SMP KASAN
Modules linked in:

CPU: 0 PID: 2091 Comm: syz-executor364 Not tainted 4.4.167+ #4
task: ffff8801d4c84740 task.stack: ffff8801d43d8000
RIP: 0010:[<ffffffff823f592a>] [<ffffffff823f592a>] do_tcp_sendpages
net/ipv4/tcp.c:929 [inline]
RIP: 0010:[<ffffffff823f592a>] [<ffffffff823f592a>]
tcp_sendpage+0x40a/0x17e0 net/ipv4/tcp.c:1033
RSP: 0018:ffff8801d43df988 EFLAGS: 00010206
RAX: 000000000000000f RBX: 000000000000fd58 RCX: 1ffff1001707c193
RDX: 0000000000000000 RSI: ffffffff823f5919 RDI: 0000000000000078
RBP: ffff8801d43dfae8 R08: ffff8801d4c85050 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff823f5520
R13: ffff8800b83e0a40 R14: 0000000000000000 R15: dffffc0000000000
FS: 00007fe017f06700(0000) GS:ffff8801db600000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007fe017ec3e78 CR3: 00000001d4c7f000 CR4: 00000000001606b0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:

9c09e6e5edbfecb0 0000000000000000 ffff8801d4c85008 ffffed003a990a00
fffffbfff0634d24 dffffc0000000000 ffff8801d43dfa08 0000000000000000
ffff8800b83e0e28 ffff8801d43dfa40 0000000600000007 ffff8801d4c84740
Call Trace:
[<ffffffff824a6361>] inet_sendpage+0x221/0x510 net/ipv4/af_inet.c:772
[<ffffffff821d1db3>] kernel_sendpage+0x93/0xf0 net/socket.c:3320
[<ffffffff821d1e9c>] sock_sendpage+0x8c/0xc0 net/socket.c:793
[<ffffffff8152b1c6>] pipe_to_sendpage+0x266/0x330 fs/splice.c:724
[<ffffffff8152dfc4>] splice_from_pipe_feed fs/splice.c:776 [inline]
[<ffffffff8152dfc4>] __splice_from_pipe+0x364/0x790 fs/splice.c:901
[<ffffffff81531089>] splice_from_pipe+0xf9/0x170 fs/splice.c:936
[<ffffffff8153113c>] generic_splice_sendpage+0x3c/0x50 fs/splice.c:1109
[<ffffffff81532251>] do_splice_from fs/splice.c:1128 [inline]
[<ffffffff81532251>] do_splice fs/splice.c:1404 [inline]
[<ffffffff81532251>] SYSC_splice fs/splice.c:1707 [inline]
[<ffffffff81532251>] SyS_splice+0xde1/0x1430 fs/splice.c:1690
[<ffffffff82715ee1>] entry_SYSCALL_64_fastpath+0x1e/0x9a
Code: ff ff ff 4c 0f 44 f0 e8 35 19 f1 fe 48 85 db 0f 84 d4 02 00 00 e8 27
19 f1 fe 49 8d 7e 78 8b 9d 58 ff ff ff 48 89 f8 48 c1 e8 03 <42> 0f b6 04
38 84 c0 74 08 3c 03 0f 8e be 0f 00 00 41 2b 5e 78
RIP [<ffffffff823f592a>] do_tcp_sendpages net/ipv4/tcp.c:929 [inline]
RIP [<ffffffff823f592a>] tcp_sendpage+0x40a/0x17e0 net/ipv4/tcp.c:1033
RSP <ffff8801d43df988>
---[ end trace 01f82cc6c3cd8859 ]---