On Sun, Dec 17, 2017 at 07:20:01AM -0800, syzbot wrote: > Hello, > > syzkaller hit the following crash on > 41d8c16909ebda40f7b4982a7f5e2ad102705ade > git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/master > compiler: gcc (GCC) 7.1.1 20170620 > .config is attached > Raw console output is attached. > C reproducer is attached > syzkaller reproducer is attached. See https://goo.gl/kgGztJ > for information about syzkaller reproducers > > > audit: type=1400 audit(1513163900.780:7): avc: denied { map } for > pid=3115 comm="syzkaller713832" path="/root/syzkaller713832919" dev="sda1" > ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 > tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 > BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 > IP: __read_once_size include/linux/compiler.h:183 [inline] > IP: compound_head include/linux/page-flags.h:147 [inline] > IP: page_mapping+0x13/0x130 mm/util.c:475 > PGD 214186067 P4D 214186067 PUD 213479067 PMD 0 > Oops: 0000 [#1] SMP > Dumping ftrace buffer: > (ftrace buffer empty) > Modules linked in: > CPU: 1 PID: 3115 Comm: syzkaller713832 Not tainted 4.15.0-rc3-next-20171213+ > #66 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:__read_once_size include/linux/compiler.h:183 [inline] > RIP: 0010:compound_head include/linux/page-flags.h:147 [inline] > RIP: 0010:page_mapping+0x13/0x130 mm/util.c:475 > RSP: 0018:ffffc900017abb98 EFLAGS: 00010293 > RAX: ffff880213652240 RBX: 0000000000000000 RCX: ffffffff81377f83 > RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 > RBP: ffffc900017abbb8 R08: 0000000000000000 R09: ffff8802164af250 > R10: 0000000000000000 R11: 0000000000000000 R12: ffff8802164af180 > R13: ffff8802164af000 R14: ffff88020db7b7c0 R15: ffff880213404730 > FS: 00000000021c7880(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000020 CR3: 000000021364f000 CR4: 00000000001406e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > set_page_dirty+0x1b/0x150 mm/page-writeback.c:2544 > rds_atomic_free_op+0x25/0x80 net/rds/rdma.c:481 > rds_message_purge net/rds/message.c:79 [inline] > rds_message_put+0x174/0x1b0 net/rds/message.c:91 > rds_sendmsg+0x7ac/0xcb0 net/rds/send.c:1204 > sock_sendmsg_nosec net/socket.c:636 [inline] > sock_sendmsg+0x51/0x70 net/socket.c:646 > ___sys_sendmsg+0x35e/0x3b0 net/socket.c:2026 > __sys_sendmsg+0x50/0x90 net/socket.c:2060 > SYSC_sendmsg net/socket.c:2071 [inline] > SyS_sendmsg+0x2d/0x50 net/socket.c:2067 > entry_SYSCALL_64_fastpath+0x1f/0x96 > RIP: 0033:0x4400a9 > RSP: 002b:00007fff97b55488 EFLAGS: 00000217 ORIG_RAX: 000000000000002e > RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004400a9 > RDX: 0000000000000040 RSI: 000000002048cfe4 RDI: 0000000000000003 > RBP: 00000000006ca018 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000217 R12: 0000000000401a10 > R13: 0000000000401aa0 R14: 0000000000000000 R15: 0000000000000000 > Code: 14 24 f4 ff 48 c7 c7 c8 57 a4 82 e8 46 01 24 01 0f 1f 84 00 00 00 00 > 00 55 48 89 e5 41 56 41 55 41 54 53 48 89 fb e8 ed 23 f4 ff <4c> 8b 63 20 41 > f6 c4 01 0f 85 c8 00 00 00 e8 da 23 f4 ff 4c 8b > RIP: __read_once_size include/linux/compiler.h:183 [inline] RSP: > ffffc900017abb98 > RIP: compound_head include/linux/page-flags.h:147 [inline] RSP: > ffffc900017abb98 > RIP: page_mapping+0x13/0x130 mm/util.c:475 RSP: ffffc900017abb98 > CR2: 0000000000000020 > ---[ end trace 35e760b7322fed80 ]--- > > > --- > This bug is generated by a dumb bot. It may contain errors. > See https://goo.gl/tpsmEJ for details. > Direct all questions to syzkaller@xxxxxxxxxxxxxxxx. > Please credit me with: Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> > > syzbot will keep track of this bug report. > Once a fix for this bug is merged into any tree, reply to this email with: > #syz fix: exact-commit-title Crash is no longer occurring, was fixed by commit 7d11f77f84b27: #syz fix: RDS: null pointer dereference in rds_atomic_free_op -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
