syzbot


WARNING in mtrr_type_lookup_variable

Status: closed as invalid on 2020/03/02 08:12
Reported-by: syzbot+76cf5788ff1f79d551c0@syzkaller.appspotmail.com
First crash: 1054d, last: 877d

Sample crash report:
audit: type=1400 audit(1565451303.671:36): avc:  denied  { map } for  pid=6865 comm="syz-executor654" path="/root/syz-executor654759355" dev="sda1" ino=16484 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1
------------[ cut here ]------------
audit: type=1400 audit(1565451303.671:37): avc:  denied  { map } for  pid=6865 comm="syz-executor654" path="/root/file0/mem" dev="devtmpfs" ino=13687 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:memory_device_t:s0 tclass=chr_file permissive=1
WARNING: CPU: 1 PID: 6865 at arch/x86/kernel/cpu/mtrr/generic.c:216 mtrr_type_lookup_variable+0x4ca/0x670 arch/x86/kernel/cpu/mtrr/generic.c:216
Kernel panic - not syncing: panic_on_warn set ...

CPU: 1 PID: 6865 Comm: syz-executor654 Not tainted 4.14.138 #34
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x138/0x19c lib/dump_stack.c:53
 panic+0x1f2/0x426 kernel/panic.c:182
 __warn.cold+0x2f/0x36 kernel/panic.c:546
 report_bug+0x216/0x254 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:177 [inline]
 fixup_bug arch/x86/kernel/traps.c:172 [inline]
 do_error_trap+0x1bb/0x310 arch/x86/kernel/traps.c:295
 do_invalid_op+0x1b/0x20 arch/x86/kernel/traps.c:314
 invalid_op+0x1b/0x40 arch/x86/entry/entry_64.S:963
RIP: 0010:mtrr_type_lookup_variable+0x4ca/0x670 arch/x86/kernel/cpu/mtrr/generic.c:216
RSP: 0018:ffff8880a5c177b0 EFLAGS: 00010297
RAX: ffff8880a801e540 RBX: 00000000c0000000 RCX: ffffffff885be4a0
audit: type=1400 audit(1565451303.701:38): avc:  denied  { associate } for  pid=6795 comm="restorecond" name="/" dev="devtmpfs" ino=3 scontext=unconfined_u:object_r:user_home_t:s0 tcontext=system_u:object_r:device_t:s0 tclass=filesystem permissive=1
RDX: 0000000000000000 RSI: 02000000c0001000 RDI: ffffffff885be4ac
RBP: ffff8880a5c17880 R08: ffff8880a5c178f8 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8880a801e540 R12: 00003fffc0000000
R13: 0000000000000000 R14: 0000000040000000 R15: dffffc0000000000
 mtrr_type_lookup+0x10e/0x370 arch/x86/kernel/cpu/mtrr/generic.c:285
 pat_x_mtrr_type arch/x86/mm/pat.c:395 [inline]
 reserve_memtype arch/x86/mm/pat.c:558 [inline]
 reserve_memtype+0x2f4/0x640 arch/x86/mm/pat.c:528
 reserve_pfn_range+0x11c/0x390 arch/x86/mm/pat.c:868
 track_pfn_remap+0x15a/0x240 arch/x86/mm/pat.c:960
 remap_pfn_range+0x1bc/0xaa0 mm/memory.c:2108
 mmap_mem+0x1e1/0x281 drivers/char/mem.c:387
 call_mmap include/linux/fs.h:1782 [inline]
 mmap_region+0x852/0x1030 mm/mmap.c:1723
 do_mmap+0x5b8/0xcd0 mm/mmap.c:1501
 do_mmap_pgoff include/linux/mm.h:2178 [inline]
 vm_mmap_pgoff+0x17a/0x1d0 mm/util.c:333
 SYSC_mmap_pgoff mm/mmap.c:1551 [inline]
 SyS_mmap_pgoff+0x3ca/0x520 mm/mmap.c:1509
 SYSC_mmap arch/x86/kernel/sys_x86_64.c:100 [inline]
 SyS_mmap+0x16/0x20 arch/x86/kernel/sys_x86_64.c:91
 do_syscall_64+0x1e8/0x640 arch/x86/entry/common.c:292
 entry_SYSCALL_64_after_hwframe+0x42/0xb7
RIP: 0033:0x4401f9
RSP: 002b:00007fffa09254a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004401f9
RDX: 0000000000000000 RSI: 0000000000004000 RDI: 0000000020ffc000
RBP: 00000000006ca018 R08: 0000000000000003 R09: 02000000bfffd000
R10: 0000000000000012 R11: 0000000000000246 R12: 0000000000401a80
R13: 0000000000401b10 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..

Fix bisection attempts:
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2020/02/02 23:25 linux-4.14.y 9fa690a2a016 acb51638 .config log report syz C
ci2-linux-4-14 2020/01/03 23:01 linux-4.14.y 4c5bf01e16a7 acb51638 .config log report syz C
ci2-linux-4-14 2019/12/04 22:36 linux-4.14.y fbc5fe7a54d0 acb51638 .config log report syz C
Crashes (4):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-linux-4-14 2019/08/10 15:37 linux-4.14.y 3ffe1e79c174 acb51638 .config log report syz C
ci2-linux-4-14 2019/09/01 07:08 linux-4.14.y 01fd1694b93c bad3cce2 .config log report
ci2-linux-4-14 2019/08/14 04:11 linux-4.14.y 3ffe1e79c174 ef801a3e .config log report
ci2-linux-4-14 2019/08/10 15:16 linux-4.14.y 3ffe1e79c174 acb51638 .config log report