On 3/25/20 7:23 PM, syzbot wrote: > Hello, > > syzbot found the following crash on: > > HEAD commit: e2cf67f6 Merge tag 'zonefs-5.6-rc7' of git://git.kernel.or.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=11c4bd39e00000 > kernel config: https://syzkaller.appspot.com/x/.config?x=2b05d5a033f5be50 > dashboard link: https://syzkaller.appspot.com/bug?extid=b055b1a6b2b958707a21 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13252bf9e00000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1632c813e00000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+b055b1a6b2b958707a21@xxxxxxxxxxxxxxxxxxxxxxxxx Hi, Please try the patch at https://lore.kernel.org/lkml/89526377-7eb6-b662-e1d8-4430928abde9@xxxxxxxxxxxxx/T/#u thanks. > ================================================================== > BUG: KASAN: stack-out-of-bounds in set_bit include/asm-generic/bitops/instrumented-atomic.h:28 [inline] > BUG: KASAN: stack-out-of-bounds in __node_set include/linux/nodemask.h:130 [inline] > BUG: KASAN: stack-out-of-bounds in mpol_to_str+0x377/0x3be mm/mempolicy.c:2962 > Write of size 8 at addr ffffc90000c7fb60 by task systemd/1 > > CPU: 0 PID: 1 Comm: systemd Not tainted 5.6.0-rc7-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > Call Trace: > __dump_stack lib/dump_stack.c:77 [inline] > dump_stack+0x188/0x20d lib/dump_stack.c:118 > print_address_description.constprop.0.cold+0x5/0x315 mm/kasan/report.c:374 > __kasan_report.cold+0x1a/0x32 mm/kasan/report.c:506 > kasan_report+0xe/0x20 mm/kasan/common.c:641 > check_memory_region_inline mm/kasan/generic.c:185 [inline] > check_memory_region+0x128/0x190 mm/kasan/generic.c:192 > set_bit include/asm-generic/bitops/instrumented-atomic.h:28 [inline] > __node_set include/linux/nodemask.h:130 [inline] > mpol_to_str+0x377/0x3be mm/mempolicy.c:2962 > shmem_show_mpol mm/shmem.c:1406 [inline] > shmem_show_options+0x418/0x630 mm/shmem.c:3609 > show_mountinfo+0x616/0x900 fs/proc_namespace.c:187 > seq_read+0xad0/0x1160 fs/seq_file.c:268 > __vfs_read+0x76/0x100 fs/read_write.c:425 > vfs_read+0x1ea/0x430 fs/read_write.c:461 > ksys_read+0x127/0x250 fs/read_write.c:587 > do_syscall_64+0xf6/0x7d0 arch/x86/entry/common.c:294 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x7f17892db92d > Code: 2d 2c 00 00 75 10 b8 00 00 00 00 0f 05 48 3d 01 f0 ff ff 73 31 c3 48 83 ec 08 e8 de 9b 01 00 48 89 04 24 b8 00 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 27 9c 01 00 48 89 d0 48 83 c4 08 48 3d 01 > RSP: 002b:00007ffc058b86b0 EFLAGS: 00000293 ORIG_RAX: 0000000000000000 > RAX: ffffffffffffffda RBX: 0000556657fec630 RCX: 00007f17892db92d > RDX: 0000000000000400 RSI: 0000556657fec860 RDI: 000000000000002c > RBP: 0000000000000d68 R08: 00007f178ad11500 R09: 00000000000000e0 > R10: 0000556657fecc47 R11: 0000000000000293 R12: 00007f1789596440 > R13: 00007f1789595900 R14: 0000000000000019 R15: 0000000000000000 > > > addr ffffc90000c7fb60 is located in stack of task systemd/1 at offset 40 in frame: > mpol_to_str+0x0/0x3be mm/mempolicy.c:2924 > > this frame has 1 object: > [32, 40) 'nodes' > > Memory state around the buggy address: > ffffc90000c7fa00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 > ffffc90000c7fa80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >> ffffc90000c7fb00: 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3 00 > ^ > ffffc90000c7fb80: 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 00 > ffffc90000c7fc00: 00 00 00 00 00 00 f3 f3 f3 f3 00 00 00 00 00 00 > ================================================================== > > > --- > 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 syzkaller@xxxxxxxxxxxxxxxx. > > 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 > -- ~Randy Reported-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
