On Mon, Oct 12, 2020 at 8:11 AM syzbot <[email protected]> wrote: > > Hello, > > syzbot found the following issue on: > > HEAD commit: 3dd0130f Merge branch 'akpm' (patches from Andrew) > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=1219a8e8500000 > kernel config: https://syzkaller.appspot.com/x/.config?x=c06bcf3cc963d91c > dashboard link: https://syzkaller.appspot.com/bug?extid=f58fe4bb535845237057 > compiler: gcc (GCC) 10.1.0-syz 20200507 > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=113937fb900000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1049031b900000 > > Bisection is inconclusive: the issue happens on the oldest tested release. > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=12d57007900000 > final oops: https://syzkaller.appspot.com/x/report.txt?x=11d57007900000 > console output: https://syzkaller.appspot.com/x/log.txt?x=16d57007900000 > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: [email protected] >
I looked at this for a bit, and I think there is a missing range check for one of the members of 'struct vmci_qp_alloc_info' somewhere in the ioctl path. https://syzkaller.appspot.com/x/repro.c?x=1049031b900000 shows what arguments get passed, and while all the members are small, my guess is that something is wrong with the sizes in qp_host_alloc_queue() allocating an array based on produce_size/consume_size, while qp_host_register_user_memory() bases the size on the larger ppn_va/num_ppns. Adding everyone from the git history that did meaningful changes in the past for this driver, as there is no specific maintainer file entry for them to further investigate. Arnd > general protection fault, probably for non-canonical address > 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN > KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] > CPU: 1 PID: 6894 Comm: syz-executor291 Not tainted 5.9.0-rc8-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:compound_head include/linux/page-flags.h:182 [inline] > RIP: 0010:put_page include/linux/mm.h:1172 [inline] > RIP: 0010:qp_release_pages+0x5a/0x310 > drivers/misc/vmw_vmci/vmci_queue_pair.c:635 > Code: 5c ad d1 fc 4d 85 f6 c7 44 24 04 00 00 00 00 0f 85 0f 01 00 00 e9 27 02 > 00 00 e8 c1 b0 d1 fc 48 8d 7d 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 > 62 02 00 00 48 8b 45 08 31 ff 49 89 c4 48 89 > RSP: 0018:ffffc900014e7948 EFLAGS: 00010202 > RAX: 0000000000000001 RBX: ffff8880a06990d0 RCX: ffffffff84a48f81 > RDX: ffff88808e3ec300 RSI: ffffffff84a48e4f RDI: 0000000000000008 > RBP: 0000000000000000 R08: 0000000000000001 R09: ffff8880960634ff > R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffd > R13: dffffc0000000000 R14: fffffffffffffff2 R15: 0000000000000000 > FS: 0000000001e5e880(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000040 CR3: 00000000a1e74000 CR4: 00000000001506e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > qp_host_get_user_memory+0x249/0x3e0 > drivers/misc/vmw_vmci/vmci_queue_pair.c:660 > qp_host_register_user_memory drivers/misc/vmw_vmci/vmci_queue_pair.c:704 > [inline] > qp_broker_create drivers/misc/vmw_vmci/vmci_queue_pair.c:1383 [inline] > qp_broker_alloc+0x10f9/0x1bf0 drivers/misc/vmw_vmci/vmci_queue_pair.c:1737 > vmci_qp_broker_alloc+0x48/0x60 drivers/misc/vmw_vmci/vmci_queue_pair.c:1930 > vmci_host_do_alloc_queuepair.constprop.0+0x1b4/0x400 > drivers/misc/vmw_vmci/vmci_host.c:488 > vmci_host_unlocked_ioctl+0x13cc/0x1e60 drivers/misc/vmw_vmci/vmci_host.c:927 > vfs_ioctl fs/ioctl.c:48 [inline] > __do_sys_ioctl fs/ioctl.c:753 [inline] > __se_sys_ioctl fs/ioctl.c:739 [inline] > __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739 > do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 > entry_SYSCALL_64_after_hwframe+0x44/0xa9 > RIP: 0033:0x4402f9 > Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 > 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f > 83 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007ffd6af99eb8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004402f9 > RDX: 0000000020000100 RSI: 00000000000007a8 RDI: 0000000000000003 > RBP: 00000000006ca018 R08: 00000000004002c8 R09: 00000000004002c8 > R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000401b00 > R13: 0000000000401b90 R14: 0000000000000000 R15: 0000000000000000 > Modules linked in: > ---[ end trace 5d73c037702bf45c ]--- > RIP: 0010:compound_head include/linux/page-flags.h:182 [inline] > RIP: 0010:put_page include/linux/mm.h:1172 [inline] > RIP: 0010:qp_release_pages+0x5a/0x310 > drivers/misc/vmw_vmci/vmci_queue_pair.c:635 > Code: 5c ad d1 fc 4d 85 f6 c7 44 24 04 00 00 00 00 0f 85 0f 01 00 00 e9 27 02 > 00 00 e8 c1 b0 d1 fc 48 8d 7d 08 48 89 f8 48 c1 e8 03 <42> 80 3c 28 00 0f 85 > 62 02 00 00 48 8b 45 08 31 ff 49 89 c4 48 89 > RSP: 0018:ffffc900014e7948 EFLAGS: 00010202 > RAX: 0000000000000001 RBX: ffff8880a06990d0 RCX: ffffffff84a48f81 > RDX: ffff88808e3ec300 RSI: ffffffff84a48e4f RDI: 0000000000000008 > RBP: 0000000000000000 R08: 0000000000000001 R09: ffff8880960634ff > R10: 0000000000000000 R11: 0000000000000000 R12: 00000000fffffffd > R13: dffffc0000000000 R14: fffffffffffffff2 R15: 0000000000000000 > FS: 0000000001e5e880(0000) GS:ffff8880ae500000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000040 CR3: 00000000a1e74000 CR4: 00000000001506e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > --- > This report 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 [email protected]. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot. > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > syzbot can test patches for this issue, for details see: > https://goo.gl/tpsmEJ#testing-patches
