On Mon, Dec 2, 2019 at 10:28 PM Oliver Hartkopp <socketcan@xxxxxxxxxxxx> wrote: > > This issue has already been addressed by Jouni Hogander here: > > https://marc.info/?l=linux-can&m=157483684128186 > > The patch is waiting for upstream via linux-can tree. #syz fix: slcan: Fix use-after-free Read in slcan_open > Regards, > Oliver > > On 02/12/2019 18.05, syzbot wrote: > > Hello, > > > > syzbot found the following crash on: > > > > HEAD commit: 32ef9553 Merge tag 'fsnotify_for_v5.5-rc1' of > > git://git.ke.. > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=12a48e9ce00000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=ff560c3de405258c > > dashboard link: > > https://syzkaller.appspot.com/bug?extid=b5ec6fd05ab552a78532 > > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12943882e00000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10562f86e00000 > > > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > > Reported-by: syzbot+b5ec6fd05ab552a78532@xxxxxxxxxxxxxxxxxxxxxxxxx > > > > ================================================================== > > BUG: KASAN: use-after-free in slc_sync drivers/net/can/slcan.c:504 [inline] > > BUG: KASAN: use-after-free in slcan_open+0x8a1/0x9e0 > > drivers/net/can/slcan.c:579 > > Read of size 8 at addr ffff88809a6e0b88 by task syz-executor961/9030 > > > > CPU: 1 PID: 9030 Comm: syz-executor961 Not tainted 5.4.0-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+0x197/0x210 lib/dump_stack.c:118 > > print_address_description.constprop.0.cold+0xd4/0x30b > > mm/kasan/report.c:374 > > __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 > > kasan_report+0x12/0x20 mm/kasan/common.c:634 > > __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:132 > > slc_sync drivers/net/can/slcan.c:504 [inline] > > slcan_open+0x8a1/0x9e0 drivers/net/can/slcan.c:579 > > tty_ldisc_open.isra.0+0xa3/0x110 drivers/tty/tty_ldisc.c:469 > > tty_set_ldisc+0x30e/0x6b0 drivers/tty/tty_ldisc.c:596 > > tiocsetd drivers/tty/tty_io.c:2334 [inline] > > tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2594 > > vfs_ioctl fs/ioctl.c:46 [inline] > > file_ioctl fs/ioctl.c:509 [inline] > > do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 > > ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 > > __do_sys_ioctl fs/ioctl.c:720 [inline] > > __se_sys_ioctl fs/ioctl.c:718 [inline] > > __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 > > do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 > > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > RIP: 0033:0x4429e9 > > Code: e8 dc 02 03 00 48 83 c4 18 c3 0f 1f 80 00 00 00 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 1b 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00 > > RSP: 002b:00007ffc7db87168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 > > RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00000000004429e9 > > RDX: 00000000200000c0 RSI: 0000000000005423 RDI: 0000000000000003 > > RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000003031 > > R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff > > R13: 0000000000000004 R14: 00007ffc7db871dc R15: 0000000000000000 > > > > Allocated by task 9029: > > save_stack+0x23/0x90 mm/kasan/common.c:69 > > set_track mm/kasan/common.c:77 [inline] > > __kasan_kmalloc mm/kasan/common.c:510 [inline] > > __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:483 > > kasan_kmalloc+0x9/0x10 mm/kasan/common.c:524 > > __do_kmalloc_node mm/slab.c:3615 [inline] > > __kmalloc_node+0x4e/0x70 mm/slab.c:3622 > > kmalloc_node include/linux/slab.h:599 [inline] > > kvmalloc_node+0xbd/0x100 mm/util.c:564 > > kvmalloc include/linux/mm.h:670 [inline] > > kvzalloc include/linux/mm.h:678 [inline] > > alloc_netdev_mqs+0x98/0xde0 net/core/dev.c:9730 > > slc_alloc drivers/net/can/slcan.c:533 [inline] > > slcan_open+0x32d/0x9e0 drivers/net/can/slcan.c:590 > > tty_ldisc_open.isra.0+0xa3/0x110 drivers/tty/tty_ldisc.c:469 > > tty_set_ldisc+0x30e/0x6b0 drivers/tty/tty_ldisc.c:596 > > tiocsetd drivers/tty/tty_io.c:2334 [inline] > > tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2594 > > vfs_ioctl fs/ioctl.c:46 [inline] > > file_ioctl fs/ioctl.c:509 [inline] > > do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 > > ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 > > __do_sys_ioctl fs/ioctl.c:720 [inline] > > __se_sys_ioctl fs/ioctl.c:718 [inline] > > __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 > > do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 > > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > > > Freed by task 9029: > > save_stack+0x23/0x90 mm/kasan/common.c:69 > > set_track mm/kasan/common.c:77 [inline] > > kasan_set_free_info mm/kasan/common.c:332 [inline] > > __kasan_slab_free+0x102/0x150 mm/kasan/common.c:471 > > kasan_slab_free+0xe/0x10 mm/kasan/common.c:480 > > __cache_free mm/slab.c:3425 [inline] > > kfree+0x10a/0x2c0 mm/slab.c:3756 > > kvfree+0x61/0x70 mm/util.c:593 > > netdev_freemem net/core/dev.c:9684 [inline] > > free_netdev+0x3c0/0x470 net/core/dev.c:9839 > > slcan_open+0x848/0x9e0 drivers/net/can/slcan.c:620 > > tty_ldisc_open.isra.0+0xa3/0x110 drivers/tty/tty_ldisc.c:469 > > tty_set_ldisc+0x30e/0x6b0 drivers/tty/tty_ldisc.c:596 > > tiocsetd drivers/tty/tty_io.c:2334 [inline] > > tty_ioctl+0xe8d/0x14f0 drivers/tty/tty_io.c:2594 > > vfs_ioctl fs/ioctl.c:46 [inline] > > file_ioctl fs/ioctl.c:509 [inline] > > do_vfs_ioctl+0xdb6/0x13e0 fs/ioctl.c:696 > > ksys_ioctl+0xab/0xd0 fs/ioctl.c:713 > > __do_sys_ioctl fs/ioctl.c:720 [inline] > > __se_sys_ioctl fs/ioctl.c:718 [inline] > > __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:718 > > do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 > > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > > > The buggy address belongs to the object at ffff88809a6e0000 > > which belongs to the cache kmalloc-32k of size 32768 > > The buggy address is located 2952 bytes inside of > > 32768-byte region [ffff88809a6e0000, ffff88809a6e8000) > > The buggy address belongs to the page: > > page:ffffea000269b800 refcount:1 mapcount:0 mapping:ffff8880aa402540 > > index:0x0 compound_mapcount: 0 > > raw: 00fffe0000010200 ffffea000244d008 ffff8880aa401d48 ffff8880aa402540 > > raw: 0000000000000000 ffff88809a6e0000 0000000100000001 0000000000000000 > > page dumped because: kasan: bad access detected > > > > Memory state around the buggy address: > > ffff88809a6e0a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ffff88809a6e0b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > >> ffff88809a6e0b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ^ > > ffff88809a6e0c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ffff88809a6e0c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb > > ================================================================== > > > > > > --- > > 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 > > -- > You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group. > To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@xxxxxxxxxxxxxxxx. > To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/09ad00de-c082-3c69-5b81-ceae5e9cd3c9%40hartkopp.net.
