KASAN: use-after-free Read in j1939_session

Title	Replies (including bot)	Last reply
[PATCH v1 0/9] can: j1939: fix multiple issues found by syzbot	16 (16)	2019/11/13 10:04
[PATCH 8/9] can: j1939: j1939_can_recv(): add priv refcounting	1 (1)	2019/11/13 09:55
KASAN: use-after-free Read in j1939_session_deactivate	0 (2)	2019/11/08 23:22

vcan0: j1939_xtp_rx_abort_one: 0x0000000017fc679a: 0x00000: (2) System resources were needed for another task so this connection managed session was terminated. vcan0: j1939_tp_rxtimer: 0x000000000eaf12e4: abort rx timeout. Force session deactivation ================================================================== BUG: KASAN: use-after-free in j1939_session_deactivate+0x80/0x90 net/can/j1939/transport.c:1033 Read of size 8 at addr ffff88809958dc00 by task ksoftirqd/0/9 CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.4.0-rc6+ #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 j1939_session_deactivate+0x80/0x90 net/can/j1939/transport.c:1033 j1939_session_deactivate_activate_next+0x17/0x50 net/can/j1939/transport.c:1041 j1939_tp_rxtimer+0xc8/0x27b net/can/j1939/transport.c:1150 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576 hrtimer_run_softirq+0x17e/0x270 kernel/time/hrtimer.c:1593 __do_softirq+0x262/0x98c kernel/softirq.c:292 run_ksoftirqd kernel/softirq.c:603 [inline] run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595 smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 9265: 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 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3550 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:690 [inline] j1939_session_new+0x81/0x3f0 net/can/j1939/transport.c:1384 j1939_tp_send+0x249/0x750 net/can/j1939/transport.c:1846 j1939_sk_send_loop net/can/j1939/socket.c:995 [inline] j1939_sk_sendmsg+0xb76/0x1450 net/can/j1939/socket.c:1100 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:657 ___sys_sendmsg+0x803/0x920 net/socket.c:2311 __sys_sendmsg+0x105/0x1d0 net/socket.c:2356 __compat_sys_sendmsg net/compat.c:642 [inline] __do_compat_sys_sendmsg net/compat.c:649 [inline] __se_compat_sys_sendmsg net/compat.c:646 [inline] __ia32_compat_sys_sendmsg+0x7a/0xb0 net/compat.c:646 do_syscall_32_irqs_on arch/x86/entry/common.c:333 [inline] do_fast_syscall_32+0x27b/0xdb3 arch/x86/entry/common.c:404 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139 Freed by task 9: 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 j1939_session_destroy net/can/j1939/transport.c:272 [inline] __j1939_session_release net/can/j1939/transport.c:280 [inline] kref_put include/linux/kref.h:65 [inline] j1939_session_put+0x134/0x180 net/can/j1939/transport.c:285 j1939_session_deactivate_locked net/can/j1939/transport.c:1021 [inline] j1939_session_deactivate_locked+0x245/0x2f0 net/can/j1939/transport.c:1009 j1939_session_deactivate+0x3d/0x90 net/can/j1939/transport.c:1032 j1939_session_deactivate_activate_next+0x17/0x50 net/can/j1939/transport.c:1041 j1939_tp_rxtimer+0xc8/0x27b net/can/j1939/transport.c:1150 __run_hrtimer kernel/time/hrtimer.c:1514 [inline] __hrtimer_run_queues+0x364/0xe40 kernel/time/hrtimer.c:1576 hrtimer_run_softirq+0x17e/0x270 kernel/time/hrtimer.c:1593 __do_softirq+0x262/0x98c kernel/softirq.c:292 The buggy address belongs to the object at ffff88809958dc00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of 512-byte region [ffff88809958dc00, ffff88809958de00) The buggy address belongs to the page: page:ffffea0002656340 refcount:1 mapcount:0 mapping:ffff8880aa400a80 index:0x0 flags: 0x1fffc0000000200(slab) raw: 01fffc0000000200 ffffea00028faa88 ffffea0002a31c48 ffff8880aa400a80 raw: 0000000000000000 ffff88809958d000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809958db00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88809958db80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88809958dc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88809958dc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88809958dd00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================