================================================================== BUG: KASAN: slab-use-after-free in tcf_action_destroy+0x50/0x1d0 net/sched/act_api.c:1121 Read of size 8 at addr ffff0000cd350600 by task kworker/u4:15/7018 CPU: 0 PID: 7018 Comm: kworker/u4:15 Not tainted 6.3.0-rc1-syzkaller-gfe15c26ee26e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Workqueue: tc_filter_workqueue fl_destroy_filter_work Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:319 [inline] print_report+0x174/0x514 mm/kasan/report.c:430 kasan_report+0xd4/0x130 mm/kasan/report.c:536 __asan_report_load8_noabort+0x2c/0x38 mm/kasan/report_generic.c:381 tcf_action_destroy+0x50/0x1d0 net/sched/act_api.c:1121 tcf_exts_destroy+0xc0/0x130 net/sched/cls_api.c:3248 __fl_destroy_filter+0x24/0x114 net/sched/cls_flower.c:418 fl_destroy_filter_work+0x20/0x30 net/sched/cls_flower.c:428 process_one_work+0x868/0x16f4 kernel/workqueue.c:2390 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2537 kthread+0x24c/0x2d4 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 Allocated by task 15899: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x7c mm/kasan/common.c:52 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:510 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:196 [inline] kmalloc_trace+0x7c/0x94 mm/slab_common.c:1066 kmalloc include/linux/slab.h:580 [inline] kmalloc_array include/linux/slab.h:635 [inline] kcalloc include/linux/slab.h:667 [inline] tcf_exts_init_ex+0xdc/0x574 net/sched/cls_api.c:3218 fl_change+0x4ec/0x17f0 net/sched/cls_flower.c:2234 tc_new_tfilter+0xe38/0x1614 net/sched/cls_api.c:2310 rtnetlink_rcv_msg+0x780/0xdb8 net/core/rtnetlink.c:6165 netlink_rcv_skb+0x214/0x3c4 net/netlink/af_netlink.c:2574 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6192 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x568/0x81c net/socket.c:2504 ___sys_sendmsg net/socket.c:2558 [inline] __sys_sendmmsg+0x318/0x7d8 net/socket.c:2644 __do_sys_sendmmsg net/socket.c:2673 [inline] __se_sys_sendmmsg net/socket.c:2670 [inline] __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2670 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 Freed by task 15899: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x7c mm/kasan/common.c:52 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:521 ____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook mm/slub.c:1807 [inline] slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0x2c0/0x4b4 mm/slub.c:3800 kfree+0x104/0x228 mm/slab_common.c:1019 tcf_exts_destroy net/sched/cls_api.c:3249 [inline] tcf_exts_init_ex+0x3d8/0x574 net/sched/cls_api.c:3237 fl_change+0x4ec/0x17f0 net/sched/cls_flower.c:2234 tc_new_tfilter+0xe38/0x1614 net/sched/cls_api.c:2310 rtnetlink_rcv_msg+0x780/0xdb8 net/core/rtnetlink.c:6165 netlink_rcv_skb+0x214/0x3c4 net/netlink/af_netlink.c:2574 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:6192 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x660/0x8d4 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x834/0xb18 net/netlink/af_netlink.c:1942 sock_sendmsg_nosec net/socket.c:722 [inline] sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x568/0x81c net/socket.c:2504 ___sys_sendmsg net/socket.c:2558 [inline] __sys_sendmmsg+0x318/0x7d8 net/socket.c:2644 __do_sys_sendmmsg net/socket.c:2673 [inline] __se_sys_sendmmsg net/socket.c:2670 [inline] __arm64_sys_sendmmsg+0xa0/0xbc net/socket.c:2670 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2c0 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x64/0x198 arch/arm64/kernel/syscall.c:193 el0_svc+0x58/0x168 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:591 The buggy address belongs to the object at ffff0000cd350600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 0 bytes inside of freed 256-byte region [ffff0000cd350600, ffff0000cd350700) The buggy address belongs to the physical page: page:00000000319ebac4 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10d350 head:00000000319ebac4 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 ffff0000c0002480 dead000000000122 0000000000000000 raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000cd350500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000cd350580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff0000cd350600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000cd350680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000cd350700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 7018 at lib/refcount.c:87 refcount_dec_not_one+0x228/0x250 lib/refcount.c:87 Modules linked in: CPU: 0 PID: 7018 Comm: kworker/u4:15 Tainted: G B 6.3.0-rc1-syzkaller-gfe15c26ee26e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Workqueue: tc_filter_workqueue fl_destroy_filter_work pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : refcount_dec_not_one+0x228/0x250 lib/refcount.c:87 lr : refcount_dec_not_one+0x228/0x250 lib/refcount.c:87 sp : ffff8000248f7960 x29: ffff8000248f79c0 x28: 00000000c0000000 x27: 1ffff0000491ef30 x26: 1ffff0000491ef2c x25: dfff800000000000 x24: dfff800000000000 x23: 00000000ffffffff x22: 0000000000000000 x21: ffff8000164e30e0 x20: ffff8000186ee000 x19: 0000000000000001 x18: 1fffe000368951b6 x17: ffff800015cdd000 x16: ffff800012461004 x15: 0000000000000000 x14: 0000000040000000 x13: 0000000000000002 x12: 0000000000000001 x11: ff80800008052a1c x10: 0000000040000000 x9 : cca9da6a88f17400 x8 : cca9da6a88f17400 x7 : 1fffe000368951b7 x6 : ffff80000828dc14 x5 : 0000000000000000 x4 : 0000000000000001 x3 : 0000000000000000 x2 : ffff8000248f74a0 x1 : 0000000000000000 x0 : ffff80000828dcb4 Call trace: refcount_dec_not_one+0x228/0x250 lib/refcount.c:87 refcount_dec_and_mutex_lock+0x28/0x158 lib/refcount.c:115 __tcf_action_put+0x4c/0x158 net/sched/act_api.c:377 __tcf_idr_release net/sched/act_api.c:413 [inline] tcf_action_destroy+0xe4/0x1d0 net/sched/act_api.c:1125 tcf_exts_destroy+0xc0/0x130 net/sched/cls_api.c:3248 __fl_destroy_filter+0x24/0x114 net/sched/cls_flower.c:418 fl_destroy_filter_work+0x20/0x30 net/sched/cls_flower.c:428 process_one_work+0x868/0x16f4 kernel/workqueue.c:2390 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2537 kthread+0x24c/0x2d4 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 irq event stamp: 4913965 hardirqs last enabled at (4913965): [] raw_spin_rq_unlock_irq kernel/sched/sched.h:1378 [inline] hardirqs last enabled at (4913965): [] finish_lock_switch+0xbc/0x1e4 kernel/sched/core.c:5062 hardirqs last disabled at (4913964): [] __schedule+0x2a8/0x1fd0 kernel/sched/core.c:6521 softirqs last enabled at (4913752): [] spin_unlock_bh include/linux/spinlock.h:395 [inline] softirqs last enabled at (4913752): [] batadv_nc_purge_paths+0x2f4/0x378 net/batman-adv/network-coding.c:471 softirqs last disabled at (4913750): [] spin_lock_bh include/linux/spinlock.h:355 [inline] softirqs last disabled at (4913750): [] batadv_nc_purge_paths+0xd0/0x378 net/batman-adv/network-coding.c:442 ---[ end trace 0000000000000000 ]--- Unable to handle kernel paging request at virtual address e0fd20a5600007c3 KASAN: maybe wild-memory-access in range [0x07ed052b00003e18-0x07ed052b00003e1f] Mem abort info: ESR = 0x0000000096000004 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x04: level 0 translation fault Data abort info: ISV = 0, ISS = 0x00000004 CM = 0, WnR = 0 [e0fd20a5600007c3] address between user and kernel address ranges Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 7018 Comm: kworker/u4:15 Tainted: G B W 6.3.0-rc1-syzkaller-gfe15c26ee26e #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/02/2023 Workqueue: tc_filter_workqueue fl_destroy_filter_work pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : tcf_action_destroy+0x7c/0x1d0 net/sched/act_api.c:1124 lr : tcf_action_destroy+0x74/0x1d0 net/sched/act_api.c:1123 sp : ffff8000248f7a80 x29: ffff8000248f7a80 x28: ffff0000c1888800 x27: ffff0001021ee470 x26: ffff0000d6a68640 x25: 0000000000000001 x24: dfff800000000000 x23: 0000000000000000 x22: 07ed052b00003e1b x21: ffff0000cd350608 x20: ffff0000cd350600 x19: 0000000000000001 x18: 1fffe000368951b6 x17: ffff800015cdd000 x16: ffff8000085110b0 x15: 0000000000000000 x14: 0000000040000000 x13: 0000000000000002 x12: ffff60002505bc04 x11: ff808000108a4028 x10: 0000000000000000 x9 : ffff800019e59650 x8 : 00fda0a5600007c3 x7 : 1fffe000368951b7 x6 : ffff80000828dc14 x5 : 0000000000000000 x4 : 0000000000000001 x3 : ffff8000108a3f38 x2 : 0000000000000001 x1 : 0000000000000008 x0 : 0000000000000000 Call trace: tcf_action_destroy+0x7c/0x1d0 net/sched/act_api.c:1123 tcf_exts_destroy+0xc0/0x130 net/sched/cls_api.c:3248 __fl_destroy_filter+0x24/0x114 net/sched/cls_flower.c:418 fl_destroy_filter_work+0x20/0x30 net/sched/cls_flower.c:428 process_one_work+0x868/0x16f4 kernel/workqueue.c:2390 worker_thread+0x8e0/0xfe8 kernel/workqueue.c:2537 kthread+0x24c/0x2d4 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 Code: aa1503e0 96039bcc d343fec8 f8397a9f (38786908) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: aa1503e0 mov x0, x21 4: 96039bcc bl 0xfffffffff80e6f34 8: d343fec8 lsr x8, x22, #3 c: f8397a9f str xzr, [x20, x25, lsl #3] * 10: 38786908 ldrb w8, [x8, x24] <-- trapping instruction