================================================================== BUG: KASAN: use-after-free in ax25_addr_ax25dev+0x5c/0x19c net/ax25/ax25_dev.c:38 Read of size 8 at addr ffff0000cfa89608 by task syz.6.466/6494 CPU: 1 PID: 6494 Comm: syz.6.466 Not tainted 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description+0x7c/0x3f0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0x174/0x1e4 mm/kasan/report.c:451 __asan_report_load8_noabort+0x44/0x50 mm/kasan/report_generic.c:309 ax25_addr_ax25dev+0x5c/0x19c net/ax25/ax25_dev.c:38 ax25_bind+0x3f0/0x5b4 net/ax25/af_ax25.c:1134 __sys_bind+0x1e8/0x284 net/socket.c:1720 __do_sys_bind net/socket.c:1731 [inline] __se_sys_bind net/socket.c:1729 [inline] __arm64_sys_bind+0x7c/0x94 net/socket.c:1729 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Allocated by task 4728: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc+0xbc/0xfc mm/kasan/common.c:513 __kasan_kmalloc+0x10/0x1c mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] kmem_cache_alloc_trace+0x27c/0x47c mm/slub.c:3247 kmalloc include/linux/slab.h:591 [inline] kzalloc include/linux/slab.h:721 [inline] ax25_dev_device_up+0x5c/0x548 net/ax25/ax25_dev.c:55 ax25_device_event+0x504/0x590 net/ax25/af_ax25.c:139 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xd4/0x164 kernel/notifier.c:391 __dev_notify_flags+0x2b4/0x540 net/core/dev.c:-1 dev_change_flags+0xc8/0x154 net/core/dev.c:8928 dev_ifsioc+0x140/0xfe4 net/core/dev_ioctl.c:324 dev_ioctl+0x4e0/0xd3c net/core/dev_ioctl.c:587 sock_do_ioctl+0x1dc/0x2dc net/socket.c:1154 sock_ioctl+0x4f4/0x8b0 net/socket.c:1257 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __arm64_sys_ioctl+0x14c/0x1c8 fs/ioctl.c:860 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Freed by task 6398: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x84 mm/kasan/common.c:46 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0x128/0x1ec mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0x178/0x410 mm/slub.c:4559 ax25_dev_put include/net/ax25.h:302 [inline] ax25_release+0x57c/0x82c net/ax25/af_ax25.c:1062 __sock_release net/socket.c:649 [inline] sock_close+0xb8/0x1fc net/socket.c:1336 __fput+0x1c4/0x800 fs/file_table.c:311 ____fput+0x20/0x30 fs/file_table.c:339 task_work_run+0x130/0x1e4 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x262c/0x32b8 arch/arm64/kernel/signal.c:946 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xfc/0x1f0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xd4/0x11c mm/kasan/generic.c:348 insert_work+0x64/0x394 kernel/workqueue.c:1366 __queue_work+0xb84/0x114c kernel/workqueue.c:1532 queue_work_on+0xc4/0x17c kernel/workqueue.c:1559 queue_work include/linux/workqueue.h:512 [inline] addr_event+0x300/0x3f8 drivers/infiniband/core/roce_gid_mgmt.c:853 inet6addr_event+0xf8/0x160 drivers/infiniband/core/roce_gid_mgmt.c:883 notifier_call_chain kernel/notifier.c:83 [inline] atomic_notifier_call_chain+0x174/0x2a0 kernel/notifier.c:198 inet6addr_notifier_call_chain+0x30/0x40 net/ipv6/addrconf_core.c:109 ipv6_add_addr+0x8e4/0xb30 net/ipv6/addrconf.c:1182 inet6_addr_add+0x378/0x81c net/ipv6/addrconf.c:2999 inet6_rtm_newaddr+0x6c0/0x1e28 net/ipv6/addrconf.c:4954 rtnetlink_rcv_msg+0xa7c/0xdb4 net/core/rtnetlink.c:5647 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2489 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:5665 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x664/0x938 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x844/0xb38 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x388/0x4d0 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2071 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Second to last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xd4/0x11c mm/kasan/generic.c:348 insert_work+0x64/0x394 kernel/workqueue.c:1366 __queue_work+0xb84/0x114c kernel/workqueue.c:1532 queue_work_on+0xc4/0x17c kernel/workqueue.c:1559 queue_work include/linux/workqueue.h:512 [inline] addr_event+0x300/0x3f8 drivers/infiniband/core/roce_gid_mgmt.c:853 inetaddr_event+0x108/0x1b0 drivers/infiniband/core/roce_gid_mgmt.c:869 notifier_call_chain kernel/notifier.c:83 [inline] blocking_notifier_call_chain+0xf0/0x198 kernel/notifier.c:318 __inet_insert_ifa+0x8d4/0xad8 net/ipv4/devinet.c:568 inet_rtm_newaddr+0xe90/0x173c net/ipv4/devinet.c:967 rtnetlink_rcv_msg+0xa7c/0xdb4 net/core/rtnetlink.c:5647 netlink_rcv_skb+0x20c/0x3b8 net/netlink/af_netlink.c:2489 rtnetlink_rcv+0x28/0x38 net/core/rtnetlink.c:5665 netlink_unicast_kernel net/netlink/af_netlink.c:1311 [inline] netlink_unicast+0x664/0x938 net/netlink/af_netlink.c:1337 netlink_sendmsg+0x844/0xb38 net/netlink/af_netlink.c:1905 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x388/0x4d0 net/socket.c:2063 __do_sys_sendto net/socket.c:2075 [inline] __se_sys_sendto net/socket.c:2071 [inline] __arm64_sys_sendto+0xd8/0xf8 net/socket.c:2071 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 The buggy address belongs to the object at ffff0000cfa89600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 8 bytes inside of 256-byte region [ffff0000cfa89600, ffff0000cfa89700) The buggy address belongs to the page: page:00000000e8034bec refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000cfa88a00 pfn:0x10fa88 head:00000000e8034bec order:1 compound_mapcount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc00030a8408 fffffc00033bfd88 ffff0000c0002480 raw: ffff0000cfa88a00 000000000010000b 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000cfa89500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000cfa89580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff0000cfa89600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000cfa89680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000cfa89700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== Unable to handle kernel paging request at virtual address 005f809720000390 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 [005f809720000390] address between user and kernel address ranges Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 6494 Comm: syz.6.466 Tainted: G B 5.15.179-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : ax25_addr_ax25dev+0x68/0x19c net/ax25/ax25_dev.c:38 lr : ax25_addr_ax25dev+0x5c/0x19c net/ax25/ax25_dev.c:38 sp : ffff80001d5d7ae0 x29: ffff80001d5d7ae0 x28: 0000000000000100 x27: 1ffff00003abaf64 x26: dfff800000000000 x25: 1fffe0001d17d60c x24: ffff0000d086c028 x23: dfff800000000000 x22: cb0004b900001c86 x21: 0000000000000000 x20: ffff0000cfa89600 x19: ffff80001d5d7c02 x18: 0000000000000203 x17: 0000000000000002 x16: ffff80000824f3a0 x15: 00000000ffffffff x14: ffff0000c2378000 x13: 0000000000000001 x12: 0000000000080000 x11: 00000000000324e3 x10: ffff800024d49000 x9 : 0000000000000000 x8 : 1960009720000390 x7 : 0000000000000000 x6 : 0000000000000001 x5 : ffff80001d5d7178 x4 : 0000000000000000 x3 : ffff80000819cb88 x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000001 Call trace: ax25_addr_ax25dev+0x68/0x19c net/ax25/ax25_dev.c:38 ax25_bind+0x3f0/0x5b4 net/ax25/af_ax25.c:1134 __sys_bind+0x1e8/0x284 net/socket.c:1720 __do_sys_bind net/socket.c:1731 [inline] __se_sys_bind net/socket.c:1729 [inline] __arm64_sys_bind+0x7c/0x94 net/socket.c:1729 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Code: 97c5576c f94002c8 910e2116 d343fec8 (38776908) ---[ end trace 16a4b91fff90ff7f ]--- ---------------- Code disassembly (best guess): 0: 97c5576c bl 0xffffffffff155db0 4: f94002c8 ldr x8, [x22] 8: 910e2116 add x22, x8, #0x388 c: d343fec8 lsr x8, x22, #3 * 10: 38776908 ldrb w8, [x8, x23] <-- trapping instruction