netlink: 56 bytes leftover after parsing attributes in process `syz.1.338'. netlink: 56 bytes leftover after parsing attributes in process `syz.1.338'. ================================================================== BUG: KASAN: use-after-free in ax25_addr_ax25dev+0x60/0x19c net/ax25/ax25_dev.c:38 Read of size 8 at addr ffff0000c85e1c08 by task syz.1.338/5423 CPU: 0 PID: 5423 Comm: syz.1.338 Not tainted 5.15.184-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x78/0x30c mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xec/0x15c mm/kasan/report.c:451 __asan_report_load8_noabort+0x44/0x50 mm/kasan/report_generic.c:309 ax25_addr_ax25dev+0x60/0x19c net/ax25/ax25_dev.c:38 ax25_rt_add net/ax25/ax25_route.c:81 [inline] ax25_rt_ioctl+0x698/0x14a4 net/ax25/ax25_route.c:239 ax25_ioctl+0x724/0x1114 net/ax25/af_ax25.c:1819 sock_do_ioctl+0xf8/0x240 net/socket.c:1140 sock_ioctl+0x5c8/0x87c 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+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Allocated by task 4785: 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 mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb0/0xf0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] kmem_cache_alloc_trace+0x274/0x3fc mm/slub.c:3247 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] ax25_dev_device_up+0x5c/0x540 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 call_netdevice_notifiers_info net/core/dev.c:2049 [inline] call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] __dev_notify_flags+0x250/0x46c net/core/dev.c:-1 dev_change_flags+0xc8/0x154 net/core/dev.c:8929 dev_ifsioc+0x504/0xef4 net/core/dev_ioctl.c:324 dev_ioctl+0x4d0/0xc94 net/core/dev_ioctl.c:587 sock_do_ioctl+0x18c/0x240 net/socket.c:1154 sock_ioctl+0x5c8/0x87c 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+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Freed by task 5423: 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+0x128/0x1e8 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0x170/0x40c mm/slub.c:4559 ax25_rt_ioctl+0x97c/0x14a4 net/ax25/ax25_route.c:-1 ax25_ioctl+0x724/0x1114 net/ax25/af_ax25.c:1819 sock_do_ioctl+0xf8/0x240 net/socket.c:1140 sock_ioctl+0x5c8/0x87c 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+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/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+0xcc/0x114 mm/kasan/generic.c:348 insert_work+0x64/0x388 kernel/workqueue.c:1366 __queue_work+0xb30/0x1054 kernel/workqueue.c:1532 queue_work_on+0xc4/0x17c kernel/workqueue.c:1559 queue_work include/linux/workqueue.h:512 [inline] call_usermodehelper_exec+0x22c/0x478 kernel/umh.c:435 kobject_uevent_env+0x670/0x888 lib/kobject_uevent.c:633 kobject_uevent+0x2c/0x3c lib/kobject_uevent.c:657 driver_register+0x29c/0x374 drivers/base/driver.c:248 __platform_driver_register+0x6c/0x80 drivers/base/platform.c:858 zynqmp_pm_platform_driver_init+0x20/0x2c drivers/soc/xilinx/zynqmp_power.c:264 do_one_initcall+0x228/0x8b0 init/main.c:1302 do_initcall_level+0x154/0x214 init/main.c:1375 do_initcalls+0x58/0xac init/main.c:1391 do_basic_setup+0x8c/0xa0 init/main.c:1410 kernel_init_freeable+0x404/0x5fc init/main.c:1615 kernel_init+0x24/0x1d0 init/main.c:1506 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:870 The buggy address belongs to the object at ffff0000c85e1c00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 8 bytes inside of 256-byte region [ffff0000c85e1c00, ffff0000c85e1d00) The buggy address belongs to the page: page:000000009c47d5f1 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1085e0 head:000000009c47d5f1 order:1 compound_mapcount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 fffffc000302cb00 0000000200000002 ffff0000c0002480 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000c85e1b00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000c85e1b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff0000c85e1c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000c85e1c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000c85e1d00: 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 f18b807ee0000316 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 [f18b807ee0000316] address between user and kernel address ranges Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP Modules linked in: CPU: 0 PID: 5423 Comm: syz.1.338 Tainted: G B 5.15.184-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : ax25_addr_ax25dev+0x6c/0x19c net/ax25/ax25_dev.c:38 lr : ax25_addr_ax25dev+0x60/0x19c net/ax25/ax25_dev.c:38 sp : ffff80001fc077c0 x29: ffff80001fc077c0 x28: dfff800000000000 x27: 00000000000089f0 x26: dfff800000000000 x25: ffff80001fc079a0 x24: 000000007ffffffe x23: dfff800000000000 x22: 8c6003f7000018b7 x21: 0000000000000000 x20: ffff0000c85e1c00 x19: ffff80001fc07880 x18: 0000000000000203 x17: 0000000000000002 x16: ffff8000082d4b38 x15: 00000000ffffffff x14: 0000000000ff0100 x13: 0000000000000001 x12: 0000000000080000 x11: 000000000007ffff x10: ffff8000200ca000 x9 : 0000000000000000 x8 : 118c007ee0000316 x7 : 0000000000000000 x6 : 0000000000000001 x5 : ffff80001fc06fd8 x4 : 0000000000000000 x3 : ffff800008184528 x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000001 Call trace: ax25_addr_ax25dev+0x6c/0x19c net/ax25/ax25_dev.c:38 ax25_rt_add net/ax25/ax25_route.c:81 [inline] ax25_rt_ioctl+0x698/0x14a4 net/ax25/ax25_route.c:239 ax25_ioctl+0x724/0x1114 net/ax25/af_ax25.c:1819 sock_do_ioctl+0xf8/0x240 net/socket.c:1140 sock_ioctl+0x5c8/0x87c 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+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Code: 96105147 f94002c8 910e2116 d343fec8 (38776908) ---[ end trace 0ecf3607282ac548 ]--- ---------------- Code disassembly (best guess): 0: 96105147 bl 0xfffffffff841451c 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