================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: use-after-free in atomic64_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:1515 [inline] BUG: KASAN: use-after-free in atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:443 [inline] BUG: KASAN: use-after-free in __mutex_trylock_fast kernel/locking/mutex.c:173 [inline] BUG: KASAN: use-after-free in mutex_lock+0x7f/0xe0 kernel/locking/mutex.c:298 Write of size 8 at addr ffff88810b028040 by task syz.1.1265/4831 CPU: 0 PID: 4831 Comm: syz.1.1265 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0xe2/0x130 mm/kasan/report.c:452 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x280/0x290 mm/kasan/generic.c:189 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic64_try_cmpxchg_acquire include/asm-generic/atomic-instrumented.h:1515 [inline] atomic_long_try_cmpxchg_acquire include/asm-generic/atomic-long.h:443 [inline] __mutex_trylock_fast kernel/locking/mutex.c:173 [inline] mutex_lock+0x7f/0xe0 kernel/locking/mutex.c:298 steam_input_open+0x91/0x160 drivers/hid/hid-steam.c:297 input_open_device+0x14c/0x2a0 drivers/input/input.c:635 evdev_open_device drivers/input/evdev.c:400 [inline] evdev_open+0x4d2/0x5e0 drivers/input/evdev.c:487 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x793/0x1090 fs/open.c:819 vfs_open+0x73/0x80 fs/open.c:942 do_open fs/namei.c:3391 [inline] path_openat+0x27ad/0x3160 fs/namei.c:3509 do_filp_open+0x1b3/0x3e0 fs/namei.c:3536 do_sys_openat2+0x14c/0x6d0 fs/open.c:1217 do_sys_open fs/open.c:1233 [inline] __do_sys_openat fs/open.c:1249 [inline] __se_sys_openat fs/open.c:1244 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1244 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fc8f202a510 Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44 RSP: 002b:00007fc8f0a72b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000400 RCX: 00007fc8f202a510 RDX: 0000000000000400 RSI: 00007fc8f0a72c10 RDI: 00000000ffffff9c RBP: 00007fc8f0a72c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007fc8f2273128 R14: 00007fc8f2273090 R15: 00007ffc695f2098 Allocated by task 277: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] ____kasan_kmalloc mm/kasan/common.c:509 [inline] __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518 kasan_kmalloc include/linux/kasan.h:254 [inline] __kmalloc+0x1a7/0x330 mm/slub.c:4038 kmalloc include/linux/slab.h:557 [inline] kzalloc include/linux/slab.h:664 [inline] fib6_info_alloc+0x34/0xe0 net/ipv6/ip6_fib.c:154 ip6_route_info_create+0x4d2/0x1490 net/ipv6/route.c:3673 ip6_route_add+0x27/0x130 net/ipv6/route.c:3769 addrconf_prefix_route+0x1fd/0x2b0 net/ipv6/addrconf.c:2463 inet6_addr_add+0x50e/0x950 net/ipv6/addrconf.c:3020 inet6_rtm_newaddr+0x684/0x930 net/ipv6/addrconf.c:4961 rtnetlink_rcv_msg+0x9db/0xb90 net/core/rtnetlink.c:5610 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2503 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5628 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] __sys_sendto+0x41d/0x580 net/socket.c:2006 __do_sys_sendto net/socket.c:2018 [inline] __se_sys_sendto net/socket.c:2014 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2014 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 77: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4a/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1600 [inline] slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1626 slab_free mm/slub.c:3208 [inline] kfree+0xc0/0x270 mm/slub.c:4196 skb_free_head net/core/skbuff.c:606 [inline] skb_release_data+0x532/0x670 net/core/skbuff.c:626 skb_release_all net/core/skbuff.c:680 [inline] __kfree_skb net/core/skbuff.c:694 [inline] consume_skb+0xab/0x1f0 net/core/skbuff.c:851 skb_free_datagram+0x28/0xe0 net/core/datagram.c:325 unix_dgram_recvmsg+0x9c0/0xd40 net/unix/af_unix.c:2233 sock_recvmsg_nosec net/socket.c:905 [inline] sock_recvmsg net/socket.c:923 [inline] sock_read_iter+0x2a2/0x340 net/socket.c:996 call_read_iter include/linux/fs.h:2060 [inline] new_sync_read fs/read_write.c:415 [inline] vfs_read+0x874/0xa10 fs/read_write.c:496 ksys_read+0x140/0x240 fs/read_write.c:634 __do_sys_read fs/read_write.c:644 [inline] __se_sys_read fs/read_write.c:642 [inline] __x64_sys_read+0x7b/0x90 fs/read_write.c:642 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu kernel/rcu/tree.c:2980 [inline] call_rcu+0x10e/0x1050 kernel/rcu/tree.c:3054 fib6_info_release include/net/ip6_fib.h:346 [inline] ip6_route_info_create+0xa78/0x1490 net/ipv6/route.c:3755 ip6_route_add+0x27/0x130 net/ipv6/route.c:3769 addrconf_prefix_route+0x1fd/0x2b0 net/ipv6/addrconf.c:2463 inet6_addr_add+0x50e/0x950 net/ipv6/addrconf.c:3020 inet6_rtm_newaddr+0x684/0x930 net/ipv6/addrconf.c:4961 rtnetlink_rcv_msg+0x9db/0xb90 net/core/rtnetlink.c:5610 netlink_rcv_skb+0x1e0/0x430 net/netlink/af_netlink.c:2503 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5628 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x88d/0xb30 net/netlink/af_netlink.c:1914 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] __sys_sendto+0x41d/0x580 net/socket.c:2006 __do_sys_sendto net/socket.c:2018 [inline] __se_sys_sendto net/socket.c:2014 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2014 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff88810b028000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 64 bytes inside of 512-byte region [ffff88810b028000, ffff88810b028200) The buggy address belongs to the page: page:ffffea00042c0a00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10b028 head:ffffea00042c0a00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043080 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd60c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_RETRY_MAYFAIL|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, ts 2810544113, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x179/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5370 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1813 [inline] new_slab+0x84/0x3f0 mm/slub.c:1874 new_slab_objects mm/slub.c:2632 [inline] ___slab_alloc+0x2a6/0x450 mm/slub.c:2796 __slab_alloc+0x63/0xa0 mm/slub.c:2836 slab_alloc_node mm/slub.c:2918 [inline] slab_alloc mm/slub.c:2960 [inline] __kmalloc+0x201/0x330 mm/slub.c:4034 __kmalloc_node include/linux/slab.h:418 [inline] kmalloc_node include/linux/slab.h:575 [inline] kvmalloc_node+0x88/0x130 mm/util.c:612 kvmalloc include/linux/mm.h:833 [inline] kvzalloc include/linux/mm.h:841 [inline] netif_alloc_netdev_queues net/core/dev.c:9911 [inline] alloc_netdev_mqs+0x61e/0xc80 net/core/dev.c:10577 ifb_init_one+0x34/0xb7 drivers/net/ifb.c:309 ifb_init_module+0x73/0xfa drivers/net/ifb.c:338 do_one_initcall+0x187/0x510 init/main.c:1197 do_initcall_level+0x16f/0x2cf init/main.c:1270 do_initcalls+0x50/0x92 init/main.c:1286 do_basic_setup+0x88/0x8f init/main.c:1306 kernel_init_freeable+0x287/0x3be init/main.c:1510 page_owner free stack trace missing Memory state around the buggy address: ffff88810b027f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88810b027f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88810b028000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88810b028080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88810b028100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== general protection fault, probably for non-canonical address 0xec6ca9cdcdec6e72: 0000 [#1] PREEMPT SMP KASAN KASAN: maybe wild-memory-access in range [0x63656e6e6f637390-0x63656e6e6f637397] CPU: 0 PID: 4831 Comm: syz.1.1265 Tainted: G B syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2025 RIP: 0010:mutex_can_spin_on_owner kernel/locking/mutex.c:620 [inline] RIP: 0010:mutex_optimistic_spin kernel/locking/mutex.c:664 [inline] RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:976 [inline] RIP: 0010:__mutex_lock+0x18e/0xc50 kernel/locking/mutex.c:1117 Code: 42 80 3c 28 00 74 08 48 89 df e8 6d 5c 26 fd 4c 8b 3b 49 83 e7 f8 0f 84 93 00 00 00 4c 89 e9 4d 8d 6f 2c 4c 89 e8 48 c1 e8 03 <0f> b6 04 08 84 c0 0f 85 64 08 00 00 41 83 7d 00 00 0f 84 24 01 00 RSP: 0018:ffffc90000ddf4e0 EFLAGS: 00010207 RAX: 0c6cadcdcdec6e72 RBX: ffff88810b028040 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88810b028040 RBP: ffffc90000ddf600 R08: fffffffffffffffb R09: 0000000000000007 R10: ffffed1021605008 R11: 1ffff11021605008 R12: ffff8881112d4f00 R13: 63656e6e6f637394 R14: 0000000000000001 R15: 63656e6e6f637368 FS: 00007fc8f0a736c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5a3b578710 CR3: 000000012aefb000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 Call Trace: __mutex_lock_slowpath+0xe/0x10 kernel/locking/mutex.c:1379 mutex_lock+0xcf/0xe0 kernel/locking/mutex.c:299 steam_input_open+0x91/0x160 drivers/hid/hid-steam.c:297 input_open_device+0x14c/0x2a0 drivers/input/input.c:635 evdev_open_device drivers/input/evdev.c:400 [inline] evdev_open+0x4d2/0x5e0 drivers/input/evdev.c:487 chrdev_open+0x597/0x670 fs/char_dev.c:414 do_dentry_open+0x793/0x1090 fs/open.c:819 vfs_open+0x73/0x80 fs/open.c:942 do_open fs/namei.c:3391 [inline] path_openat+0x27ad/0x3160 fs/namei.c:3509 do_filp_open+0x1b3/0x3e0 fs/namei.c:3536 do_sys_openat2+0x14c/0x6d0 fs/open.c:1217 do_sys_open fs/open.c:1233 [inline] __do_sys_openat fs/open.c:1249 [inline] __se_sys_openat fs/open.c:1244 [inline] __x64_sys_openat+0x136/0x160 fs/open.c:1244 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7fc8f202a510 Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44 RSP: 002b:00007fc8f0a72b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 0000000000000400 RCX: 00007fc8f202a510 RDX: 0000000000000400 RSI: 00007fc8f0a72c10 RDI: 00000000ffffff9c RBP: 00007fc8f0a72c10 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd R13: 00007fc8f2273128 R14: 00007fc8f2273090 R15: 00007ffc695f2098 Modules linked in: ---[ end trace 5fb2bbad7c434f4c ]--- RIP: 0010:mutex_can_spin_on_owner kernel/locking/mutex.c:620 [inline] RIP: 0010:mutex_optimistic_spin kernel/locking/mutex.c:664 [inline] RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:976 [inline] RIP: 0010:__mutex_lock+0x18e/0xc50 kernel/locking/mutex.c:1117 Code: 42 80 3c 28 00 74 08 48 89 df e8 6d 5c 26 fd 4c 8b 3b 49 83 e7 f8 0f 84 93 00 00 00 4c 89 e9 4d 8d 6f 2c 4c 89 e8 48 c1 e8 03 <0f> b6 04 08 84 c0 0f 85 64 08 00 00 41 83 7d 00 00 0f 84 24 01 00 RSP: 0018:ffffc90000ddf4e0 EFLAGS: 00010207 RAX: 0c6cadcdcdec6e72 RBX: ffff88810b028040 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffff88810b028040 RBP: ffffc90000ddf600 R08: fffffffffffffffb R09: 0000000000000007 R10: ffffed1021605008 R11: 1ffff11021605008 R12: ffff8881112d4f00 R13: 63656e6e6f637394 R14: 0000000000000001 R15: 63656e6e6f637368 FS: 00007fc8f0a736c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5a3b578710 CR3: 000000012aefb000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000600 ---------------- Code disassembly (best guess): 0: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 5: 74 08 je 0xf 7: 48 89 df mov %rbx,%rdi a: e8 6d 5c 26 fd call 0xfd265c7c f: 4c 8b 3b mov (%rbx),%r15 12: 49 83 e7 f8 and $0xfffffffffffffff8,%r15 16: 0f 84 93 00 00 00 je 0xaf 1c: 4c 89 e9 mov %r13,%rcx 1f: 4d 8d 6f 2c lea 0x2c(%r15),%r13 23: 4c 89 e8 mov %r13,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 0f b6 04 08 movzbl (%rax,%rcx,1),%eax <-- trapping instruction 2e: 84 c0 test %al,%al 30: 0f 85 64 08 00 00 jne 0x89a 36: 41 83 7d 00 00 cmpl $0x0,0x0(%r13) 3b: 0f .byte 0xf 3c: 84 24 01 test %ah,(%rcx,%rax,1)