================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: slab-use-after-free in membarrier_switch_mm kernel/sched/sched.h:3666 [inline] BUG: KASAN: slab-use-after-free in context_switch kernel/sched/core.c:5230 [inline] BUG: KASAN: slab-use-after-free in __schedule+0xc56/0x5fa0 kernel/sched/core.c:6867 Read of size 4 at addr ffff8880341631c0 by task syz-executor/16978 CPU: 0 UID: 0 PID: 16978 Comm: syz-executor Tainted: G U L syzkaller #0 PREEMPT(full) Tainted: [U]=USER, [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0x156/0x4c9 mm/kasan/report.c:482 kasan_report+0xdf/0x1a0 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:186 [inline] kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] membarrier_switch_mm kernel/sched/sched.h:3666 [inline] context_switch kernel/sched/core.c:5230 [inline] __schedule+0xc56/0x5fa0 kernel/sched/core.c:6867 __schedule_loop kernel/sched/core.c:6949 [inline] schedule+0xdd/0x390 kernel/sched/core.c:6964 do_nanosleep+0x206/0x560 kernel/time/hrtimer.c:2116 hrtimer_nanosleep+0x156/0x360 kernel/time/hrtimer.c:2163 common_nsleep+0xa1/0xd0 kernel/time/posix-timers.c:1352 __do_sys_clock_nanosleep kernel/time/posix-timers.c:1398 [inline] __se_sys_clock_nanosleep kernel/time/posix-timers.c:1375 [inline] __x64_sys_clock_nanosleep+0x336/0x480 kernel/time/posix-timers.c:1375 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f754235b84e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007ffe3d003028 EFLAGS: 00000246 ORIG_RAX: 00000000000000e6 RAX: ffffffffffffffda RBX: 0000555588d38500 RCX: 00007f754235b84e RDX: 00007ffe3d003080 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007ffe3d0030ec R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000001388 R13: 00000000000927c0 R14: 000000000013c464 R15: 00007ffe3d003140 Allocated by task 17219: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 unpoison_slab_object mm/kasan/common.c:340 [inline] __kasan_slab_alloc+0x89/0x90 mm/kasan/common.c:366 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_noprof+0x2ad/0x780 mm/slub.c:5270 dup_mm kernel/fork.c:1519 [inline] copy_mm kernel/fork.c:1581 [inline] copy_process+0x422c/0x7770 kernel/fork.c:2218 kernel_clone+0xfc/0x930 kernel/fork.c:2648 __do_sys_clone+0xd9/0x120 kernel/fork.c:2789 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 24764: kasan_save_stack+0x30/0x50 mm/kasan/common.c:57 kasan_save_track+0x14/0x30 mm/kasan/common.c:78 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6674 [inline] kmem_cache_free+0x143/0x720 mm/slub.c:6789 mmdrop include/linux/sched/mm.h:55 [inline] __mmput+0x379/0x410 kernel/fork.c:1185 mmput+0x67/0x80 kernel/fork.c:1196 exit_mm kernel/exit.c:581 [inline] do_exit+0x78a/0x2a30 kernel/exit.c:959 do_group_exit+0xd5/0x2a0 kernel/exit.c:1112 get_signal+0x1ec7/0x21e0 kernel/signal.c:3034 arch_do_signal_or_restart+0x91/0x770 arch/x86/kernel/signal.c:337 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline] exit_to_user_mode_loop+0x86/0x4b0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x4ea/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888034163100 which belongs to the cache mm_struct of size 2968 The buggy address is located 192 bytes inside of freed 2968-byte region [ffff888034163100, ffff888034163c98) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x34160 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff888031470101 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813fe30b40 ffffea0000d5ac00 dead000000000002 raw: 0000000000000000 00000000800a000a 00000000f5000000 ffff888031470101 head: 00fff00000000040 ffff88813fe30b40 ffffea0000d5ac00 dead000000000002 head: 0000000000000000 00000000800a000a 00000000f5000000 ffff888031470101 head: 00fff00000000003 ffffea0000d05801 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 16663, tgid 16663 (syz-executor), ts 783944297340, free_ts 783892799184 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1e1/0x250 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0xe3d/0x2e10 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x26c/0x2410 mm/page_alloc.c:5240 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab mm/slub.c:3248 [inline] new_slab+0x2c4/0x440 mm/slub.c:3302 ___slab_alloc+0xda3/0x1ca0 mm/slub.c:4656 __slab_alloc.isra.0+0x63/0x110 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] kmem_cache_alloc_noprof+0x4ec/0x780 mm/slub.c:5270 dup_mm kernel/fork.c:1519 [inline] copy_mm kernel/fork.c:1581 [inline] copy_process+0x422c/0x7770 kernel/fork.c:2218 kernel_clone+0xfc/0x930 kernel/fork.c:2648 __do_sys_clone+0xd9/0x120 kernel/fork.c:2789 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 16663 tgid 16663 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0x822/0x1130 mm/page_alloc.c:2973 discard_slab mm/slub.c:3346 [inline] __put_partials+0x127/0x160 mm/slub.c:3886 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x47/0xe0 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] __do_kmalloc_node mm/slub.c:5656 [inline] __kmalloc_noprof+0x300/0x9c0 mm/slub.c:5669 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] lsm_blob_alloc+0x68/0x90 security/security.c:192 lsm_sock_alloc security/security.c:4375 [inline] security_sk_alloc+0x2d/0x290 security/security.c:4391 sk_prot_alloc+0x1d1/0x2a0 net/core/sock.c:2248 sk_alloc+0x36/0xe80 net/core/sock.c:2301 inet_create net/ipv4/af_inet.c:328 [inline] inet_create+0x3a0/0x1060 net/ipv4/af_inet.c:254 __sock_create+0x339/0x860 net/socket.c:1605 sock_create net/socket.c:1663 [inline] __sys_socket_create net/socket.c:1700 [inline] __sys_socket+0x14d/0x260 net/socket.c:1747 __do_sys_socket net/socket.c:1761 [inline] __se_sys_socket net/socket.c:1759 [inline] __x64_sys_socket+0x72/0xb0 net/socket.c:1759 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xc9/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888034163080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888034163100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888034163180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888034163200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888034163280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================