================================================================== BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 Read of size 2 at addr ffff88802c7b402a by task syz.0.275/7363 CPU: 1 PID: 7363 Comm: syz.0.275 Not tainted 6.6.100-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x200 mm/kasan/report.c:466 kasan_report+0x117/0x150 mm/kasan/report.c:579 rose_timer_expiry+0x46a/0x4b0 net/rose/rose_timer.c:183 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x52d/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:finish_task_switch+0x26a/0x920 kernel/sched/core.c:5255 Code: 0f 84 37 01 00 00 48 85 db 0f 85 56 01 00 00 e9 f6 04 00 00 4c 8b 75 d0 4c 89 e7 e8 f0 6a 1a 09 e8 fb a3 2f 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc900035b74d8 EFLAGS: 00000286 RAX: aa2bb8628e8f5b00 RBX: 0000000000000000 RCX: aa2bb8628e8f5b00 RDX: dffffc0000000000 RSI: ffffffff8aaaba40 RDI: ffffffff8afc6700 RBP: ffffc900035b7530 R08: ffffffff8e4a7daf R09: 1ffffffff1c94fb5 R10: dffffc0000000000 R11: fffffbfff1c94fb6 R12: ffff88802d038000 R13: dffffc0000000000 R14: ffff888024040000 R15: ffff8880b8f3cf08 context_switch kernel/sched/core.c:5384 [inline] __schedule+0x14da/0x44d0 kernel/sched/core.c:6700 preempt_schedule_irq+0xb5/0x140 kernel/sched/core.c:7010 irqentry_exit+0x67/0x70 kernel/entry/common.c:438 asm_sysvec_reschedule_ipi+0x1a/0x20 arch/x86/include/asm/idtentry.h:692 RIP: 0010:obj_cgroup_charge+0x318/0x620 mm/memcontrol.c:3368 Code: 00 00 00 00 00 00 00 9c 8f 84 24 80 00 00 00 f6 84 24 81 00 00 00 02 0f 85 26 01 00 00 41 f7 c4 00 02 00 00 74 01 fb 45 31 e4 <80> 7c 24 14 00 0f 85 a0 00 00 00 48 8b 44 24 18 49 89 c6 49 c1 ee RSP: 0018:ffffc900035b78a0 EFLAGS: 00000246 RAX: aa2bb8628e8f5b00 RBX: dffffc0000000000 RCX: aa2bb8628e8f5b00 RDX: dffffc0000000000 RSI: ffffffff8aaaba40 RDI: ffffffff8afc6700 RBP: ffffc900035b7988 R08: ffffffff8e4a7daf R09: 1ffffffff1c94fb5 R10: dffffc0000000000 R11: fffffbfff1c94fb6 R12: 0000000000000000 R13: ffff8880b8f37f70 R14: ffff8880b8f37f98 R15: 1ffff920006b6f1c memcg_slab_pre_alloc_hook mm/slab.h:508 [inline] slab_pre_alloc_hook+0x2eb/0x310 mm/slab.h:719 slab_alloc_node mm/slub.c:3467 [inline] slab_alloc mm/slub.c:3493 [inline] __kmem_cache_alloc_lru mm/slub.c:3500 [inline] kmem_cache_alloc+0x5a/0x2e0 mm/slub.c:3509 kmem_cache_zalloc include/linux/slab.h:711 [inline] alloc_empty_file+0x9e/0x1d0 fs/file_table.c:206 alloc_file+0x5c/0x600 fs/file_table.c:293 alloc_file_pseudo+0x17e/0x200 fs/file_table.c:336 dma_buf_getfile drivers/dma-buf/dma-buf.c:547 [inline] dma_buf_export+0x3c5/0x960 drivers/dma-buf/dma-buf.c:632 system_heap_allocate+0x9bb/0xce0 drivers/dma-buf/heaps/system_heap.c:398 dma_heap_buffer_alloc drivers/dma-buf/dma-heap.c:67 [inline] dma_heap_ioctl_allocate drivers/dma-buf/dma-heap.c:111 [inline] dma_heap_ioctl+0x4a8/0x5c0 drivers/dma-buf/dma-heap.c:171 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fc20418e9a9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc204f5d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fc2043b6160 RCX: 00007fc20418e9a9 RDX: 0000200000000040 RSI: 00000000c0184800 RDI: 0000000000000009 RBP: 00007fc204210d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fc2043b6160 R15: 00007ffd974b59e8 Allocated by task 5773: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] kernfs_fop_open+0x3f5/0xcc0 fs/kernfs/file.c:672 do_dentry_open+0x8c6/0x1500 fs/open.c:929 do_open fs/namei.c:3632 [inline] path_openat+0x274b/0x3190 fs/namei.c:3789 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x780 kernel/rcu/tree.c:3452 net_assign_generic net/core/net_namespace.c:118 [inline] ops_init+0x317/0x640 net/core/net_namespace.c:133 __register_pernet_operations net/core/net_namespace.c:1220 [inline] register_pernet_operations+0x2a7/0x5f0 net/core/net_namespace.c:1293 register_pernet_subsys+0x28/0x40 net/core/net_namespace.c:1334 cttimeout_init+0x16/0xb0 net/netfilter/nfnetlink_cttimeout.c:642 do_one_initcall+0x1fd/0x750 init/main.c:1238 do_initcall_level+0x137/0x1f0 init/main.c:1300 do_initcalls+0x69/0xd0 init/main.c:1316 kernel_init_freeable+0x3d2/0x570 init/main.c:1553 kernel_init+0x1d/0x1c0 init/main.c:1443 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88802c7b4000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 42 bytes inside of freed 512-byte region [ffff88802c7b4000, ffff88802c7b4200) The buggy address belongs to the physical page: page:ffffea0000b1ed00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802c7b4000 pfn:0x2c7b4 head:ffffea0000b1ed00 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017841c80 ffffea00009a7510 ffffea000172c510 raw: ffff88802c7b4000 000000000010000f 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 11378783732, free_ts 0 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_page_interleave+0x24/0x1e0 mm/mempolicy.c:2120 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] net_alloc_generic net/core/net_namespace.c:78 [inline] net_assign_generic net/core/net_namespace.c:98 [inline] ops_init+0x207/0x640 net/core/net_namespace.c:133 __register_pernet_operations net/core/net_namespace.c:1220 [inline] register_pernet_operations+0x2a7/0x5f0 net/core/net_namespace.c:1293 register_pernet_subsys+0x28/0x40 net/core/net_namespace.c:1334 nf_conntrack_standalone_init+0x83/0x100 net/netfilter/nf_conntrack_standalone.c:1216 do_one_initcall+0x1fd/0x750 init/main.c:1238 do_initcall_level+0x137/0x1f0 init/main.c:1300 do_initcalls+0x69/0xd0 init/main.c:1316 page_owner free stack trace missing Memory state around the buggy address: ffff88802c7b3f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802c7b3f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88802c7b4000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802c7b4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802c7b4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: 0f 84 37 01 00 00 je 0x13d 6: 48 85 db test %rbx,%rbx 9: 0f 85 56 01 00 00 jne 0x165 f: e9 f6 04 00 00 jmp 0x50a 14: 4c 8b 75 d0 mov -0x30(%rbp),%r14 18: 4c 89 e7 mov %r12,%rdi 1b: e8 f0 6a 1a 09 call 0x91a6b10 20: e8 fb a3 2f 00 call 0x2fa420 25: fb sti 26: 4c 8b 65 c0 mov -0x40(%rbp),%r12 * 2a: 49 8d bc 24 f8 15 00 lea 0x15f8(%r12),%rdi <-- trapping instruction 31: 00 32: 48 89 f8 mov %rdi,%rax 35: 48 c1 e8 03 shr $0x3,%rax 39: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 3e: 84 c0 test %al,%al