==================================================================
BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff88803d17442a by task syz.8.4033/21822

CPU: 1 UID: 0 PID: 21822 Comm: syz.8.4033 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 rose_timer_expiry+0x471/0x4b0
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:__sanitizer_cov_trace_pc+0x3c/0x70
Code: 8b 15 e8 a4 e0 10 81 e2 00 01 ff 00 74 11 81 fa 00 01 00 00 75 35 83 b9 3c 16 00 00 00 74 2c 8b 91 18 16 00 00 83 fa 02 75 21 <48> 8b 91 20 16 00 00 48 8b 32 48 8d 7e 01 8b 89 1c 16 00 00 48 39
RSP: 0018:ffffc90002f7eef8 EFLAGS: 00000246
RAX: ffffffff8133c57e RBX: 00007f2164f8ebe9 RCX: ffff88803d815640
RDX: 0000000000000002 RSI: ffffffff8be33660 RDI: 00007f2164f8ebe9
RBP: 0000000000000001 R08: 0000000000000022 R09: 0000000000000000
R10: ffffc90002f7efb8 R11: ffffffff81ac3810 R12: ffff88803d815640
R13: ffff88801a441dc0 R14: dffffc0000000000 R15: 1ffff920005efdf6
 in_gate_area_no_mm+0xe/0x60
 kernel_text_address+0x2d/0xe0
 __kernel_text_address+0xd/0x40
 unwind_get_return_address+0x4d/0x90
 arch_stack_walk+0xfc/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_node_track_caller_noprof+0x271/0x4e0
 kmalloc_reserve+0x136/0x290
 __alloc_skb+0x142/0x2d0
 sctp_packet_transmit+0x2cc/0x2bb0
 sctp_packet_singleton+0x233/0x330
 sctp_outq_flush+0x4f0/0x3140
 sctp_do_sm+0x5332/0x5a20
 sctp_primitive_ASSOCIATE+0x95/0xc0
 __sctp_connect+0x947/0xd50
 sctp_getsockopt_connectx3+0x2c4/0x440
 sctp_getsockopt+0x98a/0xb60
 do_sock_getsockopt+0x372/0x450
 __x64_sys_getsockopt+0x1a5/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f2164f8ebe9
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:00007f2165d76038 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007f21651b5fa0 RCX: 00007f2164f8ebe9
RDX: 000000000000006f RSI: 0000000000000084 RDI: 0000000000000004
RBP: 00007f2165011e19 R08: 00002000000007c0 R09: 0000000000000000
R10: 0000200000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f21651b6038 R14: 00007f21651b5fa0 R15: 00007ffd0f195b08
 </TASK>

Allocated by task 21755:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_noprof+0x27a/0x4f0
 copy_splice_read+0x143/0xa50
 splice_direct_to_actor+0x4d0/0xcc0
 do_splice_direct+0x181/0x270
 do_sendfile+0x4da/0x7e0
 __se_sys_sendfile64+0x13e/0x190
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 21755:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 copy_splice_read+0x903/0xa50
 splice_direct_to_actor+0x4d0/0xcc0
 do_splice_direct+0x181/0x270
 do_sendfile+0x4da/0x7e0
 __se_sys_sendfile64+0x13e/0x190
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88803d174400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff88803d174400, ffff88803d174600)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3d174
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801a441c80 dead000000000100 dead000000000122
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801a441c80 dead000000000100 dead000000000122
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000f45d01 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 12799, tgid 12799 (syz.1.1736), ts 144512291620, free_ts 140457416420
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 allocate_slab+0x65/0x370
 ___slab_alloc+0xbeb/0x1410
 __kmalloc_node_noprof+0x2fd/0x4e0
 allocate_slab+0x16a/0x370
 ___slab_alloc+0xbeb/0x1410
 kmem_cache_alloc_noprof+0x283/0x3c0
 __anon_vma_prepare+0xcb/0x4a0
 __handle_mm_fault+0x4b2d/0x5440
 handle_mm_fault+0x40a/0x8e0
 do_user_addr_fault+0xa81/0x1390
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
page last free pid 12544 tgid 12544 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __slab_free+0x303/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 __kmalloc_noprof+0x224/0x4f0
 tomoyo_realpath_from_path+0xe3/0x5d0
 tomoyo_path_perm+0x213/0x4b0
 security_inode_getattr+0x12f/0x330
 vfs_fstatat+0xb1/0x170
 __x64_sys_newfstatat+0x116/0x190
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88803d174300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88803d174380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803d174400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88803d174480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803d174500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
