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BUG: KASAN: stack-out-of-bounds in ipmr_ioctl+0x8ef/0x9b0 net/ipv4/ipmr.c:1654
Read of size 4 at addr ffffc90004dffafc by task syz-executor.0/5428

CPU: 1 PID: 5428 Comm: syz-executor.0 Not tainted 6.4.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x64/0xb0 lib/dump_stack.c:106
 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:351
 print_report mm/kasan/report.c:462 [inline]
 kasan_report+0x11c/0x130 mm/kasan/report.c:572
 ipmr_ioctl+0x8ef/0x9b0 net/ipv4/ipmr.c:1654
 sock_ioctl_out net/core/sock.c:4186 [inline]
 sk_ioctl+0x10e/0x340 net/core/sock.c:4214
 inet_ioctl+0x171/0x300 net/ipv4/af_inet.c:1001
 sock_do_ioctl+0xc9/0x1c0 net/socket.c:1189
 sock_ioctl+0x1b1/0x550 net/socket.c:1306
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl fs/ioctl.c:856 [inline]
 __x64_sys_ioctl+0x123/0x190 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f8a83e8c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8a84b29168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f8a83fabf80 RCX: 00007f8a83e8c389
RDX: 0000000000000000 RSI: 00000000000089e1 RDI: 0000000000000003
RBP: 00007f8a83ed7493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fff15e5935f R14: 00007f8a84b29300 R15: 0000000000022000
 </TASK>

The buggy address belongs to stack of task syz-executor.0/5428
 and is located at offset 36 in frame:
 sk_ioctl+0x0/0x340 net/core/sock.c:4172

This frame has 2 objects:
 [32, 36) 'karg'
 [48, 88) 'buffer'

The buggy address belongs to the virtual mapping at
 [ffffc90004df8000, ffffc90004e01000) created by:
 kernel_clone+0xbc/0x640 kernel/fork.c:2915

The buggy address belongs to the physical page:
page:ffffea0000808a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2022a
memcg:ffff88801eb62602
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000000000 00000001ffffffff ffff88801eb62602
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 5427, tgid 5427 (syz-executor.0), ts 72682059050, free_ts 72613482273
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1731
 prep_new_page mm/page_alloc.c:1738 [inline]
 get_page_from_freelist+0xf41/0x2c00 mm/page_alloc.c:3502
 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4768
 vm_area_alloc_pages mm/vmalloc.c:3009 [inline]
 __vmalloc_area_node mm/vmalloc.c:3085 [inline]
 __vmalloc_node_range+0x7ff/0x1070 mm/vmalloc.c:3257
 alloc_thread_stack_node kernel/fork.c:313 [inline]
 dup_task_struct kernel/fork.c:1116 [inline]
 copy_process+0x1181/0x6bf0 kernel/fork.c:2333
 kernel_clone+0xbc/0x640 kernel/fork.c:2915
 __do_sys_clone+0xa1/0xe0 kernel/fork.c:3058
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1302 [inline]
 free_unref_page_prepare+0x62e/0xcb0 mm/page_alloc.c:2564
 free_unref_page+0x33/0x370 mm/page_alloc.c:2659
 __unfreeze_partials+0x17c/0x1a0 mm/slub.c:2636
 qlink_free mm/kasan/quarantine.c:166 [inline]
 qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185
 kasan_quarantine_reduce+0x195/0x220 mm/kasan/quarantine.c:292
 __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:186 [inline]
 slab_post_alloc_hook mm/slab.h:711 [inline]
 kmem_cache_alloc_bulk+0x424/0x860 mm/slub.c:4033
 mt_alloc_bulk lib/maple_tree.c:164 [inline]
 mas_alloc_nodes+0x27c/0x700 lib/maple_tree.c:1309
 mas_node_count_gfp lib/maple_tree.c:1367 [inline]
 mas_preallocate+0x236/0x300 lib/maple_tree.c:5775
 vma_iter_prealloc mm/internal.h:1029 [inline]
 __split_vma+0x16e/0x710 mm/mmap.c:2253
 do_vmi_align_munmap+0x364/0x1230 mm/mmap.c:2398
 do_vmi_munmap+0x1ba/0x210 mm/mmap.c:2530
 mmap_region+0x1b5/0x24b0 mm/mmap.c:2578
 do_mmap+0x5a4/0xd60 mm/mmap.c:1394
 vm_mmap_pgoff+0x164/0x350 mm/util.c:543
 ksys_mmap_pgoff+0x2eb/0x4a0 mm/mmap.c:1440

Memory state around the buggy address:
 ffffc90004dff980: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc90004dffa00: 00 00 00 00 00 00 00 00 f1 f1 f1 f1 00 f3 f3 f3
>ffffc90004dffa80: 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1 04
                                                                ^
 ffffc90004dffb00: f2 00 00 00 00 00 f3 f3 f3 f3 f3 00 00 00 00 00
 ffffc90004dffb80: 00 00 00 00 00 f1 f1 f1 f1 f1 f1 00 00 00 00 00
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