syzbot has found a reproducer for the following issue on: HEAD commit: 555f3d7be91a Merge tag '5.17-rc3-ksmbd-server-fixes' of gi.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=16c4c44fb00000 kernel config: https://syzkaller.appspot.com/x/.config?x=266de9da75c71a45 dashboard link: https://syzkaller.appspot.com/bug?extid=c94a3675a626f6333d74 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=137e0c77b00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=140b1eaa700000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+c94a3675a626f6333d74@xxxxxxxxxxxxxxxxxxxxxxxxx ================================================================== BUG: KASAN: use-after-free in __list_add_valid+0x93/0xa0 lib/list_debug.c:26 Read of size 8 at addr ffff88807d24c1e0 by task syz-executor341/3597 CPU: 1 PID: 3597 Comm: syz-executor341 Not tainted 5.17.0-rc3-syzkaller-00020-g555f3d7be91a #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 __list_add_valid+0x93/0xa0 lib/list_debug.c:26 __list_add include/linux/list.h:69 [inline] list_add_tail include/linux/list.h:102 [inline] cma_listen_on_all drivers/infiniband/core/cma.c:2593 [inline] rdma_listen+0x86e/0xde0 drivers/infiniband/core/cma.c:3862 ucma_listen+0x16a/0x210 drivers/infiniband/core/ucma.c:1105 ucma_write+0x25c/0x350 drivers/infiniband/core/ucma.c:1744 vfs_write+0x28e/0xae0 fs/read_write.c:588 ksys_write+0x1ee/0x250 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f0aca906fb9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fffc9f11448 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0aca906fb9 RDX: 0000000000000010 RSI: 0000000020000040 RDI: 0000000000000003 RBP: 0000000000000000 R08: 00007fffc9f115e8 R09: 00007fffc9f115e8 R10: 00007fffc9f115e8 R11: 0000000000000246 R12: 00007fffc9f1145c R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 </TASK> Allocated by task 3596: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:436 [inline] ____kasan_kmalloc mm/kasan/common.c:515 [inline] ____kasan_kmalloc mm/kasan/common.c:474 [inline] __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524 kmalloc include/linux/slab.h:581 [inline] kzalloc include/linux/slab.h:715 [inline] __rdma_create_id+0x5b/0x5c0 drivers/infiniband/core/cma.c:845 rdma_create_user_id+0x79/0xd0 drivers/infiniband/core/cma.c:900 ucma_create_id+0x162/0x360 drivers/infiniband/core/ucma.c:464 ucma_write+0x25c/0x350 drivers/infiniband/core/ucma.c:1744 vfs_write+0x28e/0xae0 fs/read_write.c:588 ksys_write+0x1ee/0x250 fs/read_write.c:643 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Freed by task 3596: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 kasan_set_track+0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:366 [inline] ____kasan_slab_free+0x130/0x160 mm/kasan/common.c:328 kasan_slab_free include/linux/kasan.h:236 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754 slab_free mm/slub.c:3509 [inline] kfree+0xcb/0x280 mm/slub.c:4562 ucma_close_id drivers/infiniband/core/ucma.c:187 [inline] ucma_destroy_private_ctx+0x9ca/0xd20 drivers/infiniband/core/ucma.c:579 ucma_close+0x10a/0x180 drivers/infiniband/core/ucma.c:1809 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 exit_task_work include/linux/task_work.h:32 [inline] do_exit+0xb29/0x2a30 kernel/exit.c:806 do_group_exit+0xd2/0x2f0 kernel/exit.c:935 __do_sys_exit_group kernel/exit.c:946 [inline] __se_sys_exit_group kernel/exit.c:944 [inline] __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:944 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae Last potentially related work creation: kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3026 [inline] call_rcu+0xb1/0x740 kernel/rcu/tree.c:3106 netlink_release+0xf08/0x1db0 net/netlink/af_netlink.c:813 __sock_release+0xcd/0x280 net/socket.c:650 sock_close+0x18/0x20 net/socket.c:1318 __fput+0x286/0x9f0 fs/file_table.c:311 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_user_mode_loop kernel/entry/common.c:175 [inline] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x44/0xae The buggy address belongs to the object at ffff88807d24c000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 480 bytes inside of 2048-byte region [ffff88807d24c000, ffff88807d24c800) The buggy address belongs to the page: page:ffffea0001f49200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d248 head:ffffea0001f49200 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea00052c7e00 dead000000000002 ffff888010c42000 raw: 0000000000000000 0000000080080008 00000001ffffffff 0000000000000000 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 2947, ts 17013492589, free_ts 15683127625 prep_new_page mm/page_alloc.c:2434 [inline] get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271 alloc_slab_page mm/slub.c:1799 [inline] allocate_slab mm/slub.c:1944 [inline] new_slab+0x28a/0x3b0 mm/slub.c:2004 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105 slab_alloc_node mm/slub.c:3196 [inline] slab_alloc mm/slub.c:3238 [inline] __kmalloc+0x2fb/0x340 mm/slub.c:4420 kmalloc include/linux/slab.h:586 [inline] sk_prot_alloc+0x110/0x290 net/core/sock.c:1923 sk_alloc+0x32/0xa80 net/core/sock.c:1976 __netlink_create+0x63/0x2f0 net/netlink/af_netlink.c:645 netlink_create+0x3ad/0x5e0 net/netlink/af_netlink.c:708 __sock_create+0x353/0x790 net/socket.c:1468 sock_create net/socket.c:1519 [inline] __sys_socket+0xef/0x200 net/socket.c:1561 __do_sys_socket net/socket.c:1570 [inline] __se_sys_socket net/socket.c:1568 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1568 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1352 [inline] free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404 free_unref_page_prepare mm/page_alloc.c:3325 [inline] free_unref_page+0x19/0x690 mm/page_alloc.c:3404 free_contig_range+0xa8/0xf0 mm/page_alloc.c:9335 destroy_args+0xa8/0x646 mm/debug_vm_pgtable.c:1018 debug_vm_pgtable+0x298e/0x2a20 mm/debug_vm_pgtable.c:1332 do_one_initcall+0x103/0x650 init/main.c:1300 do_initcall_level init/main.c:1373 [inline] do_initcalls init/main.c:1389 [inline] do_basic_setup init/main.c:1408 [inline] kernel_init_freeable+0x6b1/0x73a init/main.c:1613 kernel_init+0x1a/0x1d0 init/main.c:1502 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff88807d24c080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807d24c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807d24c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807d24c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807d24c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================