Hello, syzbot found the following issue on: HEAD commit: 16a8829130ca nfs: fix another case of NULL/IS_ERR confusio.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=162c0566280000 kernel config: https://syzkaller.appspot.com/x/.config?x=8bc832f563d8bf38 dashboard link: https://syzkaller.appspot.com/bug?extid=79f283f1f4ccc6e8b624 compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f8c18a31ba47/disk-16a88291.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/03a18f29b7e7/vmlinux-16a88291.xz kernel image: https://storage.googleapis.com/syzbot-assets/1db2407ade1e/bzImage-16a88291.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+79f283f1f4ccc6e8b624@xxxxxxxxxxxxxxxxxxxxxxxxx xfrm0 speed is unknown, defaulting to 1000 ================================================================== BUG: KASAN: slab-use-after-free in siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177 Read of size 4 at addr ffff888034efa0e8 by task kworker/1:4/24211 CPU: 1 PID: 24211 Comm: kworker/1:4 Not tainted 6.4.0-rc1-syzkaller-00012-g16a8829130ca #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 Workqueue: infiniband ib_cache_event_task Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 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 siw_query_port+0x37b/0x3e0 drivers/infiniband/sw/siw/siw_verbs.c:177 iw_query_port drivers/infiniband/core/device.c:2049 [inline] ib_query_port drivers/infiniband/core/device.c:2090 [inline] ib_query_port+0x3c4/0x8f0 drivers/infiniband/core/device.c:2082 ib_cache_update.part.0+0xcf/0x920 drivers/infiniband/core/cache.c:1487 ib_cache_update drivers/infiniband/core/cache.c:1561 [inline] ib_cache_event_task+0x1b1/0x270 drivers/infiniband/core/cache.c:1561 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 </TASK> Allocated by task 14304: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] ____kasan_kmalloc mm/kasan/common.c:333 [inline] __kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:196 [inline] __do_kmalloc_node mm/slab_common.c:966 [inline] __kmalloc_node+0x61/0x1a0 mm/slab_common.c:973 kmalloc_node include/linux/slab.h:579 [inline] kvmalloc_node+0xa2/0x1a0 mm/util.c:604 kvmalloc include/linux/slab.h:697 [inline] kvzalloc include/linux/slab.h:705 [inline] alloc_netdev_mqs+0x9c/0x1250 net/core/dev.c:10626 rtnl_create_link+0xbeb/0xee0 net/core/rtnetlink.c:3315 rtnl_newlink_create net/core/rtnetlink.c:3433 [inline] __rtnl_newlink+0xfd4/0x1840 net/core/rtnetlink.c:3660 rtnl_newlink+0x68/0xa0 net/core/rtnetlink.c:3673 rtnetlink_rcv_msg+0x43d/0xd50 net/core/rtnetlink.c:6395 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2546 netlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1365 netlink_sendmsg+0x925/0xe30 net/netlink/af_netlink.c:1913 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0xde/0x190 net/socket.c:747 __sys_sendto+0x23a/0x340 net/socket.c:2144 __do_sys_sendto net/socket.c:2156 [inline] __se_sys_sendto net/socket.c:2152 [inline] __x64_sys_sendto+0xe1/0x1b0 net/socket.c:2152 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 Freed by task 5268: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3786 [inline] __kmem_cache_free+0xaf/0x2d0 mm/slub.c:3799 kvfree+0x46/0x50 mm/util.c:650 device_release+0xa3/0x240 drivers/base/core.c:2484 kobject_cleanup lib/kobject.c:683 [inline] kobject_release lib/kobject.c:714 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1c2/0x4d0 lib/kobject.c:731 netdev_run_todo+0x762/0x1100 net/core/dev.c:10400 xfrmi_exit_batch_net+0x2c7/0x3e0 net/xfrm/xfrm_interface_core.c:984 ops_exit_list+0x125/0x170 net/core/net_namespace.c:175 cleanup_net+0x4ee/0xb10 net/core/net_namespace.c:614 process_one_work+0x99a/0x15e0 kernel/workqueue.c:2405 worker_thread+0x67d/0x10c0 kernel/workqueue.c:2552 kthread+0x344/0x440 kernel/kthread.c:379 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308 The buggy address belongs to the object at ffff888034efa000 which belongs to the cache kmalloc-cg-4k of size 4096 The buggy address is located 232 bytes inside of freed 4096-byte region [ffff888034efa000, ffff888034efb000) The buggy address belongs to the physical page: page:ffffea0000d3be00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x34ef8 head:ffffea0000d3be00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 memcg:ffff88807d3a3741 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 ffff88801244f500 ffffea00005adc00 dead000000000002 raw: 0000000000000000 0000000000040004 00000001ffffffff ffff88807d3a3741 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4668, tgid 4668 (dhcpcd), ts 914718336210, free_ts 914216762552 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 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x25f/0x390 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3192 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3291 __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] __kmem_cache_alloc_node+0x136/0x320 mm/slub.c:3490 __do_kmalloc_node mm/slab_common.c:965 [inline] __kmalloc_node+0x51/0x1a0 mm/slab_common.c:973 kmalloc_node include/linux/slab.h:579 [inline] kvmalloc_node+0xa2/0x1a0 mm/util.c:604 kvmalloc include/linux/slab.h:697 [inline] seq_buf_alloc fs/seq_file.c:38 [inline] seq_read_iter+0x7fb/0x12d0 fs/seq_file.c:210 kernfs_fop_read_iter+0x4ce/0x690 fs/kernfs/file.c:279 call_read_iter include/linux/fs.h:1862 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x4b1/0x8a0 fs/read_write.c:470 ksys_read+0x12b/0x250 fs/read_write.c:613 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] slab_alloc_node mm/slub.c:3451 [inline] slab_alloc mm/slub.c:3459 [inline] __kmem_cache_alloc_lru mm/slub.c:3466 [inline] kmem_cache_alloc+0x17c/0x3b0 mm/slub.c:3475 getname_flags.part.0+0x50/0x4f0 fs/namei.c:140 getname_flags+0x9e/0xe0 include/linux/audit.h:321 vfs_fstatat+0x77/0xb0 fs/stat.c:275 __do_sys_newfstatat+0x8a/0x110 fs/stat.c:446 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 Memory state around the buggy address: ffff888034ef9f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888034efa000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888034efa080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888034efa100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888034efa180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== --- This report is generated by a bot. 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