================================================================== BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline] BUG: KASAN: use-after-free in check_net include/net/net_namespace.h:254 [inline] BUG: KASAN: use-after-free in rds_destroy_pending net/rds/rds.h:951 [inline] BUG: KASAN: use-after-free in rds_cong_queue_updates+0x209/0x4d0 net/rds/cong.c:229 Read of size 4 at addr ffff88806e040144 by task syz-executor.2/31447 CPU: 1 PID: 31447 Comm: syz-executor.2 Not tainted 5.0.0+ #109 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x172/0x1f0 lib/dump_stack.c:113 print_address_description.cold+0x7c/0x20d mm/kasan/report.c:187 kasan_report.cold+0x1b/0x40 mm/kasan/report.c:317 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x123/0x190 mm/kasan/generic.c:191 kasan_check_read+0x11/0x20 mm/kasan/common.c:102 atomic_read include/asm-generic/atomic-instrumented.h:26 [inline] refcount_read include/linux/refcount.h:43 [inline] check_net include/net/net_namespace.h:254 [inline] rds_destroy_pending net/rds/rds.h:951 [inline] rds_cong_queue_updates+0x209/0x4d0 net/rds/cong.c:229 rds_recv_rcvbuf_delta.part.0+0x34f/0x3f0 net/rds/recv.c:118 rds_recv_rcvbuf_delta net/rds/recv.c:379 [inline] rds_recv_incoming+0x789/0x11f0 net/rds/recv.c:379 rds_loop_xmit+0xf3/0x2a0 net/rds/loop.c:96 rds_send_xmit+0x1113/0x2560 net/rds/send.c:355 rds_sendmsg+0x3017/0x3550 net/rds/send.c:1369 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg+0xdd/0x130 net/socket.c:661 ___sys_sendmsg+0x806/0x930 net/socket.c:2260 __sys_sendmsg+0x105/0x1d0 net/socket.c:2298 __do_sys_sendmsg net/socket.c:2307 [inline] __se_sys_sendmsg net/socket.c:2305 [inline] __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2305 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x458209 Code: ad b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 7b b8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f93889ddc78 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000458209 RDX: 0000000000000000 RSI: 0000000020000200 RDI: 0000000000000003 RBP: 000000000073bf00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f93889de6d4 R13: 00000000004c5899 R14: 00000000004d97f0 R15: 00000000ffffffff Allocated by task 7732: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_kmalloc mm/kasan/common.c:497 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:470 kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:505 slab_post_alloc_hook mm/slab.h:436 [inline] slab_alloc mm/slab.c:3392 [inline] kmem_cache_alloc+0x11a/0x6f0 mm/slab.c:3554 kmem_cache_zalloc include/linux/slab.h:730 [inline] net_alloc net/core/net_namespace.c:384 [inline] copy_net_ns+0xed/0x340 net/core/net_namespace.c:424 create_new_namespaces+0x400/0x7b0 kernel/nsproxy.c:107 unshare_nsproxy_namespaces+0xc2/0x200 kernel/nsproxy.c:206 ksys_unshare+0x440/0x980 kernel/fork.c:2549 __do_sys_unshare kernel/fork.c:2617 [inline] __se_sys_unshare kernel/fork.c:2615 [inline] __x64_sys_unshare+0x31/0x40 kernel/fork.c:2615 do_syscall_64+0x103/0x610 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 18215: save_stack+0x45/0xd0 mm/kasan/common.c:75 set_track mm/kasan/common.c:87 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:459 kasan_slab_free+0xe/0x10 mm/kasan/common.c:467 __cache_free mm/slab.c:3498 [inline] kmem_cache_free+0x86/0x260 mm/slab.c:3764 net_free net/core/net_namespace.c:400 [inline] net_drop_ns.part.0+0x70/0x90 net/core/net_namespace.c:407 net_drop_ns net/core/net_namespace.c:406 [inline] cleanup_net+0x538/0x960 net/core/net_namespace.c:569 process_one_work+0x98e/0x1790 kernel/workqueue.c:2269 worker_thread+0x98/0xe40 kernel/workqueue.c:2415 kthread+0x357/0x430 kernel/kthread.c:253 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 The buggy address belongs to the object at ffff88806e040140 which belongs to the cache net_namespace of size 8512 The buggy address is located 4 bytes inside of 8512-byte region [ffff88806e040140, ffff88806e042280) The buggy address belongs to the page: page:ffffea0001b81000 count:1 mapcount:0 mapping:ffff88821bc45e00 index:0x0 compound_mapcount: 0 flags: 0x1fffc0000010200(slab|head) raw: 01fffc0000010200 ffffea000219f908 ffffea0001ac4508 ffff88821bc45e00 raw: 0000000000000000 ffff88806e040140 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88806e040000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88806e040080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88806e040100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ^ ffff88806e040180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806e040200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================