================================================================== BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:938 [inline] BUG: KASAN: use-after-free in __mutex_lock+0x1033/0x13c0 kernel/locking/mutex.c:1103 Read of size 8 at addr ffff888077598388 by task kworker/u4:5/755 CPU: 1 PID: 755 Comm: kworker/u4:5 Not tainted 5.5.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: ib_addr process_one_req Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:639 __asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135 __mutex_lock_common kernel/locking/mutex.c:938 [inline] __mutex_lock+0x1033/0x13c0 kernel/locking/mutex.c:1103 mutex_lock_nested+0x16/0x20 kernel/locking/mutex.c:1118 addr_handler+0xaf/0x3d0 drivers/infiniband/core/cma.c:3059 process_one_req+0x106/0x680 drivers/infiniband/core/addr.c:643 process_one_work+0x9af/0x1740 kernel/workqueue.c:2264 worker_thread+0x98/0xe40 kernel/workqueue.c:2410 kthread+0x361/0x430 kernel/kthread.c:255 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352 Allocated by task 17830: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:527 kmem_cache_alloc_trace+0x158/0x790 mm/slab.c:3551 kmalloc include/linux/slab.h:556 [inline] kzalloc include/linux/slab.h:670 [inline] __rdma_create_id+0x5e/0x560 drivers/infiniband/core/cma.c:855 ucma_create_id+0x1de/0x620 drivers/infiniband/core/ucma.c:501 ucma_write+0x2d7/0x3c0 drivers/infiniband/core/ucma.c:1684 __vfs_write+0x8a/0x110 fs/read_write.c:494 vfs_write+0x268/0x5d0 fs/read_write.c:558 ksys_write+0x220/0x290 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write fs/read_write.c:620 [inline] __x64_sys_write+0x73/0xb0 fs/read_write.c:620 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 17824: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:335 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:474 kasan_slab_free+0xe/0x10 mm/kasan/common.c:483 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 rdma_destroy_id+0x75a/0xb00 drivers/infiniband/core/cma.c:1850 ucma_close+0x115/0x310 drivers/infiniband/core/ucma.c:1762 __fput+0x2ff/0x890 fs/file_table.c:280 ____fput+0x16/0x20 fs/file_table.c:313 task_work_run+0x145/0x1c0 kernel/task_work.c:113 tracehook_notify_resume include/linux/tracehook.h:188 [inline] exit_to_usermode_loop+0x316/0x380 arch/x86/entry/common.c:164 prepare_exit_to_usermode arch/x86/entry/common.c:195 [inline] syscall_return_slowpath arch/x86/entry/common.c:278 [inline] do_syscall_64+0x676/0x790 arch/x86/entry/common.c:304 entry_SYSCALL_64_after_hwframe+0x49/0xbe The buggy address belongs to the object at ffff888077598000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 904 bytes inside of 2048-byte region [ffff888077598000, ffff888077598800) The buggy address belongs to the page: page:ffffea0001dd6600 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 raw: 00fffe0000000200 ffffea0001e56e48 ffffea00025fd488 ffff8880aa400e00 raw: 0000000000000000 ffff888077598000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff888077598280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888077598300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888077598380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888077598400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888077598480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================