============================= WARNING: suspicious RCU usage 4.15.0+ #307 Not tainted ----------------------------- ./include/linux/rcupdate.h:302 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by syz-executor2/14842: #0: (rcu_read_lock){....}, at: [<000000004fed5a18>] __rds_conn_create+0xe46/0x1b50 net/rds/connection.c:218 stack backtrace: CPU: 0 PID: 14842 Comm: syz-executor2 Not tainted 4.15.0+ #307 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 lockdep_rcu_suspicious+0x123/0x170 kernel/locking/lockdep.c:4592 rcu_preempt_sleep_check include/linux/rcupdate.h:301 [inline] ___might_sleep+0x385/0x470 kernel/sched/core.c:6093 __might_sleep+0x95/0x190 kernel/sched/core.c:6081 slab_pre_alloc_hook mm/slab.h:420 [inline] slab_alloc mm/slab.c:3365 [inline] kmem_cache_alloc+0x2a2/0x760 mm/slab.c:3539 rds_tcp_conn_alloc+0xa7/0x4e0 net/rds/tcp.c:296 __rds_conn_create+0x112f/0x1b50 net/rds/connection.c:227 rds_conn_create_outgoing+0x3f/0x50 net/rds/connection.c:309 rds_sendmsg+0xda3/0x2390 net/rds/send.c:1126 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 SYSC_sendto+0x361/0x5c0 net/socket.c:1747 SyS_sendto+0x40/0x50 net/socket.c:1715 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x453a59 RSP: 002b:00007f1d987ddc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f1d987de6d4 RCX: 0000000000453a59 RDX: 0000000000000000 RSI: 0000000020fc2000 RDI: 0000000000000014 RBP: 000000000071bea0 R08: 000000002069affb R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000004b9 R14: 00000000006f71f8 R15: 0000000000000000 BUG: sleeping function called from invalid context at mm/slab.h:420 in_atomic(): 1, irqs_disabled(): 0, pid: 14842, name: syz-executor2 1 lock held by syz-executor2/14842: #0: (rcu_read_lock){....}, at: [<000000004fed5a18>] __rds_conn_create+0xe46/0x1b50 net/rds/connection.c:218 CPU: 0 PID: 14842 Comm: syz-executor2 Not tainted 4.15.0+ #307 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 ___might_sleep+0x2b2/0x470 kernel/sched/core.c:6128 __might_sleep+0x95/0x190 kernel/sched/core.c:6081 slab_pre_alloc_hook mm/slab.h:420 [inline] slab_alloc mm/slab.c:3365 [inline] kmem_cache_alloc+0x2a2/0x760 mm/slab.c:3539 rds_tcp_conn_alloc+0xa7/0x4e0 net/rds/tcp.c:296 __rds_conn_create+0x112f/0x1b50 net/rds/connection.c:227 rds_conn_create_outgoing+0x3f/0x50 net/rds/connection.c:309 rds_sendmsg+0xda3/0x2390 net/rds/send.c:1126 sock_sendmsg_nosec net/socket.c:630 [inline] sock_sendmsg+0xca/0x110 net/socket.c:640 SYSC_sendto+0x361/0x5c0 net/socket.c:1747 SyS_sendto+0x40/0x50 net/socket.c:1715 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x453a59 RSP: 002b:00007f1d987ddc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f1d987de6d4 RCX: 0000000000453a59 RDX: 0000000000000000 RSI: 0000000020fc2000 RDI: 0000000000000014 RBP: 000000000071bea0 R08: 000000002069affb R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000004b9 R14: 00000000006f71f8 R15: 0000000000000000 audit: type=1400 audit(1518262211.224:31): avc: denied { ipc_lock } for pid=15577 comm="syz-executor6" capability=14 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tclass=cap_userns permissive=1 capability: warning: `syz-executor7' uses 32-bit capabilities (legacy support in use) FAULT_FLAG_ALLOW_RETRY missing 30 CPU: 1 PID: 17007 Comm: syz-executor1 Tainted: G W 4.15.0+ #307 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 handle_userfault+0xbd9/0x2500 fs/userfaultfd.c:430 do_anonymous_page mm/memory.c:3163 [inline] handle_pte_fault mm/memory.c:3977 [inline] __handle_mm_fault+0x32a3/0x3ce0 mm/memory.c:4103 handle_mm_fault+0x35c/0x970 mm/memory.c:4140 __do_page_fault+0x5c9/0xc90 arch/x86/mm/fault.c:1426 do_page_fault+0xee/0x730 arch/x86/mm/fault.c:1501 page_fault+0x2c/0x60 arch/x86/entry/entry_64.S:1152 RIP: 0010:fault_in_pages_readable arch/x86/include/asm/smap.h:58 [inline] RIP: 0010:iov_iter_fault_in_readable+0x1aa/0x420 lib/iov_iter.c:421 RSP: 0018:ffff8801b208f7e0 EFLAGS: 00010246 RAX: 0000000000010000 RBX: 0000000020011fd2 RCX: ffffffff825c27e1 RDX: 000000000000010f RSI: ffffc90003949000 RDI: ffff8801b208fbe0 RBP: ffff8801b208f8c0 R08: 0000000000000000 R09: 1ffff10036411ea8 R10: ffff8801b208f710 R11: 0000000000000003 R12: 1ffff10036411eff R13: ffff8801b208f898 R14: 0000000000000000 R15: ffff8801b208fbd8 generic_perform_write+0x200/0x600 mm/filemap.c:3128 __generic_file_write_iter+0x366/0x5b0 mm/filemap.c:3263 generic_file_write_iter+0x399/0x790 mm/filemap.c:3291 call_write_iter include/linux/fs.h:1781 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x453a59 RSP: 002b:00007f7e1ffafc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7e1ffb06d4 RCX: 0000000000453a59 RDX: 0000000000000030 RSI: 0000000020011fd2 RDI: 0000000000000014 RBP: 000000000071bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000065f R14: 00000000006f9988 R15: 0000000000000000 FAULT_FLAG_ALLOW_RETRY missing 30 CPU: 1 PID: 17046 Comm: syz-executor1 Tainted: G W 4.15.0+ #307 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 handle_userfault+0xbd9/0x2500 fs/userfaultfd.c:430 do_anonymous_page mm/memory.c:3163 [inline] handle_pte_fault mm/memory.c:3977 [inline] __handle_mm_fault+0x32a3/0x3ce0 mm/memory.c:4103 handle_mm_fault+0x35c/0x970 mm/memory.c:4140 __do_page_fault+0x5c9/0xc90 arch/x86/mm/fault.c:1426 do_page_fault+0xee/0x730 arch/x86/mm/fault.c:1501 page_fault+0x2c/0x60 arch/x86/entry/entry_64.S:1152 RIP: 0010:fault_in_pages_readable arch/x86/include/asm/smap.h:58 [inline] RIP: 0010:iov_iter_fault_in_readable+0x1aa/0x420 lib/iov_iter.c:421 RSP: 0018:ffff8801c4c077e0 EFLAGS: 00010246 RAX: 0000000000010000 RBX: 0000000020011fd2 RCX: ffffffff825c27e1 RDX: 000000000000010f RSI: ffffc90003949000 RDI: ffff8801c4c07be0 RBP: ffff8801c4c078c0 R08: 0000000000000000 R09: 1ffff10038980ea8 R10: ffff8801c4c07710 R11: 0000000000000003 R12: 1ffff10038980eff R13: ffff8801c4c07898 R14: 0000000000000000 R15: ffff8801c4c07bd8 generic_perform_write+0x200/0x600 mm/filemap.c:3128 __generic_file_write_iter+0x366/0x5b0 mm/filemap.c:3263 generic_file_write_iter+0x399/0x790 mm/filemap.c:3291 call_write_iter include/linux/fs.h:1781 [inline] new_sync_write fs/read_write.c:469 [inline] __vfs_write+0x684/0x970 fs/read_write.c:482 vfs_write+0x189/0x510 fs/read_write.c:544 SYSC_write fs/read_write.c:589 [inline] SyS_write+0xef/0x220 fs/read_write.c:581 do_syscall_64+0x282/0x940 arch/x86/entry/common.c:287 entry_SYSCALL_64_after_hwframe+0x26/0x9b RIP: 0033:0x453a59 RSP: 002b:00007f7e1ffafc68 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007f7e1ffb06d4 RCX: 0000000000453a59 RDX: 0000000000000030 RSI: 0000000020011fd2 RDI: 0000000000000014 RBP: 000000000071bea0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 000000000000065f R14: 00000000006f9988 R15: 0000000000000000 FAULT_FLAG_ALLOW_RETRY missing 30 CPU: 0 PID: 17083 Comm: syz-executor1 Tainted: G W 4.15.0+ #307 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:17 [inline] dump_stack+0x194/0x257 lib/dump_stack.c:53 handle_userfault+0xbd9/0x2500 fs/userfaultfd.c:430