====================================================== [ INFO: possible circular locking dependency detected ] 4.9.111-g03c70fe #6 Not tainted ------------------------------------------------------- syz-executor2/19401 is trying to acquire lock: (rtnl_mutex){+.+.+.}, at: [] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 but task is already holding lock: (sk_lock-AF_INET){+.+.+.}, at: [] lock_sock include/net/sock.h:1404 [inline] (sk_lock-AF_INET){+.+.+.}, at: [] do_ip_setsockopt.isra.13+0x269/0x2b10 net/ipv4/ip_sockglue.c:636 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756 lock_sock_nested+0xc6/0x120 net/core/sock.c:2511 lock_sock include/net/sock.h:1404 [inline] do_ip_setsockopt.isra.13+0x12a/0x2b10 net/ipv4/ip_sockglue.c:636 FAT-fs (loop7): bogus number of reserved sectors FAT-fs (loop7): Can't find a valid FAT filesystem ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1240 udp_setsockopt+0x4a/0x90 net/ipv4/udp.c:2091 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706 SYSC_setsockopt net/socket.c:1772 [inline] SyS_setsockopt+0x166/0x260 net/socket.c:1751 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x5d/0xdb check_prev_add kernel/locking/lockdep.c:1828 [inline] check_prevs_add kernel/locking/lockdep.c:1938 [inline] validate_chain kernel/locking/lockdep.c:2265 [inline] __lock_acquire+0x3019/0x4070 kernel/locking/lockdep.c:3345 lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756 __mutex_lock_common kernel/locking/mutex.c:521 [inline] mutex_lock_nested+0xc0/0x870 kernel/locking/mutex.c:621 rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 mrtsock_destruct+0x3b/0x1e0 net/ipv4/ipmr.c:1231 ip_ra_control+0x2c2/0x420 net/ipv4/ip_sockglue.c:360 do_ip_setsockopt.isra.13+0x15ff/0x2b10 net/ipv4/ip_sockglue.c:1137 ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1240 raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:833 sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706 SYSC_setsockopt net/socket.c:1772 [inline] SyS_setsockopt+0x166/0x260 net/socket.c:1751 do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 entry_SYSCALL_64_after_swapgs+0x5d/0xdb other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_INET); lock(rtnl_mutex); lock(sk_lock-AF_INET); lock(rtnl_mutex); *** DEADLOCK *** 1 lock held by syz-executor2/19401: #0: (sk_lock-AF_INET){+.+.+.}, at: [] lock_sock include/net/sock.h:1404 [inline] #0: (sk_lock-AF_INET){+.+.+.}, at: [] do_ip_setsockopt.isra.13+0x269/0x2b10 net/ipv4/ip_sockglue.c:636 stack backtrace: CPU: 0 PID: 19401 Comm: syz-executor2 Not tainted 4.9.111-g03c70fe #6 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 ffff8801aa6ef5f8 ffffffff81eb2729 ffffffff8559cef0 ffffffff855e7d10 ffffffff8559cef0 ffff8801a70220e8 ffff8801a7021800 ffff8801aa6ef640 ffffffff814263a4 0000000000000001 00000000a7021800 0000000000000001 Call Trace: [] __dump_stack lib/dump_stack.c:15 [inline] [] dump_stack+0xc1/0x128 lib/dump_stack.c:51 [] print_circular_bug.cold.51+0x1bd/0x27d kernel/locking/lockdep.c:1202 [] check_prev_add kernel/locking/lockdep.c:1828 [inline] [] check_prevs_add kernel/locking/lockdep.c:1938 [inline] [] validate_chain kernel/locking/lockdep.c:2265 [inline] [] __lock_acquire+0x3019/0x4070 kernel/locking/lockdep.c:3345 [] lock_acquire+0x130/0x3e0 kernel/locking/lockdep.c:3756 [] __mutex_lock_common kernel/locking/mutex.c:521 [inline] [] mutex_lock_nested+0xc0/0x870 kernel/locking/mutex.c:621 [] rtnl_lock+0x17/0x20 net/core/rtnetlink.c:70 [] mrtsock_destruct+0x3b/0x1e0 net/ipv4/ipmr.c:1231 [] ip_ra_control+0x2c2/0x420 net/ipv4/ip_sockglue.c:360 [] do_ip_setsockopt.isra.13+0x15ff/0x2b10 net/ipv4/ip_sockglue.c:1137 [] ip_setsockopt+0x3a/0xb0 net/ipv4/ip_sockglue.c:1240 [] raw_setsockopt+0xb7/0xd0 net/ipv4/raw.c:833 [] sock_common_setsockopt+0x9a/0xe0 net/core/sock.c:2706 [] SYSC_setsockopt net/socket.c:1772 [inline] [] SyS_setsockopt+0x166/0x260 net/socket.c:1751 [] do_syscall_64+0x1a6/0x490 arch/x86/entry/common.c:282 [] entry_SYSCALL_64_after_swapgs+0x5d/0xdb FAT-fs (loop7): bogus number of reserved sectors FAT-fs (loop7): Can't find a valid FAT filesystem FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem syz-executor7 (19412) used greatest stack depth: 22336 bytes left IPVS: Creating netns size=2536 id=55 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=56 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=57 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=58 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=59 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=60 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=61 IPVS: Creating netns size=2536 id=62 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=63 IPVS: Creating netns size=2536 id=64 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem IPVS: Creating netns size=2536 id=65 IPVS: Creating netns size=2536 id=66 FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem pktgen: kernel_thread() failed for cpu 0 pktgen: Cannot create thread for cpu 0 (-4) pktgen: kernel_thread() failed for cpu 1 pktgen: Cannot create thread for cpu 1 (-4) pktgen: Initialization failed for all threads pktgen: kernel_thread() failed for cpu 0 pktgen: Cannot create thread for cpu 0 (-4) pktgen: kernel_thread() failed for cpu 1 pktgen: Cannot create thread for cpu 1 (-4) pktgen: Initialization failed for all threads FAT-fs (loop6): invalid media value (0x07) FAT-fs (loop6): Can't find a valid FAT filesystem FAT-fs (loop7): invalid media value (0x07) FAT-fs (loop7): Can't find a valid FAT filesystem pktgen: kernel_thread() failed for cpu 0 pktgen: Cannot create thread for cpu 0 (-4) pktgen: kernel_thread() failed for cpu 1 pktgen: Cannot create thread for cpu 1 (-4) pktgen: Initialization failed for all threads pktgen: kernel_thread() failed for cpu 0 pktgen: Cannot create thread for cpu 0 (-4) pktgen: kernel_thread() failed for cpu 1 pktgen: Cannot create thread for cpu 1 (-4) pktgen: Initialization failed for all threads