kernel/linux.git/net/tipc/core.c, branch v6.6.132

tipc: fix use-after-free Read in tipc_named_reinit

2022-06-17T10:39:10+00:00

syzbot found the following issue on: ================================================================== BUG: KASAN: use-after-free in tipc_named_reinit+0x94f/0x9b0 net/tipc/name_distr.c:413 Read of size 8 at addr ffff88805299a000 by task kworker/1:9/23764 CPU: 1 PID: 23764 Comm: kworker/1:9 Not tainted 5.18.0-rc4-syzkaller-00878-g17d49e6e8012 #0 Hardware name: Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events tipc_net_finalize_work Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 tipc_named_reinit+0x94f/0x9b0 net/tipc/name_distr.c:413 tipc_net_finalize+0x234/0x3d0 net/tipc/net.c:138 process_one_work+0x996/0x1610 kernel/workqueue.c:2289 worker_thread+0x665/0x1080 kernel/workqueue.c:2436 kthread+0x2e9/0x3a0 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 [...] ================================================================== In the commit d966ddcc3821 ("tipc: fix a deadlock when flushing scheduled work"), the cancel_work_sync() function just to make sure ONLY the work tipc_net_finalize_work() is executing/pending on any CPU completed before tipc namespace is destroyed through tipc_exit_net(). But this function is not guaranteed the work is the last queued. So, the destroyed instance may be accessed in the work which will try to enqueue later. In order to completely fix, we re-order the calling of cancel_work_sync() to make sure the work tipc_net_finalize_work() was last queued and it must be completed by calling cancel_work_sync(). Reported-by: syzbot+47af19f3307fc9c5c82e@syzkaller.appspotmail.com Fixes: d966ddcc3821 ("tipc: fix a deadlock when flushing scheduled work") Acked-by: Jon Maloy Signed-off-by: Ying Xue Signed-off-by: Hoang Le Signed-off-by: David S. Miller

tipc: simplify the finalize work queue

2021-05-18T20:22:09+00:00

This patch is to use "struct work_struct" for the finalize work queue instead of "struct tipc_net_work", as it can get the "net" and "addr" from tipc_net's other members and there is no need to add extra net and addr in tipc_net by defining "struct tipc_net_work". Note that it's safe to get net from tn->bcl as bcl is always released after the finalize work queue is done. Signed-off-by: Xin Long Acked-by: Jon Maloy Signed-off-by: David S. Miller

tipc: wait and exit until all work queues are done

2021-05-17T21:07:48+00:00

On some host, a crash could be triggered simply by repeating these commands several times: # modprobe tipc # tipc bearer enable media udp name UDP1 localip 127.0.0.1 # rmmod tipc [] BUG: unable to handle kernel paging request at ffffffffc096bb00 [] Workqueue: events 0xffffffffc096bb00 [] Call Trace: [] ? process_one_work+0x1a7/0x360 [] ? worker_thread+0x30/0x390 [] ? create_worker+0x1a0/0x1a0 [] ? kthread+0x116/0x130 [] ? kthread_flush_work_fn+0x10/0x10 [] ? ret_from_fork+0x35/0x40 When removing the TIPC module, the UDP tunnel sock will be delayed to release in a work queue as sock_release() can't be done in rtnl_lock(). If the work queue is schedule to run after the TIPC module is removed, kernel will crash as the work queue function cleanup_beareri() code no longer exists when trying to invoke it. To fix it, this patch introduce a member wq_count in tipc_net to track the numbers of work queues in schedule, and wait and exit until all work queues are done in tipc_exit_net(). Fixes: d0f91938bede ("tipc: add ip/udp media type") Reported-by: Shuang Li Signed-off-by: Xin Long Acked-by: Jon Maloy Signed-off-by: David S. Miller

tipc: remove dead code in tipc_net and relatives

2020-10-30T20:11:47+00:00

dist_queue is no longer used since commit 37922ea4a310 ("tipc: permit overlapping service ranges in name table") Acked-by: Jon Maloy Acked-by: Ying Xue Signed-off-by: Hoang Huu Le Link: https://lore.kernel.org/r/20201028032712.31009-1-hoang.h.le@dektech.com.au Signed-off-by: Jakub Kicinski

tipc: fix a deadlock when flushing scheduled work

2020-09-07T19:08:53+00:00

In the commit fdeba99b1e58 ("tipc: fix use-after-free in tipc_bcast_get_mode"), we're trying to make sure the tipc_net_finalize_work work item finished if it enqueued. But calling flush_scheduled_work() is not just affecting above work item but either any scheduled work. This has turned out to be overkill and caused to deadlock as syzbot reported: ====================================================== WARNING: possible circular locking dependency detected 5.9.0-rc2-next-20200828-syzkaller #0 Not tainted ------------------------------------------------------ kworker/u4:6/349 is trying to acquire lock: ffff8880aa063d38 ((wq_completion)events){+.+.}-{0:0}, at: flush_workqueue+0xe1/0x13e0 kernel/workqueue.c:2777 but task is already holding lock: ffffffff8a879430 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9b/0xb10 net/core/net_namespace.c:565 [...] Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(pernet_ops_rwsem); lock(&sb->s_type->i_mutex_key#13); lock(pernet_ops_rwsem); lock((wq_completion)events); *** DEADLOCK *** [...] v1: To fix the original issue, we replace above calling by introducing a bit flag. When a namespace cleaned-up, bit flag is set to zero and: - tipc_net_finalize functionial just does return immediately. - tipc_net_finalize_work does not enqueue into the scheduled work queue. v2: Use cancel_work_sync() helper to make sure ONLY the tipc_net_finalize_work() stopped before releasing bcbase object. Reported-by: syzbot+d5aa7e0385f6a5d0f4fd@syzkaller.appspotmail.com Fixes: fdeba99b1e58 ("tipc: fix use-after-free in tipc_bcast_get_mode") Acked-by: Jon Maloy Signed-off-by: Hoang Huu Le Signed-off-by: Jakub Kicinski

tipc: fix use-after-free in tipc_bcast_get_mode

2020-08-27T13:59:42+00:00

Syzbot has reported those issues as: ================================================================== BUG: KASAN: use-after-free in tipc_bcast_get_mode+0x3ab/0x400 net/tipc/bcast.c:759 Read of size 1 at addr ffff88805e6b3571 by task kworker/0:6/3850 CPU: 0 PID: 3850 Comm: kworker/0:6 Not tainted 5.8.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events tipc_net_finalize_work Thread 1's call trace: [...] kfree+0x103/0x2c0 mm/slab.c:3757 <- bcbase releasing tipc_bcast_stop+0x1b0/0x2f0 net/tipc/bcast.c:721 tipc_exit_net+0x24/0x270 net/tipc/core.c:112 [...] Thread 2's call trace: [...] tipc_bcast_get_mode+0x3ab/0x400 net/tipc/bcast.c:759 <- bcbase has already been freed by Thread 1 tipc_node_broadcast+0x9e/0xcc0 net/tipc/node.c:1744 tipc_nametbl_publish+0x60b/0x970 net/tipc/name_table.c:752 tipc_net_finalize net/tipc/net.c:141 [inline] tipc_net_finalize+0x1fa/0x310 net/tipc/net.c:131 tipc_net_finalize_work+0x55/0x80 net/tipc/net.c:150 [...] ================================================================== BUG: KASAN: use-after-free in tipc_named_reinit+0xef/0x290 net/tipc/name_distr.c:344 Read of size 8 at addr ffff888052ab2000 by task kworker/0:13/30628 CPU: 0 PID: 30628 Comm: kworker/0:13 Not tainted 5.8.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: events tipc_net_finalize_work Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1f0/0x31e lib/dump_stack.c:118 print_address_description+0x66/0x5a0 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x132/0x1d0 mm/kasan/report.c:530 tipc_named_reinit+0xef/0x290 net/tipc/name_distr.c:344 tipc_net_finalize+0x85/0xe0 net/tipc/net.c:138 tipc_net_finalize_work+0x50/0x70 net/tipc/net.c:150 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 [...] Freed by task 14058: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0x114/0x170 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x220 mm/slab.c:3757 tipc_exit_net+0x29/0x50 net/tipc/core.c:113 ops_exit_list net/core/net_namespace.c:186 [inline] cleanup_net+0x708/0xba0 net/core/net_namespace.c:603 process_one_work+0x789/0xfc0 kernel/workqueue.c:2269 worker_thread+0xaa4/0x1460 kernel/workqueue.c:2415 kthread+0x37e/0x3a0 drivers/block/aoe/aoecmd.c:1234 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 Fix it by calling flush_scheduled_work() to make sure the tipc_net_finalize_work() stopped before releasing bcbase object. Reported-by: syzbot+6ea1f7a8df64596ef4d7@syzkaller.appspotmail.com Reported-by: syzbot+e9cc557752ab126c1b99@syzkaller.appspotmail.com Acked-by: Jon Maloy Signed-off-by: Hoang Huu Le Signed-off-by: David S. Miller

tipc: fix ordering of tipc module init and exit routine

2019-12-06T20:01:09+00:00

In order to set/get/dump, the tipc uses the generic netlink infrastructure. So, when tipc module is inserted, init function calls genl_register_family(). After genl_register_family(), set/get/dump commands are immediately allowed and these callbacks internally use the net_generic. net_generic is allocated by register_pernet_device() but this is called after genl_register_family() in the __init function. So, these callbacks would use un-initialized net_generic. Test commands: #SHELL1 while : do modprobe tipc modprobe -rv tipc done #SHELL2 while : do tipc link list done Splat looks like: [ 59.616322][ T2788] kasan: CONFIG_KASAN_INLINE enabled [ 59.617234][ T2788] kasan: GPF could be caused by NULL-ptr deref or user memory access [ 59.618398][ T2788] general protection fault: 0000 [#1] SMP DEBUG_PAGEALLOC KASAN PTI [ 59.619389][ T2788] CPU: 3 PID: 2788 Comm: tipc Not tainted 5.4.0+ #194 [ 59.620231][ T2788] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006 [ 59.621428][ T2788] RIP: 0010:tipc_bcast_get_broadcast_mode+0x131/0x310 [tipc] [ 59.622379][ T2788] Code: c7 c6 ef 8b 38 c0 65 ff 0d 84 83 c9 3f e8 d7 a5 f2 e3 48 8d bb 38 11 00 00 48 b8 00 00 00 00 [ 59.622550][ T2780] NET: Registered protocol family 30 [ 59.624627][ T2788] RSP: 0018:ffff88804b09f578 EFLAGS: 00010202 [ 59.624630][ T2788] RAX: dffffc0000000000 RBX: 0000000000000011 RCX: 000000008bc66907 [ 59.624631][ T2788] RDX: 0000000000000229 RSI: 000000004b3cf4cc RDI: 0000000000001149 [ 59.624633][ T2788] RBP: ffff88804b09f588 R08: 0000000000000003 R09: fffffbfff4fb3df1 [ 59.624635][ T2788] R10: fffffbfff50318f8 R11: ffff888066cadc18 R12: ffffffffa6cc2f40 [ 59.624637][ T2788] R13: 1ffff11009613eba R14: ffff8880662e9328 R15: ffff8880662e9328 [ 59.624639][ T2788] FS: 00007f57d8f7b740(0000) GS:ffff88806cc00000(0000) knlGS:0000000000000000 [ 59.624645][ T2788] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 59.625875][ T2780] tipc: Started in single node mode [ 59.626128][ T2788] CR2: 00007f57d887a8c0 CR3: 000000004b140002 CR4: 00000000000606e0 [ 59.633991][ T2788] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 59.635195][ T2788] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 59.636478][ T2788] Call Trace: [ 59.637025][ T2788] tipc_nl_add_bc_link+0x179/0x1470 [tipc] [ 59.638219][ T2788] ? lock_downgrade+0x6e0/0x6e0 [ 59.638923][ T2788] ? __tipc_nl_add_link+0xf90/0xf90 [tipc] [ 59.639533][ T2788] ? tipc_nl_node_dump_link+0x318/0xa50 [tipc] [ 59.640160][ T2788] ? mutex_lock_io_nested+0x1380/0x1380 [ 59.640746][ T2788] tipc_nl_node_dump_link+0x4fd/0xa50 [tipc] [ 59.641356][ T2788] ? tipc_nl_node_reset_link_stats+0x340/0x340 [tipc] [ 59.642088][ T2788] ? __skb_ext_del+0x270/0x270 [ 59.642594][ T2788] genl_lock_dumpit+0x85/0xb0 [ 59.643050][ T2788] netlink_dump+0x49c/0xed0 [ 59.643529][ T2788] ? __netlink_sendskb+0xc0/0xc0 [ 59.644044][ T2788] ? __netlink_dump_start+0x190/0x800 [ 59.644617][ T2788] ? __mutex_unlock_slowpath+0xd0/0x670 [ 59.645177][ T2788] __netlink_dump_start+0x5a0/0x800 [ 59.645692][ T2788] genl_rcv_msg+0xa75/0xe90 [ 59.646144][ T2788] ? __lock_acquire+0xdfe/0x3de0 [ 59.646692][ T2788] ? genl_family_rcv_msg_attrs_parse+0x320/0x320 [ 59.647340][ T2788] ? genl_lock_dumpit+0xb0/0xb0 [ 59.647821][ T2788] ? genl_unlock+0x20/0x20 [ 59.648290][ T2788] ? genl_parallel_done+0xe0/0xe0 [ 59.648787][ T2788] ? find_held_lock+0x39/0x1d0 [ 59.649276][ T2788] ? genl_rcv+0x15/0x40 [ 59.649722][ T2788] ? lock_contended+0xcd0/0xcd0 [ 59.650296][ T2788] netlink_rcv_skb+0x121/0x350 [ 59.650828][ T2788] ? genl_family_rcv_msg_attrs_parse+0x320/0x320 [ 59.651491][ T2788] ? netlink_ack+0x940/0x940 [ 59.651953][ T2788] ? lock_acquire+0x164/0x3b0 [ 59.652449][ T2788] genl_rcv+0x24/0x40 [ 59.652841][ T2788] netlink_unicast+0x421/0x600 [ ... ] Fixes: 7e4369057806 ("tipc: fix a slab object leak") Fixes: a62fbccecd62 ("tipc: make subscriber server support net namespace") Signed-off-by: Taehee Yoo Acked-by: Jon Maloy Signed-off-by: David S. Miller

Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net

2019-11-17T05:51:42+00:00

Lots of overlapping changes and parallel additions, stuff like that. Signed-off-by: David S. Miller

tipc: add back tipc prefix to log messages

2019-11-15T02:03:03+00:00

The tipc prefix for log messages generated by tipc was removed in commit 07f6c4bc048a ("tipc: convert tipc reference table to use generic rhashtable"). This is still a useful prefix so add it back. Signed-off-by: Matt Bennett Acked-by: Jon Maloy Signed-off-by: David S. Miller

tipc: introduce TIPC encryption & authentication

2019-11-08T22:01:59+00:00

This commit offers an option to encrypt and authenticate all messaging, including the neighbor discovery messages. The currently most advanced algorithm supported is the AEAD AES-GCM (like IPSec or TLS). All encryption/decryption is done at the bearer layer, just before leaving or after entering TIPC. Supported features: - Encryption & authentication of all TIPC messages (header + data); - Two symmetric-key modes: Cluster and Per-node; - Automatic key switching; - Key-expired revoking (sequence number wrapped); - Lock-free encryption/decryption (RCU); - Asynchronous crypto, Intel AES-NI supported; - Multiple cipher transforms; - Logs & statistics; Two key modes: - Cluster key mode: One single key is used for both TX & RX in all nodes in the cluster. - Per-node key mode: Each nodes in the cluster has one specific TX key. For RX, a node requires its peers' TX key to be able to decrypt the messages from those peers. Key setting from user-space is performed via netlink by a user program (e.g. the iproute2 'tipc' tool). Internal key state machine: Attach Align(RX) +-+ +-+ | V | V +---------+ Attach +---------+ | IDLE |---------------->| PENDING |(user = 0) +---------+ +---------+ A A Switch| A | | | | | | Free(switch/revoked) | | (Free)| +----------------------+ | |Timeout | (TX) | | |(RX) | | | | | | v | +---------+ Switch +---------+ | PASSIVE |<----------------| ACTIVE | +---------+ (RX) +---------+ (user = 1) (user >= 1) The number of TFMs is 10 by default and can be changed via the procfs 'net/tipc/max_tfms'. At this moment, as for simplicity, this file is also used to print the crypto statistics at runtime: echo 0xfff1 > /proc/sys/net/tipc/max_tfms The patch defines a new TIPC version (v7) for the encryption message (- backward compatibility as well). The message is basically encapsulated as follows: +----------------------------------------------------------+ | TIPCv7 encryption | Original TIPCv2 | Authentication | | header | packet (encrypted) | Tag | +----------------------------------------------------------+ The throughput is about ~40% for small messages (compared with non- encryption) and ~9% for large messages. With the support from hardware crypto i.e. the Intel AES-NI CPU instructions, the throughput increases upto ~85% for small messages and ~55% for large messages. By default, the new feature is inactive (i.e. no encryption) until user sets a key for TIPC. There is however also a new option - "TIPC_CRYPTO" in the kernel configuration to enable/disable the new code when needed. MAINTAINERS | add two new files 'crypto.h' & 'crypto.c' in tipc Acked-by: Ying Xue Acked-by: Jon Maloy Signed-off-by: Tuong Lien Signed-off-by: David S. Miller