kernel/net/tipc/core.c, branch linux-5.1.y

tipc: change to use register_pernet_device

2019-07-03T11:13:42Z

[ Upstream commit c492d4c74dd3f87559883ffa0f94a8f1ae3fe5f5 ] This patch is to fix a dst defcnt leak, which can be reproduced by doing: # ip net a c; ip net a s; modprobe tipc # ip net e s ip l a n eth1 type veth peer n eth1 netns c # ip net e c ip l s lo up; ip net e c ip l s eth1 up # ip net e s ip l s lo up; ip net e s ip l s eth1 up # ip net e c ip a a 1.1.1.2/8 dev eth1 # ip net e s ip a a 1.1.1.1/8 dev eth1 # ip net e c tipc b e m udp n u1 localip 1.1.1.2 # ip net e s tipc b e m udp n u1 localip 1.1.1.1 # ip net d c; ip net d s; rmmod tipc and it will get stuck and keep logging the error: unregister_netdevice: waiting for lo to become free. Usage count = 1 The cause is that a dst is held by the udp sock's sk_rx_dst set on udp rx path with udp_early_demux == 1, and this dst (eventually holding lo dev) can't be released as bearer's removal in tipc pernet .exit happens after lo dev's removal, default_device pernet .exit. "There are two distinct types of pernet_operations recognized: subsys and device. At creation all subsys init functions are called before device init functions, and at destruction all device exit functions are called before subsys exit function." So by calling register_pernet_device instead to register tipc_net_ops, the pernet .exit() will be invoked earlier than loopback dev's removal when a netns is being destroyed, as fou/gue does. Note that vxlan and geneve udp tunnels don't have this issue, as the udp sock is released in their device ndo_stop(). This fix is also necessary for tipc dst_cache, which will hold dsts on tx path and I will introduce in my next patch. Reported-by: Li Shuang Signed-off-by: Xin Long Acked-by: Jon Maloy Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tipc: fix modprobe tipc failed after switch order of device registration

2019-06-04T05:59:45Z

commit 526f5b851a96566803ee4bee60d0a34df56c77f8 upstream. Error message printed: modprobe: ERROR: could not insert 'tipc': Address family not supported by protocol. when modprobe tipc after the following patch: switch order of device registration, commit 7e27e8d6130c ("tipc: switch order of device registration to fix a crash") Because sock_create_kern(net, AF_TIPC, ...) called by tipc_topsrv_create_listener() in the initialization process of tipc_init_net(), so tipc_socket_init() must be execute before that. Meanwhile, tipc_net_id need to be initialized when sock_create() called, and tipc_socket_init() is no need to be called for each namespace. I add a variable tipc_topsrv_net_ops, and split the register_pernet_subsys() of tipc into two parts, and split tipc_socket_init() with initialization of pernet params. By the way, I fixed resources rollback error when tipc_bcast_init() failed in tipc_init_net(). Fixes: 7e27e8d6130c ("tipc: switch order of device registration to fix a crash") Signed-off-by: Junwei Hu Reported-by: Wang Wang Reported-by: syzbot+1e8114b61079bfe9cbc5@syzkaller.appspotmail.com Reviewed-by: Kang Zhou Reviewed-by: Suanming Mou Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Revert "tipc: fix modprobe tipc failed after switch order of device registration"

2019-06-04T05:59:45Z

commit 5593530e56943182ebb6d81eca8a3be6db6dbba4 upstream. This reverts commit 532b0f7ece4cb2ffd24dc723ddf55242d1188e5e. More revisions coming up. Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tipc: fix modprobe tipc failed after switch order of device registration

2019-05-25T16:16:14Z

[ Upstream commit 532b0f7ece4cb2ffd24dc723ddf55242d1188e5e ] Error message printed: modprobe: ERROR: could not insert 'tipc': Address family not supported by protocol. when modprobe tipc after the following patch: switch order of device registration, commit 7e27e8d6130c ("tipc: switch order of device registration to fix a crash") Because sock_create_kern(net, AF_TIPC, ...) is called by tipc_topsrv_create_listener() in the initialization process of tipc_net_ops, tipc_socket_init() must be execute before that. I move tipc_socket_init() into function tipc_init_net(). Fixes: 7e27e8d6130c ("tipc: switch order of device registration to fix a crash") Signed-off-by: Junwei Hu Reported-by: Wang Wang Reviewed-by: Kang Zhou Reviewed-by: Suanming Mou Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tipc: switch order of device registration to fix a crash

2019-05-25T16:16:14Z

[ Upstream commit 7e27e8d6130c5e88fac9ddec4249f7f2337fe7f8 ] When tipc is loaded while many processes try to create a TIPC socket, a crash occurs: PANIC: Unable to handle kernel paging request at virtual address "dfff20000000021d" pc : tipc_sk_create+0x374/0x1180 [tipc] lr : tipc_sk_create+0x374/0x1180 [tipc] Exception class = DABT (current EL), IL = 32 bits Call trace: tipc_sk_create+0x374/0x1180 [tipc] __sock_create+0x1cc/0x408 __sys_socket+0xec/0x1f0 __arm64_sys_socket+0x74/0xa8 ... This is due to race between sock_create and unfinished register_pernet_device. tipc_sk_insert tries to do "net_generic(net, tipc_net_id)". but tipc_net_id is not initialized yet. So switch the order of the two to close the race. This can be reproduced with multiple processes doing socket(AF_TIPC, ...) and one process doing module removal. Fixes: a62fbccecd62 ("tipc: make subscriber server support net namespace") Signed-off-by: Junwei Hu Reported-by: Wang Wang Reviewed-by: Xiaogang Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: Drop pernet_operations::async

2018-03-27T17:18:09Z

Synchronous pernet_operations are not allowed anymore. All are asynchronous. So, drop the structure member. Signed-off-by: Kirill Tkhai Signed-off-by: David S. Miller

tipc: handle collisions of 32-bit node address hash values

2018-03-23T17:12:18Z

When a 32-bit node address is generated from a 128-bit identifier, there is a risk of collisions which must be discovered and handled. We do this as follows: - We don't apply the generated address immediately to the node, but do instead initiate a 1 sec trial period to allow other cluster members to discover and handle such collisions. - During the trial period the node periodically sends out a new type of message, DSC_TRIAL_MSG, using broadcast or emulated broadcast, to all the other nodes in the cluster. - When a node is receiving such a message, it must check that the presented 32-bit identifier either is unused, or was used by the very same peer in a previous session. In both cases it accepts the request by not responding to it. - If it finds that the same node has been up before using a different address, it responds with a DSC_TRIAL_FAIL_MSG containing that address. - If it finds that the address has already been taken by some other node, it generates a new, unused address and returns it to the requester. - During the trial period the requesting node must always be prepared to accept a failure message, i.e., a message where a peer suggests a different (or equal) address to the one tried. In those cases it must apply the suggested value as trial address and restart the trial period. This algorithm ensures that in the vast majority of cases a node will have the same address before and after a reboot. If a legacy user configures the address explicitly, there will be no trial period and messages, so this protocol addition is completely backwards compatible. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

tipc: add 128-bit node identifier

2018-03-23T17:12:18Z

We add a 128-bit node identity, as an alternative to the currently used 32-bit node address. For the sake of compatibility and to minimize message header changes we retain the existing 32-bit address field. When not set explicitly by the user, this field will be filled with a hash value generated from the much longer node identity, and be used as a shorthand value for the latter. We permit either the address or the identity to be set by configuration, but not both, so when the address value is set by a legacy user the corresponding 128-bit node identity is generated based on the that value. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller

net: Convert tipc_net_ops

2018-03-13T15:24:56Z

TIPC looks concentrated in itself, and other pernet_operations seem not touching its entities. tipc_net_ops look pernet-divided, and they should be safe to be executed in parallel for several net the same time. Signed-off-by: Kirill Tkhai Signed-off-by: David S. Miller

netns: make struct pernet_operations::id unsigned int

2016-11-18T15:59:15Z

Make struct pernet_operations::id unsigned. There are 2 reasons to do so: 1) This field is really an index into an zero based array and thus is unsigned entity. Using negative value is out-of-bound access by definition. 2) On x86_64 unsigned 32-bit data which are mixed with pointers via array indexing or offsets added or subtracted to pointers are preffered to signed 32-bit data. "int" being used as an array index needs to be sign-extended to 64-bit before being used. void f(long *p, int i) { g(p[i]); } roughly translates to movsx rsi, esi mov rdi, [rsi+...] call g MOVSX is 3 byte instruction which isn't necessary if the variable is unsigned because x86_64 is zero extending by default. Now, there is net_generic() function which, you guessed it right, uses "int" as an array index: static inline void *net_generic(const struct net *net, int id) { ... ptr = ng->ptr[id - 1]; ... } And this function is used a lot, so those sign extensions add up. Patch snipes ~1730 bytes on allyesconfig kernel (without all junk messing with code generation): add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) Unfortunately some functions actually grow bigger. This is a semmingly random artefact of code generation with register allocator being used differently. gcc decides that some variable needs to live in new r8+ registers and every access now requires REX prefix. Or it is shifted into r12, so [r12+0] addressing mode has to be used which is longer than [r8] However, overall balance is in negative direction: add/remove: 0/0 grow/shrink: 70/598 up/down: 396/-2126 (-1730) function old new delta nfsd4_lock 3886 3959 +73 tipc_link_build_proto_msg 1096 1140 +44 mac80211_hwsim_new_radio 2776 2808 +32 tipc_mon_rcv 1032 1058 +26 svcauth_gss_legacy_init 1413 1429 +16 tipc_bcbase_select_primary 379 392 +13 nfsd4_exchange_id 1247 1260 +13 nfsd4_setclientid_confirm 782 793 +11 ... put_client_renew_locked 494 480 -14 ip_set_sockfn_get 730 716 -14 geneve_sock_add 829 813 -16 nfsd4_sequence_done 721 703 -18 nlmclnt_lookup_host 708 686 -22 nfsd4_lockt 1085 1063 -22 nfs_get_client 1077 1050 -27 tcf_bpf_init 1106 1076 -30 nfsd4_encode_fattr 5997 5930 -67 Total: Before=154856051, After=154854321, chg -0.00% Signed-off-by: Alexey Dobriyan Signed-off-by: David S. Miller