linux-stable.git/net/smc, branch v5.6

net/smc: cancel event worker during device removal

2020-03-10T22:40:33+00:00

During IB device removal, cancel the event worker before the device
structure is freed.

Fixes: a4cf0443c414 ("smc: introduce SMC as an IB-client")
Reported-by: syzbot+b297c6825752e7a07272@syzkaller.appspotmail.com
Signed-off-by: Karsten Graul 
Reviewed-by: Ursula Braun 
Reviewed-by: Leon Romanovsky 
Signed-off-by: David S. Miller

net/smc: check for valid ib_client_data

2020-02-27T04:56:25+00:00

In smc_ib_remove_dev() check if the provided ib device was actually
initialized for SMC before.

Reported-by: syzbot+84484ccebdd4e5451d91@syzkaller.appspotmail.com
Fixes: a4cf0443c414 ("smc: introduce SMC as an IB-client")
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

net/smc: fix cleanup for linkgroup setup failures

2020-02-27T04:18:07+00:00

If an SMC connection to a certain peer is setup the first time,
a new linkgroup is created. In case of setup failures, such a
linkgroup is unusable and should disappear. As a first step the
linkgroup is removed from the linkgroup list in smc_lgr_forget().

There are 2 problems:
smc_listen_decline() might be called before linkgroup creation
resulting in a crash due to calling smc_lgr_forget() with
parameter NULL.
If a setup failure occurs after linkgroup creation, the connection
is never unregistered from the linkgroup, preventing linkgroup
freeing.

This patch introduces an enhanced smc_lgr_cleanup_early() function
which
* contains a linkgroup check for early smc_listen_decline()
  invocations
* invokes smc_conn_free() to guarantee unregistering of the
  connection.
* schedules fast linkgroup removal of the unusable linkgroup

And the unused function smcd_conn_free() is removed from smc_core.h.

Fixes: 3b2dec2603d5b ("net/smc: restructure client and server code in af_smc")
Fixes: 2a0674fffb6bc ("net/smc: improve abnormal termination of link groups")
Signed-off-by: Ursula Braun 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

net/smc: no peer ID in CLC decline for SMCD

2020-02-14T15:09:36+00:00

Just SMCR requires a CLC Peer ID, but not SMCD. The field should be
zero for SMCD.

Fixes: c758dfddc1b5 ("net/smc: add SMC-D support in CLC messages")
Signed-off-by: Ursula Braun 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

net/smc: transfer fasync_list in case of fallback

2020-02-14T15:09:36+00:00

SMC does not work together with FASTOPEN. If sendmsg() is called with
flag MSG_FASTOPEN in SMC_INIT state, the SMC-socket switches to
fallback mode. To handle the previous ioctl FIOASYNC call correctly
in this case, it is necessary to transfer the socket wait queue
fasync_list to the internal TCP socket.

Reported-by: syzbot+4b1fe8105f8044a26162@syzkaller.appspotmail.com
Fixes: ee9dfbef02d18 ("net/smc: handle sockopts forcing fallback")
Signed-off-by: Ursula Braun 
Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

net/smc: fix leak of kernel memory to user space

2020-02-12T01:04:42+00:00

As nlmsg_put() does not clear the memory that is reserved,
it this the caller responsability to make sure all of this
memory will be written, in order to not reveal prior content.

While we are at it, we can provide the socket cookie even
if clsock is not set.

syzbot reported :

BUG: KMSAN: uninit-value in __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
BUG: KMSAN: uninit-value in __fswab32 include/uapi/linux/swab.h:59 [inline]
BUG: KMSAN: uninit-value in __swab32p include/uapi/linux/swab.h:179 [inline]
BUG: KMSAN: uninit-value in __be32_to_cpup include/uapi/linux/byteorder/little_endian.h:82 [inline]
BUG: KMSAN: uninit-value in get_unaligned_be32 include/linux/unaligned/access_ok.h:30 [inline]
BUG: KMSAN: uninit-value in ____bpf_skb_load_helper_32 net/core/filter.c:240 [inline]
BUG: KMSAN: uninit-value in ____bpf_skb_load_helper_32_no_cache net/core/filter.c:255 [inline]
BUG: KMSAN: uninit-value in bpf_skb_load_helper_32_no_cache+0x14a/0x390 net/core/filter.c:252
CPU: 1 PID: 5262 Comm: syz-executor.5 Not tainted 5.5.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
 __fswab32 include/uapi/linux/swab.h:59 [inline]
 __swab32p include/uapi/linux/swab.h:179 [inline]
 __be32_to_cpup include/uapi/linux/byteorder/little_endian.h:82 [inline]
 get_unaligned_be32 include/linux/unaligned/access_ok.h:30 [inline]
 ____bpf_skb_load_helper_32 net/core/filter.c:240 [inline]
 ____bpf_skb_load_helper_32_no_cache net/core/filter.c:255 [inline]
 bpf_skb_load_helper_32_no_cache+0x14a/0x390 net/core/filter.c:252

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_kmalloc_large+0x73/0xc0 mm/kmsan/kmsan_hooks.c:128
 kmalloc_large_node_hook mm/slub.c:1406 [inline]
 kmalloc_large_node+0x282/0x2c0 mm/slub.c:3841
 __kmalloc_node_track_caller+0x44b/0x1200 mm/slub.c:4368
 __kmalloc_reserve net/core/skbuff.c:141 [inline]
 __alloc_skb+0x2fd/0xac0 net/core/skbuff.c:209
 alloc_skb include/linux/skbuff.h:1049 [inline]
 netlink_dump+0x44b/0x1ab0 net/netlink/af_netlink.c:2224
 __netlink_dump_start+0xbb2/0xcf0 net/netlink/af_netlink.c:2352
 netlink_dump_start include/linux/netlink.h:233 [inline]
 smc_diag_handler_dump+0x2ba/0x300 net/smc/smc_diag.c:242
 sock_diag_rcv_msg+0x211/0x610 net/core/sock_diag.c:256
 netlink_rcv_skb+0x451/0x650 net/netlink/af_netlink.c:2477
 sock_diag_rcv+0x63/0x80 net/core/sock_diag.c:275
 netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
 netlink_unicast+0xf9e/0x1100 net/netlink/af_netlink.c:1328
 netlink_sendmsg+0x1248/0x14d0 net/netlink/af_netlink.c:1917
 sock_sendmsg_nosec net/socket.c:639 [inline]
 sock_sendmsg net/socket.c:659 [inline]
 kernel_sendmsg+0x433/0x440 net/socket.c:679
 sock_no_sendpage+0x235/0x300 net/core/sock.c:2740
 kernel_sendpage net/socket.c:3776 [inline]
 sock_sendpage+0x1e1/0x2c0 net/socket.c:937
 pipe_to_sendpage+0x38c/0x4c0 fs/splice.c:458
 splice_from_pipe_feed fs/splice.c:512 [inline]
 __splice_from_pipe+0x539/0xed0 fs/splice.c:636
 splice_from_pipe fs/splice.c:671 [inline]
 generic_splice_sendpage+0x1d5/0x2d0 fs/splice.c:844
 do_splice_from fs/splice.c:863 [inline]
 do_splice fs/splice.c:1170 [inline]
 __do_sys_splice fs/splice.c:1447 [inline]
 __se_sys_splice+0x2380/0x3350 fs/splice.c:1427
 __x64_sys_splice+0x6e/0x90 fs/splice.c:1427
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: f16a7dd5cf27 ("smc: netlink interface for SMC sockets")
Signed-off-by: Eric Dumazet 
Cc: Ursula Braun 
Signed-off-by: David S. Miller

net/smc: allow unprivileged users to read pnet table

2020-01-21T10:39:56+00:00

The current flags of the SMC_PNET_GET command only allow privileged
users to retrieve entries from the pnet table via netlink. The content
of the pnet table may be useful for all users though, e.g., for
debugging smc connection problems.

This patch removes the GENL_ADMIN_PERM flag so that unprivileged users
can read the pnet table.

Signed-off-by: Hans Wippel 
Signed-off-by: David S. Miller

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

2019-12-22T23:15:05+00:00

Mere overlapping changes in the conflicts here.

Signed-off-by: David S. Miller

net/smc: unregister ib devices in reboot_event

2019-12-21T05:31:19+00:00

In the reboot_event handler, unregister the ib devices and enable
the IB layer to release the devices before the reboot.

Fixes: a33a803cfe64 ("net/smc: guarantee removal of link groups in reboot")
Signed-off-by: Karsten Graul 
Reviewed-by: Ursula Braun 
Signed-off-by: David S. Miller

net/smc: add fallback check to connect()

2019-12-15T19:10:30+00:00

FASTOPEN setsockopt() or sendmsg() may switch the SMC socket to fallback
mode. Once fallback mode is active, the native TCP socket functions are
called. Nevertheless there is a small race window, when FASTOPEN
setsockopt/sendmsg runs in parallel to a connect(), and switch the
socket into fallback mode before connect() takes the sock lock.
Make sure the SMC-specific connect setup is omitted in this case.

This way a syzbot-reported refcount problem is fixed, triggered by
different threads running non-blocking connect() and FASTOPEN_KEY
setsockopt.

Reported-by: syzbot+96d3f9ff6a86d37e44c8@syzkaller.appspotmail.com
Fixes: 6d6dd528d5af ("net/smc: fix refcount non-blocking connect() -part 2")
Signed-off-by: Ursula Braun 
Signed-off-by: Karsten Graul 
Signed-off-by: Jakub Kicinski