linux/net/tipc
Jon Maloy c3317f4db8 tipc: fix unbalanced reference counter
When a topology subscription is created, we may encounter (or KASAN
may provoke) a failure to create a corresponding service instance in
the binding table. Instead of letting the tipc_nametbl_subscribe()
report the failure back to the caller, the function just makes a warning
printout and returns, without incrementing the subscription reference
counter as expected by the caller.

This makes the caller believe that the subscription was successful, so
it will at a later moment try to unsubscribe the item. This involves
a sub_put() call. Since the reference counter never was incremented
in the first place, we get a premature delete of the subscription item,
followed by a "use-after-free" warning.

We fix this by adding a return value to tipc_nametbl_subscribe() and
make the caller aware of the failure to subscribe.

This bug seems to always have been around, but this fix only applies
back to the commit shown below. Given the low risk of this happening
we believe this to be sufficient.

Fixes: commit 218527fe27 ("tipc: replace name table service range
array with rb tree")
Reported-by: syzbot+aa245f26d42b8305d157@syzkaller.appspotmail.com

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-04-12 21:46:10 -04:00
..
addr.c tipc: handle collisions of 32-bit node address hash values 2018-03-23 13:12:18 -04:00
addr.h tipc: add 128-bit node identifier 2018-03-23 13:12:18 -04:00
bcast.c
bcast.h
bearer.c tipc: obtain node identity from interface by default 2018-03-23 13:12:18 -04:00
bearer.h tipc: some cleanups in the file discover.c 2018-03-23 13:12:17 -04:00
core.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
core.h tipc: replace name table service range array with rb tree 2018-03-31 22:19:52 -04:00
diag.c tipc: use the right skb in tipc_sk_fill_sock_diag() 2018-04-08 12:34:29 -04:00
discover.c tipc: tipc_disc_addr_trial_msg() can be static 2018-03-25 21:21:43 -04:00
discover.h tipc: some cleanups in the file discover.c 2018-03-23 13:12:17 -04:00
eth_media.c
group.c
group.h
ib_media.c
Kconfig tipc: implement socket diagnostics for AF_TIPC 2018-03-22 14:43:35 -04:00
link.c tipc: avoid possible string overflow 2018-03-31 22:19:52 -04:00
link.h tipc: handle collisions of 32-bit node address hash values 2018-03-23 13:12:18 -04:00
Makefile tipc: implement socket diagnostics for AF_TIPC 2018-03-22 14:43:35 -04:00
monitor.c
monitor.h
msg.c tipc: obsolete TIPC_ZONE_SCOPE 2018-03-17 17:11:46 -04:00
msg.h tipc: handle collisions of 32-bit node address hash values 2018-03-23 13:12:18 -04:00
name_distr.c tipc: permit overlapping service ranges in name table 2018-03-31 22:19:52 -04:00
name_distr.h tipc: permit overlapping service ranges in name table 2018-03-31 22:19:52 -04:00
name_table.c tipc: fix unbalanced reference counter 2018-04-12 21:46:10 -04:00
name_table.h tipc: fix unbalanced reference counter 2018-04-12 21:46:10 -04:00
net.c tipc: permit overlapping service ranges in name table 2018-03-31 22:19:52 -04:00
net.h tipc: obtain node identity from interface by default 2018-03-23 13:12:18 -04:00
netlink.c
netlink.h
netlink_compat.c
node.c tipc: permit overlapping service ranges in name table 2018-03-31 22:19:52 -04:00
node.h tipc: handle collisions of 32-bit node address hash values 2018-03-23 13:12:18 -04:00
socket.c tipc: use the right skb in tipc_sk_fill_sock_diag() 2018-04-08 12:34:29 -04:00
socket.h tipc: use the right skb in tipc_sk_fill_sock_diag() 2018-04-08 12:34:29 -04:00
subscr.c tipc: fix unbalanced reference counter 2018-04-12 21:46:10 -04:00
subscr.h tipc: replace name table service range array with rb tree 2018-03-31 22:19:52 -04:00
sysctl.c
topsrv.c
topsrv.h
udp_media.c tipc: fix error handling in tipc_udp_enable() 2018-03-27 10:50:02 -04:00
udp_media.h