kernel.git/net/sctp/proc.c, branch linux-4.9.y

sctp: hold transport before accessing its asoc in sctp_transport_get_next

2018-09-15T07:42:56Z

[ Upstream commit bab1be79a5169ac748d8292b20c86d874022d7ba ] As Marcelo noticed, in sctp_transport_get_next, it is iterating over transports but then also accessing the association directly, without checking any refcnts before that, which can cause an use-after-free Read. So fix it by holding transport before accessing the association. With that, sctp_transport_hold calls can be removed in the later places. Fixes: 626d16f50f39 ("sctp: export some apis or variables for sctp_diag and reuse some for proc") Reported-by: syzbot+fe62a0c9aa6a85c6de16@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: Suppress the "Comparison to NULL could be written" warnings

2016-09-30T05:50:45Z

This is to suppress the checkpatch.pl warning "Comparison to NULL could be written". No functional changes here. Signed-off-by: Jia He Signed-off-by: David S. Miller

proc: Reduce cache miss in sctp_snmp_seq_show

2016-09-30T05:50:44Z

This is to use the generic interfaces snmp_get_cpu_field{,64}_batch to aggregate the data by going through all the items of each cpu sequentially. Signed-off-by: Jia He Signed-off-by: David S. Miller

net/sctp: always initialise sctp_ht_iter::start_fail

2016-08-13T22:10:16Z

sctp_transport_seq_start() does not currently clear iter->start_fail on success, but relies on it being zero when it is allocated (by seq_open_net()). This can be a problem in the following sequence: open() // allocates iter (and implicitly sets iter->start_fail = 0) read() - iter->start() // fails and sets iter->start_fail = 1 - iter->stop() // doesn't call sctp_transport_walk_stop() (correct) read() again - iter->start() // succeeds, but doesn't change iter->start_fail - iter->stop() // doesn't call sctp_transport_walk_stop() (wrong) We should initialize sctp_ht_iter::start_fail to zero if ->start() succeeds, otherwise it's possible that we leave an old value of 1 there, which will cause ->stop() to not call sctp_transport_walk_stop(), which causes all sorts of problems like not calling rcu_read_unlock() (and preempt_enable()), eventually leading to more warnings like this: BUG: sleeping function called from invalid context at mm/slab.h:388 in_atomic(): 0, irqs_disabled(): 0, pid: 16551, name: trinity-c2 Preemption disabled at:[] rhashtable_walk_start+0x46/0x150 [] preempt_count_add+0x1fb/0x280 [] _raw_spin_lock+0x12/0x40 [] rhashtable_walk_start+0x46/0x150 [] sctp_transport_walk_start+0x2f/0x60 [] sctp_transport_seq_start+0x4d/0x150 [] traverse+0x170/0x850 [] seq_read+0x7cc/0x1180 [] proc_reg_read+0xbc/0x180 [] do_loop_readv_writev+0x134/0x210 [] do_readv_writev+0x565/0x660 [] vfs_readv+0x67/0xa0 [] do_preadv+0x126/0x170 [] SyS_preadv+0xc/0x10 [] do_syscall_64+0x19c/0x410 [] return_from_SYSCALL_64+0x0/0x6a [] 0xffffffffffffffff Notice that this is a subtly different stacktrace from the one in commit 5fc382d875 ("net/sctp: terminate rhashtable walk correctly"). Cc: Xin Long Cc: Herbert Xu Cc: Eric W. Biederman Cc: Marcelo Ricardo Leitner Signed-off-by: Vegard Nossum Acked-By: Neil Horman Acked-by: Marcelo Ricardo Leitner Signed-off-by: David S. Miller

sctp: fix some rhashtable functions using in sctp proc/diag

2016-04-15T21:29:37Z

When rhashtable_walk_init return err, no release function should be called, and when rhashtable_walk_start return err, we should only invoke rhashtable_walk_exit to release the source. But now when sctp_transport_walk_start return err, we just call rhashtable_walk_stop/exit, and never care about if rhashtable_walk_init or start return err, which is so bad. We will fix it by calling rhashtable_walk_exit if rhashtable_walk_start return err in sctp_transport_walk_start, and if sctp_transport_walk_start return err, we do not need to call sctp_transport_walk_stop any more. For sctp proc, we will use 'iter->start_fail' to decide if we will call rhashtable_walk_stop/exit. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: merge the seq_start/next/exits in remaddrs and assocs

2016-04-15T21:29:36Z

In sctp proc, these three functions in remaddrs and assocs are the same. we should merge them into one. Signed-off-by: Xin Long Signed-off-by: David S. Miller

sctp: export some apis or variables for sctp_diag and reuse some for proc

2016-04-15T21:29:36Z

For some main variables in sctp.ko, we couldn't export it to other modules, so we have to define some api to access them. It will include sctp transport and endpoint's traversal. There are some transport traversal functions for sctp_diag, we can also use it for sctp_proc. cause they have the similar situation to traversal transport. v2->v3: - rhashtable_walk_init need the parameter gfp, because of recent upstrem update Signed-off-by: Xin Long Signed-off-by: David S. Miller

rhashtable: accept GFP flags in rhashtable_walk_init

2016-04-05T08:56:32Z

In certain cases, the 802.11 mesh pathtable code wants to iterate over all of the entries in the forwarding table from the receive path, which is inside an RCU read-side critical section. Enable walks inside atomic sections by allowing GFP_ATOMIC allocations for the walker state. Change all existing callsites to pass in GFP_KERNEL. Acked-by: Thomas Graf Signed-off-by: Bob Copeland [also adjust gfs2/glock.c and rhashtable tests] Signed-off-by: Johannes Berg

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

2016-03-08T17:34:12Z

Several cases of overlapping changes, as well as one instance (vxlan) of a bug fix in 'net' overlapping with code movement in 'net-next'. Signed-off-by: David S. Miller

sctp: sctp_remaddr_seq_show use the wrong variable to dump transport info

2016-03-01T22:35:44Z

Now in sctp_remaddr_seq_show(), we use variable *tsp to get the param *v. but *tsp is also used to traversal transport_addr_list, which will cover the previous value, and make sctp_transport_put work on the wrong transport. So fix it by adding a new variable to get the param *v. Fixes: fba4c330c5b9 ("sctp: hold transport before we access t->asoc in sctp proc") Signed-off-by: Xin Long Signed-off-by: David S. Miller