linux.git/net/dccp, branch v5.0-rc2

mm: convert totalram_pages and totalhigh_pages variables to atomic

2018-12-28T20:11:47+00:00

totalram_pages and totalhigh_pages are made static inline function.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 So it seemes
better to remove the lock and convert variables to atomic, with preventing
poteintial store-to-read tearing as a bonus.

[akpm@linux-foundation.org: coding style fixes]
Link: http://lkml.kernel.org/r/1542090790-21750-4-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS 
Suggested-by: Michal Hocko 
Suggested-by: Vlastimil Babka 
Reviewed-by: Konstantin Khlebnikov 
Reviewed-by: Pavel Tatashin 
Acked-by: Michal Hocko 
Acked-by: Vlastimil Babka 
Cc: David Hildenbrand 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: reference totalram_pages and managed_pages once per function

2018-12-28T20:11:47+00:00

Patch series "mm: convert totalram_pages, totalhigh_pages and managed
pages to atomic", v5.

This series converts totalram_pages, totalhigh_pages and
zone->managed_pages to atomic variables.

totalram_pages, zone->managed_pages and totalhigh_pages updates are
protected by managed_page_count_lock, but readers never care about it.
Convert these variables to atomic to avoid readers potentially seeing a
store tear.

Main motivation was that managed_page_count_lock handling was complicating
things.  It was discussed in length here,
https://lore.kernel.org/patchwork/patch/995739/#1181785 It seemes better
to remove the lock and convert variables to atomic.  With the change,
preventing poteintial store-to-read tearing comes as a bonus.

This patch (of 4):

This is in preparation to a later patch which converts totalram_pages and
zone->managed_pages to atomic variables.  Please note that re-reading the
value might lead to a different value and as such it could lead to
unexpected behavior.  There are no known bugs as a result of the current
code but it is better to prevent from them in principle.

Link: http://lkml.kernel.org/r/1542090790-21750-2-git-send-email-arunks@codeaurora.org
Signed-off-by: Arun KS 
Reviewed-by: Konstantin Khlebnikov 
Reviewed-by: David Hildenbrand 
Acked-by: Michal Hocko 
Acked-by: Vlastimil Babka 
Reviewed-by: Pavel Tatashin 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

net: dccp: fix kernel crash on module load

2018-12-24T23:27:56+00:00

Patch eedbbb0d98b2 "net: dccp: initialize (addr,port) ..."
added calling to inet_hashinfo2_init() from dccp_init().

However, inet_hashinfo2_init() is marked as __init(), and
thus the kernel panics when dccp is loaded as module. Removing
__init() tag from inet_hashinfo2_init() is not feasible because
it calls into __init functions in mm.

This patch adds inet_hashinfo2_init_mod() function that can
be called after the init phase is done; changes dccp_init() to
call the new function; un-marks inet_hashinfo2_init() as
exported.

Fixes: eedbbb0d98b2 ("net: dccp: initialize (addr,port) ...")
Reported-by: kernel test robot 
Signed-off-by: Peter Oskolkov 
Signed-off-by: David S. Miller

net: dccp: initialize (addr,port) listening hashtable

2018-12-18T07:11:48+00:00

Commit d9fbc7f6431f "net: tcp: prefer listeners bound to an address"
removes port-only listener lookups. This caused segfaults in DCCP
lookups because DCCP did not initialize the (addr,port) hashtable.

This patch adds said initialization.

The only non-trivial issue here is the size of the new hashtable.
It seemed reasonable to make it match the size of the port-only
hashtable (= INET_LHTABLE_SIZE) that was used previously. Other
parameters to inet_hashinfo2_init() match those used in TCP.

V2 changes: marked inet_hashinfo2_init as an exported symbol
so that DCCP compiles when configured as a module.

Tested: syzcaller issues fixed; the second patch in the patchset
        tests that DCCP lookups work correctly.

Fixes: d9fbc7f6431f "net: tcp: prefer listeners bound to an address"
Reported-by: syzcaller 
Signed-off-by: Peter Oskolkov 
Signed-off-by: David S. Miller

Revert "net: dccp: initialize (addr,port) listening hashtable"

2018-12-16T20:36:41+00:00

This reverts commit ec49d83f245453515a9b6e88324e27bbcb69fbae.

Cause build failures when DCCP is modular.

ERROR: "inet_hashinfo2_init" [net/dccp/dccp.ko] undefined!

Signed-off-by: David S. Miller

net: dccp: initialize (addr,port) listening hashtable

2018-12-16T20:14:29+00:00

Commit d9fbc7f6431f "net: tcp: prefer listeners bound to an address"
removes port-only listener lookups. This caused segfaults in DCCP
lookups because DCCP did not initialize the (addr,port) hashtable.

This patch adds said initialization.

The only non-trivial issue here is the size of the new hashtable.
It seemed reasonable to make it match the size of the port-only
hashtable (= INET_LHTABLE_SIZE) that was used previously. Other
parameters to inet_hashinfo2_init() match those used in TCP.

Tested: syzcaller issues fixed; the second patch in the patchset
        tests that DCCP lookups work correctly.

Fixes: d9fbc7f6431f "net: tcp: prefer listeners bound to an address"
Reported-by: syzcaller 
Signed-off-by: Peter Oskolkov 
Signed-off-by: David S. Miller

net: Convert protocol error handlers from void to int

2018-11-09T01:13:08+00:00

We'll need this to handle ICMP errors for tunnels without a sending socket
(i.e. FoU and GUE). There, we might have to look up different types of IP
tunnels, registered as network protocols, before we get a match, so we
want this for the error handlers of IPPROTO_IPIP and IPPROTO_IPV6 in both
inet_protos and inet6_protos. These error codes will be used in the next
patch.

For consistency, return sensible error codes in protocol error handlers
whenever handlers can't handle errors because, even if valid, they don't
match a protocol or any of its states.

This has no effect on existing error handling paths.

Signed-off-by: Stefano Brivio 
Reviewed-by: Sabrina Dubroca 
Signed-off-by: David S. Miller

inet: minor optimization for backlog setting in listen(2)

2018-11-08T06:31:07+00:00

Set the backlog earlier in inet_dccp_listen() and inet_listen(),
then we can avoid the redundant setting.

Signed-off-by: Yafang Shao 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller

Revert "net: simplify sock_poll_wait"

2018-10-23T17:57:06+00:00

This reverts commit dd979b4df817e9976f18fb6f9d134d6bc4a3c317.

This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an
internal TCP socket for the initial handshake with the remote peer.
Whenever the SMC connection can not be established this TCP socket is
used as a fallback. All socket operations on the SMC socket are then
forwarded to the TCP socket. In case of poll, the file->private_data
pointer references the SMC socket because the TCP socket has no file
assigned. This causes tcp_poll to wait on the wrong socket.

Signed-off-by: Karsten Graul 
Signed-off-by: David S. Miller

inet: make sure to grab rcu_read_lock before using ireq->ireq_opt

2018-10-02T22:52:12+00:00

Timer handlers do not imply rcu_read_lock(), so my recent fix
triggered a LOCKDEP warning when SYNACK is retransmit.

Lets add rcu_read_lock()/rcu_read_unlock() pairs around ireq->ireq_opt
usages instead of guessing what is done by callers, since it is
not worth the pain.

Get rid of ireq_opt_deref() helper since it hides the logic
without real benefit, since it is now a standard rcu_dereference().

Fixes: 1ad98e9d1bdf ("tcp/dccp: fix lockdep issue when SYN is backlogged")
Signed-off-by: Eric Dumazet 
Reported-by: Willem de Bruijn 
Signed-off-by: David S. Miller