linux-toradex.git/drivers/tty/n_gsm.c, branch v4.4.85

TTY: n_gsm, fix false positive WARN_ON

2016-06-01T19:15:52+00:00

commit d175feca89a1c162f60f4e3560ca7bc9437c65eb upstream.

Dmitry reported, that the current cleanup code in n_gsm can trigger a
warning:
WARNING: CPU: 2 PID: 24238 at drivers/tty/n_gsm.c:2048 gsm_cleanup_mux+0x166/0x6b0()
...
Call Trace:
...
 [] warn_slowpath_null+0x29/0x30 kernel/panic.c:490
 [] gsm_cleanup_mux+0x166/0x6b0 drivers/tty/n_gsm.c:2048
 [] gsmld_open+0x5b7/0x7a0 drivers/tty/n_gsm.c:2386
 [] tty_ldisc_open.isra.2+0x78/0xd0 drivers/tty/tty_ldisc.c:447
 [] tty_set_ldisc+0x1ca/0xa70 drivers/tty/tty_ldisc.c:567
 [<     inline     >] tiocsetd drivers/tty/tty_io.c:2650
 [] tty_ioctl+0xb2a/0x2140 drivers/tty/tty_io.c:2883
...

But this is a legal path when open fails to find a space in the
gsm_mux array and tries to clean up. So make it a standard test
instead of a warning.

Reported-by: "Dmitry Vyukov" 
Cc: Alan Cox 
Link: http://lkml.kernel.org/r/CACT4Y+bHQbAB68VFi7Romcs-Z9ZW3kQRvcq+BvHH1oa5NcAdLA@mail.gmail.com
Fixes: 5a640967 ("tty/n_gsm.c: fix a memory leak in gsmld_open()")
Signed-off-by: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman

tty: Convert use of __constant_htons to htons

2015-07-23T22:10:25+00:00

In little endian cases, macro htons unfolds to __swab16 which
provides special case for constants. In big endian cases,
__constant_htons and htons expand directly to the same expression.
So, replace __constant_htons with htons with the goal of getting
rid of the definition of __constant_htons completely.

The semantic patch that performs this transformation is as follows:

@@expression x;@@

- __constant_htons(x)
+ htons(x)

Signed-off-by: Vaishali Thakkar 
Signed-off-by: Greg Kroah-Hartman

tty: Spelling s/reseved/reserved/

2015-05-24T20:06:08+00:00

Signed-off-by: Geert Uytterhoeven 
Signed-off-by: Greg Kroah-Hartman

Merge 4.1-rc4 into tty-next

2015-05-18T21:08:58+00:00

This resolves some tty driver merge issues.

Signed-off-by: Greg Kroah-Hartman

tty/n_gsm.c: fix a memory leak when gsmtty is removed

2015-05-10T17:25:32+00:00

when gsmtty_remove put dlci, it will cause memory leak if dlci->port's refcount is zero.
So we do the cleanup work in .cleanup callback instead.

dlci will be last put in two call chains.
1) gsmld_close -> gsm_cleanup_mux -> gsm_dlci_release -> dlci_put
2) gsmld_remove -> dlci_put
so there is a race. the memory leak depends on the race.

In call chain 2. we hit the memory leak. below comment tells.

release_tty -> tty_driver_remove_tty -> gsmtty_remove -> dlci_put -> tty_port_destructor (WARN_ON(port->itty) and return directly)
                         |
                tty->port->itty = NULL;
                         |
                tty_kref_put ---> release_one_tty -> gsmtty_cleanup (added by our patch)

So our patch fix the memory leak by doing the cleanup work after tty core did.

Signed-off-by: Pan Xinhui 
Fixes: dfabf7ffa30585
Cc: stable  # 3.14+
Acked-by: Jiri Slaby 
Signed-off-by: Greg Kroah-Hartman

tty: remove buf parameter from tty_name()

2015-05-06T20:26:57+00:00

tty_name no longer uses the buf parameter, so remove it along with all
the 64 byte stack buffers that used to be passed in.

Mostly generated by the coccinelle script

@depends on patch@
identifier buf;
constant C;
expression tty;
@@
- char buf[C];
  <+...
- tty_name(tty, buf)
+ tty_name(tty)
  ...+>

allmodconfig compiles, so I'm fairly confident the stack buffers
weren't used for other purposes as well.

Signed-off-by: Rasmus Villemoes 
Reviewed-by: Peter Hurley 
Acked-by: Jesper Nilsson 
Acked-by: Dmitry Torokhov 
Signed-off-by: Greg Kroah-Hartman

n_gsm: Drop unneeded cast on netdev_priv

2015-04-10T12:43:48+00:00

The result of netdev_priv is already implicitly cast to the type of the
left side of the assignment.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// 
@@
type T;
T *x;
@@

x =
- (T *)
  netdev_priv(...)
// 

Signed-off-by: Julia Lawall 
Signed-off-by: Greg Kroah-Hartman

tty/n_gsm: fix sparse warning

2015-03-26T15:10:10+00:00

this patch fixes following sparse warning:

n_gsm.c:2827:22: warning: symbol 'tty_ldisc_packet' was not declared. Should it be static?

Signed-off-by: Lad, Prabhakar 
Acked-by: Alan Cox 
Signed-off-by: Greg Kroah-Hartman

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

2014-08-06T16:38:14+00:00

Pull networking updates from David Miller:
 "Highlights:

   1) Steady transitioning of the BPF instructure to a generic spot so
      all kernel subsystems can make use of it, from Alexei Starovoitov.

   2) SFC driver supports busy polling, from Alexandre Rames.

   3) Take advantage of hash table in UDP multicast delivery, from David
      Held.

   4) Lighten locking, in particular by getting rid of the LRU lists, in
      inet frag handling.  From Florian Westphal.

   5) Add support for various RFC6458 control messages in SCTP, from
      Geir Ola Vaagland.

   6) Allow to filter bridge forwarding database dumps by device, from
      Jamal Hadi Salim.

   7) virtio-net also now supports busy polling, from Jason Wang.

   8) Some low level optimization tweaks in pktgen from Jesper Dangaard
      Brouer.

   9) Add support for ipv6 address generation modes, so that userland
      can have some input into the process.  From Jiri Pirko.

  10) Consolidate common TCP connection request code in ipv4 and ipv6,
      from Octavian Purdila.

  11) New ARP packet logger in netfilter, from Pablo Neira Ayuso.

  12) Generic resizable RCU hash table, with intial users in netlink and
      nftables.  From Thomas Graf.

  13) Maintain a name assignment type so that userspace can see where a
      network device name came from (enumerated by kernel, assigned
      explicitly by userspace, etc.) From Tom Gundersen.

  14) Automatic flow label generation on transmit in ipv6, from Tom
      Herbert.

  15) New packet timestamping facilities from Willem de Bruijn, meant to
      assist in measuring latencies going into/out-of the packet
      scheduler, latency from TCP data transmission to ACK, etc"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1536 commits)
  cxgb4 : Disable recursive mailbox commands when enabling vi
  net: reduce USB network driver config options.
  tg3: Modify tg3_tso_bug() to handle multiple TX rings
  amd-xgbe: Perform phy connect/disconnect at dev open/stop
  amd-xgbe: Use dma_set_mask_and_coherent to set DMA mask
  net: sun4i-emac: fix memory leak on bad packet
  sctp: fix possible seqlock seadlock in sctp_packet_transmit()
  Revert "net: phy: Set the driver when registering an MDIO bus device"
  cxgb4vf: Turn off SGE RX/TX Callback Timers and interrupts in PCI shutdown routine
  team: Simplify return path of team_newlink
  bridge: Update outdated comment on promiscuous mode
  net-timestamp: ACK timestamp for bytestreams
  net-timestamp: TCP timestamping
  net-timestamp: SCHED timestamp on entering packet scheduler
  net-timestamp: add key to disambiguate concurrent datagrams
  net-timestamp: move timestamp flags out of sk_flags
  net-timestamp: extend SCM_TIMESTAMPING ancillary data struct
  cxgb4i : Move stray CPL definitions to cxgb4 driver
  tcp: reduce spurious retransmits due to transient SACK reneging
  qlcnic: Initialize dcbnl_ops before register_netdev
  ...

tty/n_gsm.c: fix a memory leak in gsmld_open

2014-08-01T23:04:54+00:00

If gsmld_attach_gsm fails, the gsm is not used anymore.
tty core will not call gsmld_close to do the cleanup work.
tty core just restore to the tty old ldisc.
That always causes memory leak.

Signed-off-by: xinhui.pan 
Reported-by: Peter Hurley 
Signed-off-by: Greg Kroah-Hartman