linux-stable.git/net/socket.c, branch linux-2.6.16.y

[NET]: Zero length write() on socket should not simply return 0.

2007-10-18T16:47:05+00:00

This fixes kernel bugzilla #5731

It should generate an empty packet for datagram protocols when the
socket is connected, for one.

The check is doubly-wrong because all that a write() can be is a
sendmsg() call with a NULL msg_control and a single entry iovec.  No
special semantics should be assigned to it, therefore the zero length
check should be removed entirely.

This matches the behavior of BSD and several other systems.

Alan Cox notes that SuSv3 says the behavior of a zero length write on
non-files is "unspecified", but that's kind of useless since BSD has
defined this behavior for a quarter century and BSD is essentially
what application folks code to.

Based upon a patch from Stephen Hemminger.

Adrian Bunk:
Backported to 2.6.16.

Signed-off-by: David S. Miller 
Signed-off-by: Adrian Bunk

[PATCH] percpu data: only iterate over possible CPUs

2006-02-05T19:06:51+00:00

percpu_data blindly allocates bootmem memory to store NR_CPUS instances of
cpudata, instead of allocating memory only for possible cpus.

As a preparation for changing that, we need to convert various 0 -> NR_CPUS
loops to use for_each_cpu().

(The above only applies to users of asm-generic/percpu.h.  powerpc has gone it
alone and is presently only allocating memory for present CPUs, so it's
currently corrupting memory).

Signed-off-by: Eric Dumazet 
Cc: "David S. Miller" 
Cc: James Bottomley 
Acked-by: Ingo Molnar 
Cc: Jens Axboe 
Cc: Anton Blanchard 
Acked-by: William Irwin 
Cc: Andi Kleen 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[NET]: Remove more unneeded typecasts on *malloc()

2006-01-12T00:32:14+00:00

This removes more unneeded casts on the return value for kmalloc(),
sock_kmalloc(), and vmalloc().

Signed-off-by: Kris Katterjohn 
Acked-by: James Morris 
Signed-off-by: David S. Miller

[NET]: Add a dev_ioctl() fallback to sock_ioctl()

2006-01-03T22:18:33+00:00

Currently all network protocols need to call dev_ioctl as the default
fallback in their ioctl implementations.  This patch adds a fallback
to dev_ioctl to sock_ioctl if the protocol returned -ENOIOCTLCMD.
This way all the procotol ioctl handlers can be simplified and we don't
need to export dev_ioctl.

Signed-off-by: Christoph Hellwig 
Signed-off-by: David S. Miller

[NET]: restructure sock_aio_{read,write} / sock_{readv,writev}

2006-01-03T21:11:18+00:00

Mid-term I plan to restructure the file_operations so that we don't need
to have all these duplicate aio and vectored versions.  This patch is
a small step in that direction but also a worthwile cleanup on it's own:

(1) introduce a alloc_sock_iocb helper that encapsulates allocating a
    proper sock_iocb
(2) add do_sock_read and do_sock_write helpers for common read/write
    code

Signed-off-by: Christoph Hellwig 
Signed-off-by: David S. Miller

[NET]: Fix sock_init() return value.

2006-01-03T21:11:17+00:00

It needs to return zero now that it is an initcall.

Also, net/nonet.c no longer needs a dummy sock_init().

Signed-off-by: David S. Miller

[NET]: Small cleanup to socket initialization

2006-01-03T21:11:14+00:00

sock_init can be done as a core_initcall instead of calling
it directly in init/main.c

Also I removed an out of date #ifdef.

Signed-off-by: Andi Kleen 
Signed-off-by: David S. Miller

[NET]: Fix module reference counts for loadable protocol modules

2005-09-27T22:23:38+00:00

I have been experimenting with loadable protocol modules, and ran into
several issues with module reference counting.

The first issue was that __module_get failed at the BUG_ON check at
the top of the routine (checking that my module reference count was
not zero) when I created the first socket. When sk_alloc() is called,
my module reference count was still 0. When I looked at why sctp
didn't have this problem, I discovered that sctp creates a control
socket during module init (when the module ref count is not 0), which
keeps the reference count non-zero. This section has been updated to
address the point Stephen raised about checking the return value of
try_module_get().

The next problem arose when my socket init routine returned an error.
This resulted in my module reference count being decremented below 0.
My socket ops->release routine was also being called. The issue here
is that sock_release() calls the ops->release routine and decrements
the ref count if sock->ops is not NULL. Since the socket probably
didn't get correctly initialized, this should not be done, so we will
set sock->ops to NULL because we will not call try_module_get().

While searching for another bug, I also noticed that sys_accept() has
a possibility of doing a module_put() when it did not do an
__module_get so I re-ordered the call to security_socket_accept().

Signed-off-by: Frank Filz 
Signed-off-by: David S. Miller

[NET]: Make sure ctl buffer is aligned properly in sys_sendmsg().

2005-09-26T21:28:02+00:00

It's on the stack and declared as "unsigned char[]", but pointers
and similar can be in here thus we need to give it an explicit
alignment attribute.

Signed-off-by: Alex Williamson 
Signed-off-by: Andrew Morton 
Signed-off-by: David S. Miller

[NET]: Do not leak MSG_CMSG_COMPAT into userspace.

2005-09-16T23:51:01+00:00

Noticed by Sridhar Samudrala.

Signed-off-by: David S. Miller