If you lose this race, it can iput a socket inode twice and you get a BUG
in fs/inode.c
When I added the option for user-space to close a socket, I added some
cruft to svc_delete_socket so that I could call that function when closing
a socket per user-space request.
This was the wrong thing to do. I should have just set SK_CLOSE and let
normal mechanisms do the work.
Not only wrong, but buggy. The locking is all wrong and it openned up a
race where-by a socket could be closed twice.
So this patch:
Introduces svc_close_socket which sets SK_CLOSE then either leave
the close up to a thread, or calls svc_delete_socket if it can
get SK_BUSY.
Adds a bias to sk_busy which is removed when SK_DEAD is set,
This avoid races around shutting down the socket.
Changes several 'spin_lock' to 'spin_lock_bh' where the _bh
was missing.
Bugzilla-url: http://bugzilla.kernel.org/show_bug.cgi?id=7916
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes a null pointer dereference when unloading the ipx module.
On initialization of the ipx module, registering certain packet
types can fail. When this happens, unloading the module later
dereferences NULL pointers. This patch fixes that. Please apply.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>
GCC (correctly) says:
net/socket.c: In function ‘sys_sendto’:
net/socket.c:1510: warning: ‘err’ may be used uninitialized in this function
net/socket.c: In function ‘sys_recvfrom’:
net/socket.c:1571: warning: ‘err’ may be used uninitialized in this function
sock_from_file() either returns filp->private_data or it
sets *err and returns NULL.
Callers return "err" on NULL, but filp->private_data could
be NULL.
Some minor rearrangements of error handling in sys_sendto
and sys_recvfrom solves the issue.
Signed-off-by: David S. Miller <davem@davemloft.net>
I believe dead code from sock_from_file() can be cleaned up.
All sockets are now built using sock_attach_fd(), that puts the 'sock' pointer
into file->private_data and &socket_file_ops into file->f_op
I could not find a place where file->private_data could be set to NULL,
keeping opened the file.
So to get 'sock' from a 'file' pointer, either :
- This is a socket file (f_op == &socket_file_ops), and we can directly get
'sock' from private_data.
- This is not a socket, we return -ENOTSOCK and dont even try to find a socket
via dentry/inode :)
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
ehash table layout is currently this one :
First half of this table is used by sockets not in TIME_WAIT state
Second half of it is used by sockets in TIME_WAIT state.
This is non optimal because of for a given hash or socket, the two chain heads
are located in separate cache lines.
Moreover the locks of the second half are never used.
If instead of this halving, we use two list heads in inet_ehash_bucket instead
of only one, we probably can avoid one cache miss, and reduce ram usage,
particularly if sizeof(rwlock_t) is big (various CONFIG_DEBUG_SPINLOCK,
CONFIG_DEBUG_LOCK_ALLOC settings). So we still halves the table but we keep
together related chains to speedup lookups and socket state change.
In this patch I did not try to align struct inet_ehash_bucket, but a future
patch could try to make this structure have a convenient size (a power of two
or a multiple of L1_CACHE_SIZE).
I guess rwlock will just vanish as soon as RCU is plugged into ehash :) , so
maybe we dont need to scratch our heads to align the bucket...
Note : In case struct inet_ehash_bucket is not a power of two, we could
probably change alloc_large_system_hash() (in case it use __get_free_pages())
to free the unused space. It currently allocates a big zone, but the last
quarter of it could be freed. Again, this should be a temporary 'problem'.
Patch tested on ipv4 tcp only, but should be OK for IPV6 and DCCP.
Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Jennifer Hunt <jenhunt@us.ibm.com>
This patch adds AF_IUCV socket support.
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add rewritten IUCV base code to net/iucv.
Signed-off-by: Frank Pavlic <fpavlic@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
View the active forwarded calls
cat /proc/net/x25/forward
Signed-off-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
echo "1" > /proc/sys/net/x25/x25_forward
To turn on x25_forwarding, defaults to off
Requires the previous patch.
Signed-off-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds call forwarding to X.25, allowing it to operate like an X.25 router.
Useful if one needs to manipulate X.25 traffic with tools like tc.
This is an update/cleanup based off a patch submitted by Daniel Ferenci a few years ago.
Thanks Alan for the feedback.
Added the null check to the clones.
Moved the skb_clone's into the forwarding functions.
Worked ok with Cisco XoT, linux X.25 back to back, and some old NTUs/PADs.
Signed-off-by: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add CONFIG_NET_KEY_MIGRATE option which makes it possible for user
application to send or receive MIGRATE message to/from PF_KEY socket.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend PF_KEYv2 framework so that user application can take advantage
of MIGRATE feature via PF_KEYv2 interface. User application can either
send or receive an MIGRATE message to/from PF_KEY socket.
Detail information can be found in the internet-draft
<draft-sugimoto-mip6-pfkey-migrate>.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add CONFIG_XFRM_MIGRATE option which makes it possible for for user
application to send or receive MIGRATE message to/from netlink socket.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add user interface for handling XFRM_MSG_MIGRATE. The message is issued
by user application. When kernel receives the message, procedure of
updating XFRM databases will take place.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Extend the XFRM framework so that endpoint address(es) in the XFRM
databases could be dynamically updated according to a request (MIGRATE
message) from user application. Target XFRM policy is first identified
by the selector in the MIGRATE message. Next, the endpoint addresses
of the matching templates and XFRM states are updated according to
the MIGRATE message.
Signed-off-by: Shinta Sugimoto <shinta.sugimoto@ericsson.com>
Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>