This patch makes socketpair() use error paths which do not
rely on heavy-weight call to sys_close(): it's better to try
to push the file descriptor to userspace before installing
the socket file to the file descriptor, so that errors are
catched earlier and being easier to handle.
Using sys_close() seems to be the exception, while writing the
file descriptor before installing it look like it's more or less
the norm: eg. except for code used in init/, error handling
involve fput() and put_unused_fd(), but not sys_close().
This make socketpair() usage of sys_close() quite unusual.
So it deserves to be replaced by the common pattern relying on
fput() and put_unused_fd() just like, for example, the one used
in pipe(2) or recvmsg(2).
Three distinct error paths are still needed since calling
fput() on file structure returned by sock_alloc_file() will
implicitly call sock_release() on the associated socket
structure.
Cc: David S. Miller <davem@davemloft.net>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Link: http://marc.info/?i=1385979146-13825-1-git-send-email-ydroneaud@opteya.com
Signed-off-by: David S. Miller <davem@davemloft.net>
Ben Hutchings says:
====================
SIOCGHWTSTAMP ioctl
1. Add the SIOCGHWTSTAMP ioctl and update the timestamping
documentation.
2. Implement SIOCGHWTSTAMP in most drivers that support SIOCSHWTSTAMP.
3. Add a test program to exercise SIOC{G,S}HWTSTAMP.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
If kmsg->msg_namelen > sizeof(struct sockaddr_storage) then in the
original code that would lead to memory corruption in the kernel if you
had audit configured. If you didn't have audit configured it was
harmless.
There are some programs such as beta versions of Ruby which use too
large of a buffer and returning an error code breaks them. We should
clamp the ->msg_namelen value instead.
Fixes: 1661bf364a ("net: heap overflow in __audit_sockaddr()")
Reported-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Tested-by: Eric Wong <normalperson@yhbt.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In that case it is probable that kernel code overwrote part of the
stack. So we should bail out loudly here.
The BUG_ON may be removed in future if we are sure all protocols are
conformant.
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.
This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.
Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.
Also document these changes in include/linux/net.h as suggested by David
Miller.
Changes since RFC:
Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.
With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
msg->msg_name = NULL
".
This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.
Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.
Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
SIOCSHWTSTAMP returns the real configuration to the application
using it, but there is currently no way for any other
application to find out the configuration non-destructively.
Add a new ioctl for this, making it unprivileged.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
We don't need to check that ifr_data itself is a valid user pointer,
but we should check &ifr_data is. Thankfully the copy of ifr_name is
checked, so this can only leak a few bytes from immediately above the
user address limit.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
We need to cap ->msg_namelen or it leads to a buffer overflow when we
to the memcpy() in __audit_sockaddr(). It requires CAP_AUDIT_CONTROL to
exploit this bug.
The call tree is:
___sys_recvmsg()
move_addr_to_user()
audit_sockaddr()
__audit_sockaddr()
Reported-by: Jüri Aedla <juri.aedla@gmail.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull aio changes from Ben LaHaise:
"First off, sorry for this pull request being late in the merge window.
Al had raised a couple of concerns about 2 items in the series below.
I addressed the first issue (the race introduced by Gu's use of
mm_populate()), but he has not provided any further details on how he
wants to rework the anon_inode.c changes (which were sent out months
ago but have yet to be commented on).
The bulk of the changes have been sitting in the -next tree for a few
months, with all the issues raised being addressed"
* git://git.kvack.org/~bcrl/aio-next: (22 commits)
aio: rcu_read_lock protection for new rcu_dereference calls
aio: fix race in ring buffer page lookup introduced by page migration support
aio: fix rcu sparse warnings introduced by ioctx table lookup patch
aio: remove unnecessary debugging from aio_free_ring()
aio: table lookup: verify ctx pointer
staging/lustre: kiocb->ki_left is removed
aio: fix error handling and rcu usage in "convert the ioctx list to table lookup v3"
aio: be defensive to ensure request batching is non-zero instead of BUG_ON()
aio: convert the ioctx list to table lookup v3
aio: double aio_max_nr in calculations
aio: Kill ki_dtor
aio: Kill ki_users
aio: Kill unneeded kiocb members
aio: Kill aio_rw_vect_retry()
aio: Don't use ctx->tail unnecessarily
aio: io_cancel() no longer returns the io_event
aio: percpu ioctx refcount
aio: percpu reqs_available
aio: reqs_active -> reqs_available
aio: fix build when migration is disabled
...
I found the following pattern that leads in to interesting findings:
grep -r "ret.*|=.*__put_user" *
grep -r "ret.*|=.*__get_user" *
grep -r "ret.*|=.*__copy" *
The __put_user() calls in compat_ioctl.c, ptrace compat, signal compat,
since those appear in compat code, we could probably expect the kernel
addresses not to be reachable in the lower 32-bit range, so I think they
might not be exploitable.
For the "__get_user" cases, I don't think those are exploitable: the worse
that can happen is that the kernel will copy kernel memory into in-kernel
buffers, and will fail immediately afterward.
The alpha csum_partial_copy_from_user() seems to be missing the
access_ok() check entirely. The fix is inspired from x86. This could
lead to information leak on alpha. I also noticed that many architectures
map csum_partial_copy_from_user() to csum_partial_copy_generic(), but I
wonder if the latter is performing the access checks on every
architectures.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rename LL_SO to BUSY_POLL_SO
Rename sysctl_net_ll_{read,poll} to sysctl_busy_{read,poll}
Fix up users of these variables.
Fix documentation for sysctl.
a patch for the socket.7 man page will follow separately,
because of limitations of my mail setup.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Rename functions in include/net/ll_poll.h to busy wait.
Clarify documentation about expected power use increase.
Rename POLL_LL to POLL_BUSY_LOOP.
Add need_resched() testing to poll/select busy loops.
Note, that in select and poll can_busy_poll is dynamic and is
updated continuously to reflect the existence of supported
sockets with valid queue information.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
select/poll busy-poll support.
Split sysctl value into two separate ones, one for read and one for poll.
updated Documentation/sysctl/net.txt
Add a new poll flag POLL_LL. When this flag is set, sock_poll will call
sk_poll_ll if possible. sock_poll sets this flag in its return value
to indicate to select/poll when a socket that can busy poll is found.
When poll/select have nothing to report, call the low-level
sock_poll again until we are out of time or we find something.
Once the system call finds something, it stops setting POLL_LL, so it can
return the result to the user ASAP.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
adds a socket option for low latency polling.
This allows overriding the global sysctl value with a per-socket one.
Unexport sysctl_net_ll_poll since for now it's not needed in modules.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is no reason for sysctl_net_ll_poll to be an unsigned long.
Change it into an unsigned int.
Fix the proc handler.
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Adds an ndo_ll_poll method and the code that supports it.
This method can be used by low latency applications to busy-poll
Ethernet device queues directly from the socket code.
sysctl_net_ll_poll controls how many microseconds to poll.
Default is zero (disabled).
Individual protocol support will be added by subsequent patches.
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Tested-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
I broke them in this commit:
commit 1be374a051
Author: Andy Lutomirski <luto@amacapital.net>
Date: Wed May 22 14:07:44 2013 -0700
net: Block MSG_CMSG_COMPAT in send(m)msg and recv(m)msg
This patch adds __sys_sendmsg and __sys_sendmsg as common helpers that accept
MSG_CMSG_COMPAT and blocks MSG_CMSG_COMPAT at the syscall entrypoints. It
also reverts some unnecessary checks in sys_socketcall.
Apparently I was suffering from underscore blindness the first time around.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Tested-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Conflicts:
net/netfilter/nf_log.c
The conflict in nf_log.c is that in 'net' we added CONFIG_PROC_FS
protection around foo_proc_entry() calls to fix a build failure,
whereas in Pablo's tree a guard if() test around a call is
remove_proc_entry() was removed. Trivially resolved.
Pablo Neira Ayuso says:
====================
The following patchset contains the first batch of
Netfilter/IPVS updates for your net-next tree, they are:
* Three patches with improvements and code refactorization
for nfnetlink_queue, from Florian Westphal.
* FTP helper now parses replies without brackets, as RFC1123
recommends, from Jeff Mahoney.
* Rise a warning to tell everyone about ULOG deprecation,
NFLOG has been already in the kernel tree for long time
and supersedes the old logging over netlink stub, from
myself.
* Don't panic if we fail to load netfilter core framework,
just bail out instead, from myself.
* Add cond_resched_rcu, used by IPVS to allow rescheduling
while walking over big hashtables, from Simon Horman.
* Change type of IPVS sysctl_sync_qlen_max sysctl to avoid
possible overflow, from Zhang Yanfei.
* Use strlcpy instead of strncpy to skip zeroing of already
initialized area to write the extension names in ebtables,
from Chen Gang.
* Use already existing per-cpu notrack object from xt_CT,
from Eric Dumazet.
* Save explicit socket lookup in xt_socket now that we have
early demux, also from Eric Dumazet.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
To: linux-kernel@vger.kernel.org
Cc: x86@kernel.org, trinity@vger.kernel.org, Andy Lutomirski <luto@amacapital.net>, netdev@vger.kernel.org, "David S.
Miller" <davem@davemloft.net>
Subject: [PATCH 5/5] net: Block MSG_CMSG_COMPAT in send(m)msg and recv(m)msg
MSG_CMSG_COMPAT is (AFAIK) not intended to be part of the API --
it's a hack that steals a bit to indicate to other networking code
that a compat entry was used. So don't allow it from a non-compat
syscall.
This prevents an oops when running this code:
int main()
{
int s;
struct sockaddr_in addr;
struct msghdr *hdr;
char *highpage = mmap((void*)(TASK_SIZE_MAX - 4096), 4096,
PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS | MAP_FIXED, -1, 0);
if (highpage == MAP_FAILED)
err(1, "mmap");
s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
if (s == -1)
err(1, "socket");
addr.sin_family = AF_INET;
addr.sin_port = htons(1);
addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
if (connect(s, (struct sockaddr*)&addr, sizeof(addr)) != 0)
err(1, "connect");
void *evil = highpage + 4096 - COMPAT_MSGHDR_SIZE;
printf("Evil address is %p\n", evil);
if (syscall(__NR_sendmmsg, s, evil, 1, MSG_CMSG_COMPAT) < 0)
err(1, "sendmmsg");
return 0;
}
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
