kernel.git/net/smc, branch linux-4.11.y

net/smc: Add warning about remote memory exposure

2017-06-07T10:10:01Z

[ Upstream commit 19a0f7e37c0761a0a1cbf550705a6063c9675223 ] The driver explicitly bypasses APIs to register all memory once a connection is made, and thus allows remote access to memory. Signed-off-by: Christoph Hellwig Signed-off-by: Leon Romanovsky Acked-by: Ursula Braun Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

smc: switch to usage of IB_PD_UNSAFE_GLOBAL_RKEY

2017-06-07T10:10:01Z

[ Upstream commit 263eec9b2a82e8697d064709414914b5b10ac538 ] Currently, SMC enables remote access to physical memory when a user has successfully configured and established an SMC-connection until ten minutes after the last SMC connection is closed. Because this is considered a security risk, drivers are supposed to use IB_PD_UNSAFE_GLOBAL_RKEY in such a case. This patch changes the current SMC code to use IB_PD_UNSAFE_GLOBAL_RKEY. This improves user awareness, but does not remove the security risk itself. Signed-off-by: Ursula Braun Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: Work around lockdep limitation in sockets that use sockets

2017-03-10T02:23:27Z

Lockdep issues a circular dependency warning when AFS issues an operation through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem. The theory lockdep comes up with is as follows: (1) If the pagefault handler decides it needs to read pages from AFS, it calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but creating a call requires the socket lock: mmap_sem must be taken before sk_lock-AF_RXRPC (2) afs_open_socket() opens an AF_RXRPC socket and binds it. rxrpc_bind() binds the underlying UDP socket whilst holding its socket lock. inet_bind() takes its own socket lock: sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET (3) Reading from a TCP socket into a userspace buffer might cause a fault and thus cause the kernel to take the mmap_sem, but the TCP socket is locked whilst doing this: sk_lock-AF_INET must be taken before mmap_sem However, lockdep's theory is wrong in this instance because it deals only with lock classes and not individual locks. The AF_INET lock in (2) isn't really equivalent to the AF_INET lock in (3) as the former deals with a socket entirely internal to the kernel that never sees userspace. This is a limitation in the design of lockdep. Fix the general case by: (1) Double up all the locking keys used in sockets so that one set are used if the socket is created by userspace and the other set is used if the socket is created by the kernel. (2) Store the kern parameter passed to sk_alloc() in a variable in the sock struct (sk_kern_sock). This informs sock_lock_init(), sock_init_data() and sk_clone_lock() as to the lock keys to be used. Note that the child created by sk_clone_lock() inherits the parent's kern setting. (3) Add a 'kern' parameter to ->accept() that is analogous to the one passed in to ->create() that distinguishes whether kernel_accept() or sys_accept4() was the caller and can be passed to sk_alloc(). Note that a lot of accept functions merely dequeue an already allocated socket. I haven't touched these as the new socket already exists before we get the parameter. Note also that there are a couple of places where I've made the accepted socket unconditionally kernel-based: irda_accept() rds_rcp_accept_one() tcp_accept_from_sock() because they follow a sock_create_kern() and accept off of that. Whilst creating this, I noticed that lustre and ocfs don't create sockets through sock_create_kern() and thus they aren't marked as for-kernel, though they appear to be internal. I wonder if these should do that so that they use the new set of lock keys. Signed-off-by: David Howells Signed-off-by: David S. Miller

sched/headers: Move task_struct::signal and task_struct::sighand types and accessors into

2017-03-03T00:43:37Z

task_struct::signal and task_struct::sighand are pointers, which would normally make it straightforward to not define those types in sched.h. That is not so, because the types are accompanied by a myriad of APIs (macros and inline functions) that dereference them. Split the types and the APIs out of sched.h and move them into a new header, . With this change sched.h does not know about 'struct signal' and 'struct sighand' anymore, trying to put accessors into sched.h as a test fails the following way: ./include/linux/sched.h: In function ‘test_signal_types’: ./include/linux/sched.h:2461:18: error: dereferencing pointer to incomplete type ‘struct signal_struct’ ^ This reduces the size and complexity of sched.h significantly. Update all headers and .c code that relied on getting the signal handling functionality from to include . The list of affected files in the preparatory patch was partly generated by grepping for the APIs, and partly by doing coverage build testing, both all[yes|mod|def|no]config builds on 64-bit and 32-bit x86, and an array of cross-architecture builds. Nevertheless some (trivial) build breakage is still expected related to rare Kconfig combinations and in-flight patches to various kernel code, but most of it should be handled by this patch. Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar

smc: some potential use after free bugs

2017-01-30T21:37:55Z

Say we got really unlucky and these failed on the last iteration, then it could lead to a use after free bug. Fixes: cd6851f30386 ("smc: remote memory buffers (RMBs)") Signed-off-by: Dan Carpenter Signed-off-by: Ursula Braun Signed-off-by: David S. Miller

smc: ETH_ALEN as memcpy length for mac addresses

2017-01-12T14:47:01Z

When creating an SMC connection, there is a CLC (connection layer control) handshake to prepare for RDMA traffic. The corresponding code is part of commit 0cfdd8f92cac ("smc: connection and link group creation"). Mac addresses to be exchanged in the handshake are copied with a wrong length of 12 instead of 6 bytes. Following code overwrites the wrongly copied code, but nevertheless the correct length should already be used for the preceding mac address copying. Use ETH_ALEN for the memcpy length with mac addresses. Signed-off-by: Ursula Braun Fixes: 0cfdd8f92cac ("smc: connection and link group creation") Reported-by: Dan Carpenter Signed-off-by: David S. Miller

smc: netlink interface for SMC sockets

2017-01-09T21:07:41Z

Support for SMC socket monitoring via netlink sockets of protocol NETLINK_SOCK_DIAG. Signed-off-by: Ursula Braun Signed-off-by: David S. Miller

smc: socket closing and linkgroup cleanup

2017-01-09T21:07:40Z

smc_shutdown() and smc_release() handling delayed linkgroup cleanup for linkgroups without connections Signed-off-by: Ursula Braun Signed-off-by: David S. Miller

smc: receive data from RMBE

2017-01-09T21:07:40Z

move RMBE data into user space buffer and update managing cursors Signed-off-by: Ursula Braun Signed-off-by: David S. Miller

smc: send data (through RDMA)

2017-01-09T21:07:40Z

copy data to kernel send buffer, and trigger RDMA write Signed-off-by: Ursula Braun Signed-off-by: David S. Miller