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2018-05-26net: remove sock_no_pollChristoph Hellwig
Now that sock_poll handles a NULL ->poll or ->poll_mask there is no need for a stub. Signed-off-by: Christoph Hellwig <hch@lst.de>
2018-01-12crypto: hash - prevent using keyed hashes without setting keyEric Biggers
Currently, almost none of the keyed hash algorithms check whether a key has been set before proceeding. Some algorithms are okay with this and will effectively just use a key of all 0's or some other bogus default. However, others will severely break, as demonstrated using "hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash via a (potentially exploitable) stack buffer overflow. A while ago, this problem was solved for AF_ALG by pairing each hash transform with a 'has_key' bool. However, there are still other places in the kernel where userspace can specify an arbitrary hash algorithm by name, and the kernel uses it as unkeyed hash without checking whether it is really unkeyed. Examples of this include: - KEYCTL_DH_COMPUTE, via the KDF extension - dm-verity - dm-crypt, via the ESSIV support - dm-integrity, via the "internal hash" mode with no key given - drbd (Distributed Replicated Block Device) This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no privileges to call. Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the ->crt_flags of each hash transform that indicates whether the transform still needs to be keyed or not. Then, make the hash init, import, and digest functions return -ENOKEY if the key is still needed. The new flag also replaces the 'has_key' bool which algif_hash was previously using, thereby simplifying the algif_hash implementation. Reported-by: syzbot <syzkaller@googlegroups.com> Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-03crypto: algif - move to generic async completionGilad Ben-Yossef
algif starts several async crypto ops and waits for their completion. Move it over to generic code doing the same. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-03-09net: Work around lockdep limitation in sockets that use socketsDavid Howells
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 <dhowells@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-12-27crypto: algif_hash - avoid zero-sized arrayJiri Slaby
With this reproducer: struct sockaddr_alg alg = { .salg_family = 0x26, .salg_type = "hash", .salg_feat = 0xf, .salg_mask = 0x5, .salg_name = "digest_null", }; int sock, sock2; sock = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(sock, (struct sockaddr *)&alg, sizeof(alg)); sock2 = accept(sock, NULL, NULL); setsockopt(sock, SOL_ALG, ALG_SET_KEY, "\x9b\xca", 2); accept(sock2, NULL, NULL); ==== 8< ======== 8< ======== 8< ======== 8< ==== one can immediatelly see an UBSAN warning: UBSAN: Undefined behaviour in crypto/algif_hash.c:187:7 variable length array bound value 0 <= 0 CPU: 0 PID: 15949 Comm: syz-executor Tainted: G E 4.4.30-0-default #1 ... Call Trace: ... [<ffffffff81d598fd>] ? __ubsan_handle_vla_bound_not_positive+0x13d/0x188 [<ffffffff81d597c0>] ? __ubsan_handle_out_of_bounds+0x1bc/0x1bc [<ffffffffa0e2204d>] ? hash_accept+0x5bd/0x7d0 [algif_hash] [<ffffffffa0e2293f>] ? hash_accept_nokey+0x3f/0x51 [algif_hash] [<ffffffffa0e206b0>] ? hash_accept_parent_nokey+0x4a0/0x4a0 [algif_hash] [<ffffffff8235c42b>] ? SyS_accept+0x2b/0x40 It is a correct warning, as hash state is propagated to accept as zero, but creating a zero-length variable array is not allowed in C. Fix this as proposed by Herbert -- do "?: 1" on that site. No sizeof or similar happens in the code there, so we just allocate one byte even though we do not use the array. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> (maintainer:CRYPTO API) Reported-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-22crypto: algif_hash - Fix result clobbering in recvmsgHerbert Xu
Recently an init call was added to hash_recvmsg so as to reset the hash state in case a sendmsg call was never made. Unfortunately this ended up clobbering the result if the previous sendmsg was done with a MSG_MORE flag. This patch fixes it by excluding that case when we make the init call. Fixes: a8348bca2944 ("algif_hash - Fix NULL hash crash with shash") Reported-by: Patrick Steinhardt <ps@pks.im> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-18crypto: algif_hash - Fix NULL hash crash with shashHerbert Xu
Recently algif_hash has been changed to allow null hashes. This triggers a bug when used with an shash algorithm whereby it will cause a crash during the digest operation. This patch fixes it by avoiding the digest operation and instead doing an init followed by a final which avoids the buggy code in shash. This patch also ensures that the result buffer is freed after an error so that it is not returned as a genuine hash result on the next recv call. The shash/ahash wrapper code will be fixed later to handle this case correctly. Fixes: 493b2ed3f760 ("crypto: algif_hash - Handle NULL hashes correctly") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Laura Abbott <labbott@redhat.com>
2016-09-07crypto: algif_hash - Handle NULL hashes correctlyHerbert Xu
Right now attempting to read an empty hash simply returns zeroed bytes, this patch corrects this by calling the digest function using an empty input. Reported-by: Russell King - ARM Linux <linux@armlinux.org.uk> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-30crypto: algif_hash - wait for crypto_ahash_init() to completeWang, Rui Y
hash_sendmsg/sendpage() need to wait for the completion of crypto_ahash_init() otherwise it can cause panic. Cc: stable@vger.kernel.org Signed-off-by: Rui Wang <rui.y.wang@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-18crypto: algif_hash - Fix race condition in hash_check_keyHerbert Xu
We need to lock the child socket in hash_check_key as otherwise two simultaneous calls can cause the parent socket to be freed. Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-18crypto: algif_hash - Remove custom release parent functionHerbert Xu
This patch removes the custom release parent function as the generic af_alg_release_parent now works for nokey sockets too. Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-18crypto: algif_hash - Require setkey before accept(2)Herbert Xu
Hash implementations that require a key may crash if you use them without setting a key. This patch adds the necessary checks so that if you do attempt to use them without a key that we return -ENOKEY instead of proceeding. This patch also adds a compatibility path to support old applications that do acept(2) before setkey. Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-11-02crypto: algif_hash - Only export and import on sockets with dataHerbert Xu
The hash_accept call fails to work on sockets that have not received any data. For some algorithm implementations it may cause crashes. This patch fixes this by ensuring that we only export and import on sockets that have received data. Cc: stable@vger.kernel.org Reported-by: Harsh Jain <harshjain.prof@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Stephan Mueller <smueller@chronox.de>
2015-04-11new helper: msg_data_left()Al Viro
convert open-coded instances Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-02net: Remove iocb argument from sendmsg and recvmsgYing Xue
After TIPC doesn't depend on iocb argument in its internal implementations of sendmsg() and recvmsg() hooks defined in proto structure, no any user is using iocb argument in them at all now. Then we can drop the redundant iocb argument completely from kinds of implementations of both sendmsg() and recvmsg() in the entire networking stack. Cc: Christoph Hellwig <hch@lst.de> Suggested-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Ying Xue <ying.xue@windriver.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-04crypto: switch af_alg_make_sg() to iov_iterAl Viro
With that, all ->sendmsg() instances are converted to iov_iter primitives and are agnostic wrt the kind of iov_iter they are working with. So's the last remaining ->recvmsg() instance that wasn't kind-agnostic yet. All ->sendmsg() and ->recvmsg() advance ->msg_iter by the amount actually copied and none of them modifies the underlying iovec, etc. Cc: linux-crypto@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-13Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds
Pull crypto update from Herbert Xu: - The crypto API is now documented :) - Disallow arbitrary module loading through crypto API. - Allow get request with empty driver name through crypto_user. - Allow speed testing of arbitrary hash functions. - Add caam support for ctr(aes), gcm(aes) and their derivatives. - nx now supports concurrent hashing properly. - Add sahara support for SHA1/256. - Add ARM64 version of CRC32. - Misc fixes. * git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (77 commits) crypto: tcrypt - Allow speed testing of arbitrary hash functions crypto: af_alg - add user space interface for AEAD crypto: qat - fix problem with coalescing enable logic crypto: sahara - add support for SHA1/256 crypto: sahara - replace tasklets with kthread crypto: sahara - add support for i.MX53 crypto: sahara - fix spinlock initialization crypto: arm - replace memset by memzero_explicit crypto: powerpc - replace memset by memzero_explicit crypto: sha - replace memset by memzero_explicit crypto: sparc - replace memset by memzero_explicit crypto: algif_skcipher - initialize upon init request crypto: algif_skcipher - removed unneeded code crypto: algif_skcipher - Fixed blocking recvmsg crypto: drbg - use memzero_explicit() for clearing sensitive data crypto: drbg - use MODULE_ALIAS_CRYPTO crypto: include crypto- module prefix in template crypto: user - add MODULE_ALIAS crypto: sha-mb - remove a bogus NULL check crytpo: qat - Fix 64 bytes requests ...
2014-12-09put iov_iter into msghdrAl Viro
Note that the code _using_ ->msg_iter at that point will be very unhappy with anything other than unshifted iovec-backed iov_iter. We still need to convert users to proper primitives. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-25crypto: algif - add and use sock_kzfree_s() instead of memzero_explicit()Daniel Borkmann
Commit e1bd95bf7c25 ("crypto: algif - zeroize IV buffer") and 2a6af25befd0 ("crypto: algif - zeroize message digest buffer") added memzero_explicit() calls on buffers that are later on passed back to sock_kfree_s(). This is a discussed follow-up that, instead, extends the sock API and adds sock_kzfree_s(), which internally uses kzfree() instead of kfree() for passing the buffers back to slab. Having sock_kzfree_s() allows to keep the changes more minimal by just having a drop-in replacement instead of adding memzero_explicit() calls everywhere before sock_kfree_s(). In kzfree(), the compiler is not allowed to optimize the memset() away and thus there's no need for memzero_explicit(). Both, sock_kfree_s() and sock_kzfree_s() are wrappers for __sock_kfree_s() and call into kfree() resp. kzfree(); here, __sock_kfree_s() needs to be explicitly inlined as we want the compiler to optimize the call and condition away and thus it produces e.g. on x86_64 the _same_ assembler output for sock_kfree_s() before and after, and thus also allows for avoiding code duplication. Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-24new helper: memcpy_to_msg()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-11-12crypto: algif - zeroize message digest bufferStephan Mueller
Zeroize the buffer holding the message digest calculated for the consumer before the buffer is released by the hash AF_ALG interface handler. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-11-29net: update consumers of MSG_MORE to recognize MSG_SENDPAGE_NOTLASTShawn Landden
Commit 35f9c09fe (tcp: tcp_sendpages() should call tcp_push() once) added an internal flag MSG_SENDPAGE_NOTLAST, similar to MSG_MORE. algif_hash, algif_skcipher, and udp used MSG_MORE from tcp_sendpages() and need to see the new flag as identical to MSG_MORE. This fixes sendfile() on AF_ALG. v3: also fix udp Cc: Tom Herbert <therbert@google.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Cc: David S. Miller <davem@davemloft.net> Cc: <stable@vger.kernel.org> # 3.4.x + 3.2.x Reported-and-tested-by: Shawn Landden <shawnlandden@gmail.com> Original-patch: Richard Weinberger <richard@nod.at> Signed-off-by: Shawn Landden <shawn@churchofgit.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-20net: rework recvmsg handler msg_name and msg_namelen logicHannes Frederic Sowa
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>
2013-04-10crypto: algif - suppress sending source address information in recvmsgMathias Krause
The current code does not set the msg_namelen member to 0 and therefore makes net/socket.c leak the local sockaddr_storage variable to userland -- 128 bytes of kernel stack memory. Fix that. Cc: <stable@vger.kernel.org> # 2.6.38 Signed-off-by: Mathias Krause <minipli@googlemail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-06-30crypto: algif_hash - Handle initial af_alg_make_sg error correctlyHerbert Xu
When the first call to af_alg_make_sg fails, we may return garbage instead of the real error. This patch fixes it by setting the error if "copied" is zero. Based on a patch by Jesper Juhl. Reported-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-11-19crypto: algif_hash - User-space interface for hash operationsHerbert Xu
This patch adds the af_alg plugin for hash, corresponding to the ahash kernel operation type. Keys can optionally be set through the setsockopt interface. Each sendmsg call will finalise the hash unless sent with a MSG_MORE flag. Partial hash states can be cloned using accept(2). The interface is completely synchronous, all operations will complete prior to the system call returning. Both sendmsg(2) and splice(2) support reading the user-space data directly without copying (except that the Crypto API itself may copy the data if alignment is off). For now only the splice(2) interface supports performing digest instead of init/update/final. In future the sendmsg(2) interface will also be modified to use digest/finup where possible so that hardware that cannot return a partial hash state can still benefit from this interface. Thakns to Miloslav Trmac for reviewing this and contributing fixes and improvements. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: David S. Miller <davem@davemloft.net> Tested-by: Martin Willi <martin@strongswan.org>