kernel/linux.git/net, branch v4.4.171

sunrpc: use-after-free in svc_process_common()

2019-01-16T21:16:12+00:00

commit d4b09acf924b84bae77cad090a9d108e70b43643 upstream. if node have NFSv41+ mounts inside several net namespaces it can lead to use-after-free in svc_process_common() svc_process_common() /* Setup reply header */ rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); <<< HERE svc_process_common() can use incorrect rqstp->rq_xprt, its caller function bc_svc_process() takes it from serv->sv_bc_xprt. The problem is that serv is global structure but sv_bc_xprt is assigned per-netnamespace. According to Trond, the whole "let's set up rqstp->rq_xprt for the back channel" is nothing but a giant hack in order to work around the fact that svc_process_common() uses it to find the xpt_ops, and perform a couple of (meaningless for the back channel) tests of xpt_flags. All we really need in svc_process_common() is to be able to run rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr() Bruce J Fields points that this xpo_prep_reply_hdr() call is an awfully roundabout way just to do "svc_putnl(resv, 0);" in the tcp case. This patch does not initialiuze rqstp->rq_xprt in bc_svc_process(), now it calls svc_process_common() with rqstp->rq_xprt = NULL. To adjust reply header svc_process_common() just check rqstp->rq_prot and calls svc_tcp_prep_reply_hdr() for tcp case. To handle rqstp->rq_xprt = NULL case in functions called from svc_process_common() patch intruduces net namespace pointer svc_rqst->rq_bc_net and adjust SVC_NET() definition. Some other function was also adopted to properly handle described case. Signed-off-by: Vasily Averin Cc: stable@vger.kernel.org Fixes: 23c20ecd4475 ("NFS: callback up - users counting cleanup") Signed-off-by: J. Bruce Fields v2: - added lost extern svc_tcp_prep_reply_hdr() - dropped trace_svc_process() changes - context fixes in svc_process_common() Signed-off-by: Vasily Averin Signed-off-by: Greg Kroah-Hartman

9p/net: put a lower bound on msize

2019-01-13T09:05:33+00:00

commit 574d356b7a02c7e1b01a1d9cba8a26b3c2888f45 upstream. If the requested msize is too small (either from command line argument or from the server version reply), we won't get any work done. If it's *really* too small, nothing will work, and this got caught by syzbot recently (on a new kmem_cache_create_usercopy() call) Just set a minimum msize to 4k in both code paths, until someone complains they have a use-case for a smaller msize. We need to check in both mount option and server reply individually because the msize for the first version request would be unchecked with just a global check on clnt->msize. Link: http://lkml.kernel.org/r/1541407968-31350-1-git-send-email-asmadeus@codewreck.org Reported-by: syzbot+0c1d61e4db7db94102ca@syzkaller.appspotmail.com Signed-off-by: Dominique Martinet Cc: Eric Van Hensbergen Cc: Latchesar Ionkov Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

sunrpc: use SVC_NET() in svcauth_gss_* functions

2019-01-13T09:05:32+00:00

commit b8be5674fa9a6f3677865ea93f7803c4212f3e10 upstream. Signed-off-by: Vasily Averin Cc: stable@vger.kernel.org Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman

sunrpc: fix cache_head leak due to queued request

2019-01-13T09:05:32+00:00

commit 4ecd55ea074217473f94cfee21bb72864d39f8d7 upstream. After commit d202cce8963d, an expired cache_head can be removed from the cache_detail's hash. However, the expired cache_head may be waiting for a reply from a previously submitted request. Such a cache_head has an increased refcounter and therefore it won't be freed after cache_put(freeme). Because the cache_head was removed from the hash it cannot be found during cache_clean() and can be leaked forever, together with stalled cache_request and other taken resources. In our case we noticed it because an entry in the export cache was holding a reference on a filesystem. Fixes d202cce8963d ("sunrpc: never return expired entries in sunrpc_cache_lookup") Cc: Pavel Tikhomirov Cc: stable@kernel.org # 2.6.35 Signed-off-by: Vasily Averin Reviewed-by: NeilBrown Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman

xfrm: Fix bucket count reported to userspace

2019-01-13T09:05:31+00:00

[ Upstream commit ca92e173ab34a4f7fc4128bd372bd96f1af6f507 ] sadhcnt is reported by `ip -s xfrm state count` as "buckets count", not the hash mask. Fixes: 28d8909bc790 ("[XFRM]: Export SAD info.") Signed-off-by: Benjamin Poirier Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin

sock: Make sock->sk_stamp thread-safe

2019-01-13T09:05:28+00:00

[ Upstream commit 3a0ed3e9619738067214871e9cb826fa23b2ddb9 ] Al Viro mentioned (Message-ID <20170626041334.GZ10672@ZenIV.linux.org.uk>) that there is probably a race condition lurking in accesses of sk_stamp on 32-bit machines. sock->sk_stamp is of type ktime_t which is always an s64. On a 32 bit architecture, we might run into situations of unsafe access as the access to the field becomes non atomic. Use seqlocks for synchronization. This allows us to avoid using spinlocks for readers as readers do not need mutual exclusion. Another approach to solve this is to require sk_lock for all modifications of the timestamps. The current approach allows for timestamps to have their own lock: sk_stamp_lock. This allows for the patch to not compete with already existing critical sections, and side effects are limited to the paths in the patch. The addition of the new field maintains the data locality optimizations from commit 9115e8cd2a0c ("net: reorganize struct sock for better data locality") Note that all the instances of the sk_stamp accesses are either through the ioctl or the syscall recvmsg. Signed-off-by: Deepa Dinamani Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

VSOCK: Send reset control packet when socket is partially bound

2019-01-13T09:05:28+00:00

[ Upstream commit a915b982d8f5e4295f64b8dd37ce753874867e88 ] If a server side socket is bound to an address, but not in the listening state yet, incoming connection requests should receive a reset control packet in response. However, the function used to send the reset silently drops the reset packet if the sending socket isn't bound to a remote address (as is the case for a bound socket not yet in the listening state). This change fixes this by using the src of the incoming packet as destination for the reset packet in this case. Fixes: d021c344051a ("VSOCK: Introduce VM Sockets") Reviewed-by: Adit Ranadive Reviewed-by: Vishnu Dasa Signed-off-by: Jorgen Hansen Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sctp: initialize sin6_flowinfo for ipv6 addrs in sctp_inet6addr_event

2019-01-13T09:05:28+00:00

[ Upstream commit 4a2eb0c37b4759416996fbb4c45b932500cf06d3 ] syzbot reported a kernel-infoleak, which is caused by an uninitialized field(sin6_flowinfo) of addr->a.v6 in sctp_inet6addr_event(). The call trace is as below: BUG: KMSAN: kernel-infoleak in _copy_to_user+0x19a/0x230 lib/usercopy.c:33 CPU: 1 PID: 8164 Comm: syz-executor2 Not tainted 4.20.0-rc3+ #95 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x32d/0x480 lib/dump_stack.c:113 kmsan_report+0x12c/0x290 mm/kmsan/kmsan.c:683 kmsan_internal_check_memory+0x32a/0xa50 mm/kmsan/kmsan.c:743 kmsan_copy_to_user+0x78/0xd0 mm/kmsan/kmsan_hooks.c:634 _copy_to_user+0x19a/0x230 lib/usercopy.c:33 copy_to_user include/linux/uaccess.h:183 [inline] sctp_getsockopt_local_addrs net/sctp/socket.c:5998 [inline] sctp_getsockopt+0x15248/0x186f0 net/sctp/socket.c:7477 sock_common_getsockopt+0x13f/0x180 net/core/sock.c:2937 __sys_getsockopt+0x489/0x550 net/socket.c:1939 __do_sys_getsockopt net/socket.c:1950 [inline] __se_sys_getsockopt+0xe1/0x100 net/socket.c:1947 __x64_sys_getsockopt+0x62/0x80 net/socket.c:1947 do_syscall_64+0xcf/0x110 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 sin6_flowinfo is not really used by SCTP, so it will be fixed by simply setting it to 0. The issue exists since very beginning. Thanks Alexander for the reproducer provided. Reported-by: syzbot+ad5d327e6936a2e284be@syzkaller.appspotmail.com Signed-off-by: Xin Long Acked-by: Marcelo Ricardo Leitner Acked-by: Neil Horman Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

packet: validate address length if non-zero

2019-01-13T09:05:28+00:00

[ Upstream commit 6b8d95f1795c42161dc0984b6863e95d6acf24ed ] Validate packet socket address length if a length is given. Zero length is equivalent to not setting an address. Fixes: 99137b7888f4 ("packet: validate address length") Reported-by: Ido Schimmel Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

packet: validate address length

2019-01-13T09:05:28+00:00

[ Upstream commit 99137b7888f4058087895d035d81c6b2d31015c5 ] Packet sockets with SOCK_DGRAM may pass an address for use in dev_hard_header. Ensure that it is of sufficient length. Reported-by: syzbot Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman