linux/drivers/connector, branch v4.9

connector: make cn_proc explicitly non-modular

2016-07-05T18:40:47Z

The Kconfig controlling build of this code is currently: drivers/connector/Kconfig:config PROC_EVENTS drivers/connector/Kconfig: bool "Report process events to userspace" ...meaning that it currently is not being built as a module by anyone. Lets remove the two modular references, so that when reading the driver there is no doubt it is builtin-only. Since module_init translates to device_initcall in the non-modular case, the init ordering remains unchanged with this commit. Cc: Evgeniy Polyakov Cc: netdev@vger.kernel.org Signed-off-by: Paul Gortmaker Signed-off-by: David S. Miller

connector: fix out-of-order cn_proc netlink message delivery

2016-06-28T12:48:33Z

The proc connector messages include a sequence number, allowing userspace programs to detect lost messages. However, performing this detection is currently more difficult than necessary, since netlink messages can be delivered to the application out-of-order. To fix this, leave pre-emption disabled during cn_netlink_send(), and use GFP_NOWAIT. The following was written as a test case. Building the kernel w/ make -j32 proved a reliable way to generate out-of-order cn_proc messages. int main(int argc, char *argv[]) { static uint32_t last_seq[CPU_SETSIZE], seq; int cpu, fd; struct sockaddr_nl sa; struct __attribute__((aligned(NLMSG_ALIGNTO))) { struct nlmsghdr nl_hdr; struct __attribute__((__packed__)) { struct cn_msg cn_msg; struct proc_event cn_proc; }; } rmsg; struct __attribute__((aligned(NLMSG_ALIGNTO))) { struct nlmsghdr nl_hdr; struct __attribute__((__packed__)) { struct cn_msg cn_msg; enum proc_cn_mcast_op cn_mcast; }; } smsg; fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR); if (fd < 0) { perror("socket"); } sa.nl_family = AF_NETLINK; sa.nl_groups = CN_IDX_PROC; sa.nl_pid = getpid(); if (bind(fd, (struct sockaddr *)&sa, sizeof(sa)) < 0) { perror("bind"); } memset(&smsg, 0, sizeof(smsg)); smsg.nl_hdr.nlmsg_len = sizeof(smsg); smsg.nl_hdr.nlmsg_pid = getpid(); smsg.nl_hdr.nlmsg_type = NLMSG_DONE; smsg.cn_msg.id.idx = CN_IDX_PROC; smsg.cn_msg.id.val = CN_VAL_PROC; smsg.cn_msg.len = sizeof(enum proc_cn_mcast_op); smsg.cn_mcast = PROC_CN_MCAST_LISTEN; if (send(fd, &smsg, sizeof(smsg), 0) != sizeof(smsg)) { perror("send"); } while (recv(fd, &rmsg, sizeof(rmsg), 0) == sizeof(rmsg)) { cpu = rmsg.cn_proc.cpu; if (cpu < 0) { continue; } seq = rmsg.cn_msg.seq; if ((last_seq[cpu] != 0) && (seq != last_seq[cpu] + 1)) { printf("out-of-order seq=%d on cpu=%d\n", seq, cpu); } last_seq[cpu] = seq; } /* NOTREACHED */ perror("recv"); return -1; } Signed-off-by: Aaron Campbell Signed-off-by: David S. Miller

connector: bump skb->users before callback invocation

2016-01-05T02:46:45Z

Dmitry reports memleak with syskaller program. Problem is that connector bumps skb usecount but might not invoke callback. So move skb_get to where we invoke the callback. Reported-by: Dmitry Vyukov Signed-off-by: Florian Westphal Signed-off-by: David S. Miller

mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd

2015-11-07T01:50:42Z

__GFP_WAIT has been used to identify atomic context in callers that hold spinlocks or are in interrupts. They are expected to be high priority and have access one of two watermarks lower than "min" which can be referred to as the "atomic reserve". __GFP_HIGH users get access to the first lower watermark and can be called the "high priority reserve". Over time, callers had a requirement to not block when fallback options were available. Some have abused __GFP_WAIT leading to a situation where an optimisitic allocation with a fallback option can access atomic reserves. This patch uses __GFP_ATOMIC to identify callers that are truely atomic, cannot sleep and have no alternative. High priority users continue to use __GFP_HIGH. __GFP_DIRECT_RECLAIM identifies callers that can sleep and are willing to enter direct reclaim. __GFP_KSWAPD_RECLAIM to identify callers that want to wake kswapd for background reclaim. __GFP_WAIT is redefined as a caller that is willing to enter direct reclaim and wake kswapd for background reclaim. This patch then converts a number of sites o __GFP_ATOMIC is used by callers that are high priority and have memory pools for those requests. GFP_ATOMIC uses this flag. o Callers that have a limited mempool to guarantee forward progress clear __GFP_DIRECT_RECLAIM but keep __GFP_KSWAPD_RECLAIM. bio allocations fall into this category where kswapd will still be woken but atomic reserves are not used as there is a one-entry mempool to guarantee progress. o Callers that are checking if they are non-blocking should use the helper gfpflags_allow_blocking() where possible. This is because checking for __GFP_WAIT as was done historically now can trigger false positives. Some exceptions like dm-crypt.c exist where the code intent is clearer if __GFP_DIRECT_RECLAIM is used instead of the helper due to flag manipulations. o Callers that built their own GFP flags instead of starting with GFP_KERNEL and friends now also need to specify __GFP_KSWAPD_RECLAIM. The first key hazard to watch out for is callers that removed __GFP_WAIT and was depending on access to atomic reserves for inconspicuous reasons. In some cases it may be appropriate for them to use __GFP_HIGH. The second key hazard is callers that assembled their own combination of GFP flags instead of starting with something like GFP_KERNEL. They may now wish to specify __GFP_KSWAPD_RECLAIM. It's almost certainly harmless if it's missed in most cases as other activity will wake kswapd. Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka Acked-by: Michal Hocko Acked-by: Johannes Weiner Cc: Christoph Lameter Cc: David Rientjes Cc: Vitaly Wool Cc: Rik van Riel Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

kconfig: use bool instead of boolean for type definition attributes

2015-01-07T12:08:04Z

Support for keyword 'boolean' will be dropped later on. No functional change. Reference: http://lkml.kernel.org/r/cover.1418003065.git.cj@linux.com Signed-off-by: Christoph Jaeger Signed-off-by: Michal Marek

cn: verify msg->len before making callback

2014-11-27T03:09:01Z

The struct cn_msg len field comes from userspace and needs to be validated. More logical to do so here where the cn_msg pointer is pulled out of the sk_buff than the callback which is passed cn_msg * and might assume no validation is needed. Reported-by: Dan Carpenter Acked-by: Evgeniy Polyakov Signed-off-by: David Fries Signed-off-by: Greg Kroah-Hartman

connector: Use ktime_get_ns()

2014-07-23T17:18:07Z

Replace the ever recurring: ts = ktime_get_ts(); ns = timespec_to_ns(&ts); with ns = ktime_get_ns(); Signed-off-by: Thomas Gleixner Cc: Evgeniy Polyakov Signed-off-by: John Stultz

Merge tag 'char-misc-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc into next

2014-06-03T15:06:56Z

Pull char/misc driver patches from Greg KH: "Here is the big char / misc driver update for 3.16-rc1. Lots of different driver updates for a variety of different drivers and minor driver subsystems. All have been in linux-next with no reported issues" * tag 'char-misc-3.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (79 commits) hv: use correct order when freeing monitor_pages spmi: of: fixup generic SPMI devicetree binding example applicom: dereferencing NULL on error path misc: genwqe: fix uninitialized return value in genwqe_free_sync_sgl() miscdevice.h: Simple syntax fix to make pointers consistent. MAINTAINERS: Add miscdevice.h to file list for char/misc drivers. mcb: Add support for shared PCI IRQs drivers: Remove duplicate conditionally included subdirs misc: atmel_pwm: only build for supported platforms mei: me: move probe quirk to cfg structure mei: add per device configuration mei: me: read H_CSR after asserting reset mei: me: drop harmful wait optimization mei: me: fix hw ready reset flow mei: fix memory leak of mei_clients array uio: fix vma io range check in mmap drivers: uio_dmem_genirq: Fix memory leak in uio_dmem_genirq_probe() w1: do not unlock unheld list_mutex in __w1_remove_master_device() w1: optional bundling of netlink kernel replies connector: allow multiple messages to be sent in one packet ...

connector: allow multiple messages to be sent in one packet

2014-05-27T20:56:21Z

This increases the amount of bundling to reduce the number of packets sent. For the one wire use there can be multiple struct w1_netlink_cmd in a struct w1_netlink_msg and multiple of those in struct cn_msg, and with this change multiple of those in a struct nlmsghdr, and at each level the len identifies there being multiple of the next. Signed-off-by: David Fries Acked-by: Evgeniy Polyakov Signed-off-by: Greg Kroah-Hartman

net: Use netlink_ns_capable to verify the permisions of netlink messages

2014-04-24T17:44:54Z

It is possible by passing a netlink socket to a more privileged executable and then to fool that executable into writing to the socket data that happens to be valid netlink message to do something that privileged executable did not intend to do. To keep this from happening replace bare capable and ns_capable calls with netlink_capable, netlink_net_calls and netlink_ns_capable calls. Which act the same as the previous calls except they verify that the opener of the socket had the desired permissions as well. Reported-by: Andy Lutomirski Signed-off-by: "Eric W. Biederman" Signed-off-by: David S. Miller