BMC/Intel-BMC/linux.git/drivers/connector/cn_proc.c, branch v5.2

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

2019-05-30T18:26:35+00:00

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 59 temple place suite 330 boston ma 02111 1307 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1334 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Allison Randal Reviewed-by: Richard Fontana Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de Signed-off-by: Greg Kroah-Hartman

connector: fix unsafe usage of ->real_parent

2019-03-08T23:06:38+00:00

proc_exit_connector() uses ->real_parent lockless. This is not safe that its parent can go away at any moment, so use RCU to protect it, and ensure that this task is not released. [ 747.624551] ================================================================== [ 747.632946] BUG: KASAN: use-after-free in proc_exit_connector+0x1f7/0x310 [ 747.640686] Read of size 4 at addr ffff88a0276988e0 by task sshd/2882 [ 747.648032] [ 747.649804] CPU: 11 PID: 2882 Comm: sshd Tainted: G E 4.19.26-rc2 #11 [ 747.658629] Hardware name: IBM x3550M4 -[7914OFV]-/00AM544, BIOS -[D7E142BUS-1.71]- 07/31/2014 [ 747.668419] Call Trace: [ 747.671269] dump_stack+0xf0/0x19b [ 747.675186] ? show_regs_print_info+0x5/0x5 [ 747.679988] ? kmsg_dump_rewind_nolock+0x59/0x59 [ 747.685302] print_address_description+0x6a/0x270 [ 747.691162] kasan_report+0x258/0x380 [ 747.695835] ? proc_exit_connector+0x1f7/0x310 [ 747.701402] proc_exit_connector+0x1f7/0x310 [ 747.706767] ? proc_coredump_connector+0x2d0/0x2d0 [ 747.712715] ? _raw_write_unlock_irq+0x29/0x50 [ 747.718270] ? _raw_write_unlock_irq+0x29/0x50 [ 747.723820] ? ___preempt_schedule+0x16/0x18 [ 747.729193] ? ___preempt_schedule+0x16/0x18 [ 747.734574] do_exit+0xa11/0x14f0 [ 747.738880] ? mm_update_next_owner+0x590/0x590 [ 747.744525] ? debug_show_all_locks+0x3c0/0x3c0 [ 747.761448] ? ktime_get_coarse_real_ts64+0xeb/0x1c0 [ 747.767589] ? lockdep_hardirqs_on+0x1a6/0x290 [ 747.773154] ? check_chain_key+0x139/0x1f0 [ 747.778345] ? check_flags.part.35+0x240/0x240 [ 747.783908] ? __lock_acquire+0x2300/0x2300 [ 747.789171] ? _raw_spin_unlock_irqrestore+0x59/0x70 [ 747.795316] ? _raw_spin_unlock_irqrestore+0x59/0x70 [ 747.801457] ? do_raw_spin_unlock+0x10f/0x1e0 [ 747.806914] ? do_raw_spin_trylock+0x120/0x120 [ 747.812481] ? preempt_count_sub+0x14/0xc0 [ 747.817645] ? _raw_spin_unlock+0x2e/0x50 [ 747.822708] ? __handle_mm_fault+0x12db/0x1fa0 [ 747.828367] ? __pmd_alloc+0x2d0/0x2d0 [ 747.833143] ? check_noncircular+0x50/0x50 [ 747.838309] ? match_held_lock+0x7f/0x340 [ 747.843380] ? check_noncircular+0x50/0x50 [ 747.848561] ? handle_mm_fault+0x21a/0x5f0 [ 747.853730] ? check_flags.part.35+0x240/0x240 [ 747.859290] ? check_chain_key+0x139/0x1f0 [ 747.864474] ? __do_page_fault+0x40f/0x760 [ 747.869655] ? __audit_syscall_entry+0x4b/0x1f0 [ 747.875319] ? syscall_trace_enter+0x1d5/0x7b0 [ 747.880877] ? trace_raw_output_preemptirq_template+0x90/0x90 [ 747.887895] ? trace_raw_output_sys_exit+0x80/0x80 [ 747.893860] ? up_read+0x3b/0x90 [ 747.898142] ? stop_critical_timings+0x260/0x260 [ 747.903909] do_group_exit+0xe0/0x1c0 [ 747.908591] ? __x64_sys_exit+0x30/0x30 [ 747.913460] ? trace_raw_output_preemptirq_template+0x90/0x90 [ 747.920485] ? tracer_hardirqs_on+0x270/0x270 [ 747.925956] __x64_sys_exit_group+0x28/0x30 [ 747.931214] do_syscall_64+0x117/0x400 [ 747.935988] ? syscall_return_slowpath+0x2f0/0x2f0 [ 747.941931] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 747.947788] ? trace_hardirqs_on_caller+0x1d0/0x1d0 [ 747.953838] ? lockdep_sys_exit+0x16/0x8e [ 747.958915] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 747.964784] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 747.971021] RIP: 0033:0x7f572f154c68 [ 747.975606] Code: Bad RIP value. [ 747.979791] RSP: 002b:00007ffed2dfaa58 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 747.989324] RAX: ffffffffffffffda RBX: 00007f572f431840 RCX: 00007f572f154c68 [ 747.997910] RDX: 0000000000000001 RSI: 000000000000003c RDI: 0000000000000001 [ 748.006495] RBP: 0000000000000001 R08: 00000000000000e7 R09: fffffffffffffee0 [ 748.015079] R10: 00007f572f4387e8 R11: 0000000000000246 R12: 00007f572f431840 [ 748.023664] R13: 000055a7f90f2c50 R14: 000055a7f96e2310 R15: 000055a7f96e2310 [ 748.032287] [ 748.034509] Allocated by task 2300: [ 748.038982] kasan_kmalloc+0xa0/0xd0 [ 748.043562] kmem_cache_alloc_node+0xf5/0x2e0 [ 748.049018] copy_process+0x1781/0x4790 [ 748.053884] _do_fork+0x166/0x9a0 [ 748.058163] do_syscall_64+0x117/0x400 [ 748.062943] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 748.069180] [ 748.071405] Freed by task 15395: [ 748.075591] __kasan_slab_free+0x130/0x180 [ 748.080752] kmem_cache_free+0xc2/0x310 [ 748.085619] free_task+0xea/0x130 [ 748.089901] __put_task_struct+0x177/0x230 [ 748.095063] finish_task_switch+0x51b/0x5d0 [ 748.100315] __schedule+0x506/0xfa0 [ 748.104791] schedule+0xca/0x260 [ 748.108978] futex_wait_queue_me+0x27e/0x420 [ 748.114333] futex_wait+0x251/0x550 [ 748.118814] do_futex+0x75b/0xf80 [ 748.123097] __x64_sys_futex+0x231/0x2a0 [ 748.128065] do_syscall_64+0x117/0x400 [ 748.132835] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 748.139066] [ 748.141289] The buggy address belongs to the object at ffff88a027698000 [ 748.141289] which belongs to the cache task_struct of size 12160 [ 748.156589] The buggy address is located 2272 bytes inside of [ 748.156589] 12160-byte region [ffff88a027698000, ffff88a02769af80) [ 748.171114] The buggy address belongs to the page: [ 748.177055] page:ffffea00809da600 count:1 mapcount:0 mapping:ffff888107d01e00 index:0x0 compound_mapcount: 0 [ 748.189136] flags: 0x57ffffc0008100(slab|head) [ 748.194688] raw: 0057ffffc0008100 ffffea00809a3200 0000000300000003 ffff888107d01e00 [ 748.204424] raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000 [ 748.214146] page dumped because: kasan: bad access detected [ 748.220976] [ 748.223197] Memory state around the buggy address: [ 748.229128] ffff88a027698780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 748.238271] ffff88a027698800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 748.247414] >ffff88a027698880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 748.256564] ^ [ 748.264267] ffff88a027698900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 748.273493] ffff88a027698980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 748.282630] ================================================================== Fixes: b086ff87251b4a4 ("connector: add parent pid and tgid to coredump and exit events") Signed-off-by: Zhang Yu Signed-off-by: Li RongQing Acked-by: Evgeniy Polyakov Signed-off-by: David S. Miller

connector: add parent pid and tgid to coredump and exit events

2018-05-01T18:25:37+00:00

The intention is to get notified of process failures as soon as possible, before a possible core dumping (which could be very long) (e.g. in some process-manager). Coredump and exit process events are perfect for such use cases (see 2b5faa4c553f "connector: Added coredumping event to the process connector"). The problem is that for now the process-manager cannot know the parent of a dying process using connectors. This could be useful if the process-manager should monitor for failures only children of certain parents, so we could filter the coredump and exit events by parent process and/or thread ID. Add parent pid and tgid to coredump and exit process connectors event data. Signed-off-by: Stefan Strogin Acked-by: Evgeniy Polyakov Signed-off-by: David S. Miller

connector: make cn_proc explicitly non-modular

2016-07-05T18:40:47+00:00

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

2016-06-28T12:48:33+00:00

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: Use ktime_get_ns()

2014-07-23T17:18:07+00:00

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

net: Use netlink_ns_capable to verify the permisions of netlink messages

2014-04-24T17:44:54+00:00

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

connector: add portid to unicast in addition to broadcasting

2014-02-07T23:40:17+00:00

This allows replying only to the requestor portid while still supporting broadcasting. Pass 0 to portid for the previous behavior. Signed-off-by: David Fries Acked-by: Evgeniy Polyakov Signed-off-by: Greg Kroah-Hartman

connector: improved unaligned access error fix

2013-11-14T22:19:20+00:00

In af3e095a1fb4, Erik Jacobsen fixed one type of unaligned access bug for ia64 by converting a 64-bit write to use put_unaligned(). Unfortunately, since gcc will convert a short memset() to a series of appropriately-aligned stores, the problem is now visible again on tilegx, where the memset that zeros out proc_event is converted to three 64-bit stores, causing an unaligned access panic. A better fix for the original problem is to ensure that proc_event is aligned to 8 bytes here. We can do that relatively easily by arranging to start the struct cn_msg aligned to 8 bytes and then offset by 4 bytes. Doing so means that the immediately following proc_event structure is then correctly aligned to 8 bytes. The result is that the memset() stores are now aligned, and as an added benefit, we can remove the put_unaligned() calls in the code. Signed-off-by: Chris Metcalf Signed-off-by: David S. Miller

proc connector: fix info leaks

2013-10-02T20:03:50+00:00

Initialize event_data for all possible message types to prevent leaking kernel stack contents to userland (up to 20 bytes). Also set the flags member of the connector message to 0 to prevent leaking two more stack bytes this way. Cc: stable@vger.kernel.org # v2.6.15+ Signed-off-by: Mathias Krause Signed-off-by: David S. Miller