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2020-08-21kprobes: Fix compiler warning for !CONFIG_KPROBES_ON_FTRACEMuchun Song
[ Upstream commit 10de795a5addd1962406796a6e13ba6cc0fc6bee ] Fix compiler warning(as show below) for !CONFIG_KPROBES_ON_FTRACE. kernel/kprobes.c: In function 'kill_kprobe': kernel/kprobes.c:1116:33: warning: statement with no effect [-Wunused-value] 1116 | #define disarm_kprobe_ftrace(p) (-ENODEV) | ^ kernel/kprobes.c:2154:3: note: in expansion of macro 'disarm_kprobe_ftrace' 2154 | disarm_kprobe_ftrace(p); Link: https://lore.kernel.org/r/20200805142136.0331f7ea@canb.auug.org.au Link: https://lkml.kernel.org/r/20200805172046.19066-1-songmuchun@bytedance.com Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Fixes: 0cb2f1372baa ("kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21sched/uclamp: Fix a deadlock when enabling uclamp static keyQais Yousef
[ Upstream commit e65855a52b479f98674998cb23b21ef5a8144b04 ] The following splat was caught when setting uclamp value of a task: BUG: sleeping function called from invalid context at ./include/linux/percpu-rwsem.h:49 cpus_read_lock+0x68/0x130 static_key_enable+0x1c/0x38 __sched_setscheduler+0x900/0xad8 Fix by ensuring we enable the key outside of the critical section in __sched_setscheduler() Fixes: 46609ce22703 ("sched/uclamp: Protect uclamp fast path code with static key") Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200716110347.19553-4-qais.yousef@arm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21sched/uclamp: Protect uclamp fast path code with static keyQais Yousef
[ Upstream commit 46609ce227039fd192e0ecc7d940bed587fd2c78 ] There is a report that when uclamp is enabled, a netperf UDP test regresses compared to a kernel compiled without uclamp. https://lore.kernel.org/lkml/20200529100806.GA3070@suse.de/ While investigating the root cause, there were no sign that the uclamp code is doing anything particularly expensive but could suffer from bad cache behavior under certain circumstances that are yet to be understood. https://lore.kernel.org/lkml/20200616110824.dgkkbyapn3io6wik@e107158-lin/ To reduce the pressure on the fast path anyway, add a static key that is by default will skip executing uclamp logic in the enqueue/dequeue_task() fast path until it's needed. As soon as the user start using util clamp by: 1. Changing uclamp value of a task with sched_setattr() 2. Modifying the default sysctl_sched_util_clamp_{min, max} 3. Modifying the default cpu.uclamp.{min, max} value in cgroup We flip the static key now that the user has opted to use util clamp. Effectively re-introducing uclamp logic in the enqueue/dequeue_task() fast path. It stays on from that point forward until the next reboot. This should help minimize the effect of util clamp on workloads that don't need it but still allow distros to ship their kernels with uclamp compiled in by default. SCHED_WARN_ON() in uclamp_rq_dec_id() was removed since now we can end up with unbalanced call to uclamp_rq_dec_id() if we flip the key while a task is running in the rq. Since we know it is harmless we just quietly return if we attempt a uclamp_rq_dec_id() when rq->uclamp[].bucket[].tasks is 0. In schedutil, we introduce a new uclamp_is_enabled() helper which takes the static key into account to ensure RT boosting behavior is retained. The following results demonstrates how this helps on 2 Sockets Xeon E5 2x10-Cores system. nouclamp uclamp uclamp-static-key Hmean send-64 162.43 ( 0.00%) 157.84 * -2.82%* 163.39 * 0.59%* Hmean send-128 324.71 ( 0.00%) 314.78 * -3.06%* 326.18 * 0.45%* Hmean send-256 641.55 ( 0.00%) 628.67 * -2.01%* 648.12 * 1.02%* Hmean send-1024 2525.28 ( 0.00%) 2448.26 * -3.05%* 2543.73 * 0.73%* Hmean send-2048 4836.14 ( 0.00%) 4712.08 * -2.57%* 4867.69 * 0.65%* Hmean send-3312 7540.83 ( 0.00%) 7425.45 * -1.53%* 7621.06 * 1.06%* Hmean send-4096 9124.53 ( 0.00%) 8948.82 * -1.93%* 9276.25 * 1.66%* Hmean send-8192 15589.67 ( 0.00%) 15486.35 * -0.66%* 15819.98 * 1.48%* Hmean send-16384 26386.47 ( 0.00%) 25752.25 * -2.40%* 26773.74 * 1.47%* The perf diff between nouclamp and uclamp-static-key when uclamp is disabled in the fast path: 8.73% -1.55% [kernel.kallsyms] [k] try_to_wake_up 0.07% +0.04% [kernel.kallsyms] [k] deactivate_task 0.13% -0.02% [kernel.kallsyms] [k] activate_task The diff between nouclamp and uclamp-static-key when uclamp is enabled in the fast path: 8.73% -0.72% [kernel.kallsyms] [k] try_to_wake_up 0.13% +0.39% [kernel.kallsyms] [k] activate_task 0.07% +0.38% [kernel.kallsyms] [k] deactivate_task Fixes: 69842cba9ace ("sched/uclamp: Add CPU's clamp buckets refcounting") Reported-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lkml.kernel.org/r/20200630112123.12076-3-qais.yousef@arm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-21module: Correctly truncate sysfs sections outputKees Cook
commit 11990a5bd7e558e9203c1070fc52fb6f0488e75b upstream. The only-root-readable /sys/module/$module/sections/$section files did not truncate their output to the available buffer size. While most paths into the kernfs read handlers end up using PAGE_SIZE buffers, it's possible to get there through other paths (e.g. splice, sendfile). Actually limit the output to the "count" passed into the read function, and report it back correctly. *sigh* Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/lkml/20200805002015.GE23458@shao2-debian Fixes: ed66f991bb19 ("module: Refactor section attr into bin attribute") Cc: stable@vger.kernel.org Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Jessica Yu <jeyu@kernel.org> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21tracing: Use trace_sched_process_free() instead of exit() for pid tracingSteven Rostedt (VMware)
commit afcab636657421f7ebfa0783a91f90256bba0091 upstream. On exit, if a process is preempted after the trace_sched_process_exit() tracepoint but before the process is done exiting, then when it gets scheduled in, the function tracers will not filter it properly against the function tracing pid filters. That is because the function tracing pid filters hooks to the sched_process_exit() tracepoint to remove the exiting task's pid from the filter list. Because the filtering happens at the sched_switch tracepoint, when the exiting task schedules back in to finish up the exit, it will no longer be in the function pid filtering tables. This was noticeable in the notrace self tests on a preemptable kernel, as the tests would fail as it exits and preempted after being taken off the notrace filter table and on scheduling back in it would not be in the notrace list, and then the ending of the exit function would trace. The test detected this and would fail. Cc: stable@vger.kernel.org Cc: Namhyung Kim <namhyung@kernel.org> Fixes: 1e10486ffee0a ("ftrace: Add 'function-fork' trace option") Fixes: c37775d57830a ("tracing: Add infrastructure to allow set_event_pid to follow children" Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21tracing/hwlat: Honor the tracing_cpumaskKevin Hao
commit 96b4833b6827a62c295b149213c68b559514c929 upstream. In calculation of the cpu mask for the hwlat kernel thread, the wrong cpu mask is used instead of the tracing_cpumask, this causes the tracing/tracing_cpumask useless for hwlat tracer. Fixes it. Link: https://lkml.kernel.org/r/20200730082318.42584-2-haokexin@gmail.com Cc: Ingo Molnar <mingo@redhat.com> Cc: stable@vger.kernel.org Fixes: 0330f7aa8ee6 ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs") Signed-off-by: Kevin Hao <haokexin@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21kprobes: Fix NULL pointer dereference at kprobe_ftrace_handlerMuchun Song
commit 0cb2f1372baa60af8456388a574af6133edd7d80 upstream. We found a case of kernel panic on our server. The stack trace is as follows(omit some irrelevant information): BUG: kernel NULL pointer dereference, address: 0000000000000080 RIP: 0010:kprobe_ftrace_handler+0x5e/0xe0 RSP: 0018:ffffb512c6550998 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff8e9d16eea018 RCX: 0000000000000000 RDX: ffffffffbe1179c0 RSI: ffffffffc0535564 RDI: ffffffffc0534ec0 RBP: ffffffffc0534ec1 R08: ffff8e9d1bbb0f00 R09: 0000000000000004 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: ffff8e9d1f797060 R14: 000000000000bacc R15: ffff8e9ce13eca00 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000080 CR3: 00000008453d0005 CR4: 00000000003606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <IRQ> ftrace_ops_assist_func+0x56/0xe0 ftrace_call+0x5/0x34 tcpa_statistic_send+0x5/0x130 [ttcp_engine] The tcpa_statistic_send is the function being kprobed. After analysis, the root cause is that the fourth parameter regs of kprobe_ftrace_handler is NULL. Why regs is NULL? We use the crash tool to analyze the kdump. crash> dis tcpa_statistic_send -r <tcpa_statistic_send>: callq 0xffffffffbd8018c0 <ftrace_caller> The tcpa_statistic_send calls ftrace_caller instead of ftrace_regs_caller. So it is reasonable that the fourth parameter regs of kprobe_ftrace_handler is NULL. In theory, we should call the ftrace_regs_caller instead of the ftrace_caller. After in-depth analysis, we found a reproducible path. Writing a simple kernel module which starts a periodic timer. The timer's handler is named 'kprobe_test_timer_handler'. The module name is kprobe_test.ko. 1) insmod kprobe_test.ko 2) bpftrace -e 'kretprobe:kprobe_test_timer_handler {}' 3) echo 0 > /proc/sys/kernel/ftrace_enabled 4) rmmod kprobe_test 5) stop step 2) kprobe 6) insmod kprobe_test.ko 7) bpftrace -e 'kretprobe:kprobe_test_timer_handler {}' We mark the kprobe as GONE but not disarm the kprobe in the step 4). The step 5) also do not disarm the kprobe when unregister kprobe. So we do not remove the ip from the filter. In this case, when the module loads again in the step 6), we will replace the code to ftrace_caller via the ftrace_module_enable(). When we register kprobe again, we will not replace ftrace_caller to ftrace_regs_caller because the ftrace is disabled in the step 3). So the step 7) will trigger kernel panic. Fix this problem by disarming the kprobe when the module is going away. Link: https://lkml.kernel.org/r/20200728064536.24405-1-songmuchun@bytedance.com Cc: stable@vger.kernel.org Fixes: ae6aa16fdc16 ("kprobes: introduce ftrace based optimization") Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Muchun Song <songmuchun@bytedance.com> Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com> Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21ftrace: Setup correct FTRACE_FL_REGS flags for moduleChengming Zhou
commit 8a224ffb3f52b0027f6b7279854c71a31c48fc97 upstream. When module loaded and enabled, we will use __ftrace_replace_code for module if any ftrace_ops referenced it found. But we will get wrong ftrace_addr for module rec in ftrace_get_addr_new, because rec->flags has not been setup correctly. It can cause the callback function of a ftrace_ops has FTRACE_OPS_FL_SAVE_REGS to be called with pt_regs set to NULL. So setup correct FTRACE_FL_REGS flags for rec when we call referenced_filters to find ftrace_ops references it. Link: https://lkml.kernel.org/r/20200728180554.65203-1-zhouchengming@bytedance.com Cc: stable@vger.kernel.org Fixes: 8c4f3c3fa9681 ("ftrace: Check module functions being traced on reload") Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com> Signed-off-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21mm: fix kthread_use_mm() vs TLB invalidatePeter Zijlstra
commit 38cf307c1f2011d413750c5acb725456f47d9172 upstream. For SMP systems using IPI based TLB invalidation, looking at current->active_mm is entirely reasonable. This then presents the following race condition: CPU0 CPU1 flush_tlb_mm(mm) use_mm(mm) <send-IPI> tsk->active_mm = mm; <IPI> if (tsk->active_mm == mm) // flush TLBs </IPI> switch_mm(old_mm,mm,tsk); Where it is possible the IPI flushed the TLBs for @old_mm, not @mm, because the IPI lands before we actually switched. Avoid this by disabling IRQs across changing ->active_mm and switch_mm(). Of the (SMP) architectures that have IPI based TLB invalidate: Alpha - checks active_mm ARC - ASID specific IA64 - checks active_mm MIPS - ASID specific flush OpenRISC - shoots down world PARISC - shoots down world SH - ASID specific SPARC - ASID specific x86 - N/A xtensa - checks active_mm So at the very least Alpha, IA64 and Xtensa are suspect. On top of this, for scheduler consistency we need at least preemption disabled across changing tsk->mm and doing switch_mm(), which is currently provided by task_lock(), but that's not sufficient for PREEMPT_RT. [akpm@linux-foundation.org: add comment] Reported-by: Andy Lutomirski <luto@amacapital.net> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Kees Cook <keescook@chromium.org> Cc: Jann Horn <jannh@google.com> Cc: Will Deacon <will@kernel.org> Cc: Christoph Hellwig <hch@lst.de> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: <stable@vger.kernel.org> Link: http://lkml.kernel.org/r/20200721154106.GE10769@hirez.programming.kicks-ass.net Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21pidfd: Add missing sock updates for pidfd_getfd()Kees Cook
commit 4969f8a073977123504609d7310b42a588297aa4 upstream. The sock counting (sock_update_netprioidx() and sock_update_classid()) was missing from pidfd's implementation of received fd installation. Add a call to the new __receive_sock() helper. Cc: Christian Brauner <christian.brauner@ubuntu.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Sargun Dhillon <sargun@sargun.me> Cc: Jakub Kicinski <kuba@kernel.org> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: stable@vger.kernel.org Fixes: 8649c322f75c ("pid: Implement pidfd_getfd syscall") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21genirq/PM: Always unlock IRQ descriptor in rearm_wake_irq()Guenter Roeck
commit e27b1636e9337d1a1d174b191e53d0f86421a822 upstream. rearm_wake_irq() does not unlock the irq descriptor if the interrupt is not suspended or if wakeup is not enabled on it. Restucture the exit conditions so the unlock is always ensured. Fixes: 3a79bc63d9075 ("PCI: irq: Introduce rearm_wake_irq()") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200811180001.80203-1-linux@roeck-us.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21genirq: Unlock irq descriptor after errorsGuenter Roeck
commit f107cee94ba4d2c7357fde59a1d84346c73d4958 upstream. In irq_set_irqchip_state(), the irq descriptor is not unlocked after an error is encountered. While that should never happen in practice, a buggy driver may trigger it. This would result in a lockup, so fix it. Fixes: 1d0326f352bb ("genirq: Check irq_data_get_irq_chip() return value before use") Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200811180012.80269-1-linux@roeck-us.net Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-21genirq/affinity: Make affinity setting if activated opt-inThomas Gleixner
commit f0c7baca180046824e07fc5f1326e83a8fd150c7 upstream. John reported that on a RK3288 system the perf per CPU interrupts are all affine to CPU0 and provided the analysis: "It looks like what happens is that because the interrupts are not per-CPU in the hardware, armpmu_request_irq() calls irq_force_affinity() while the interrupt is deactivated and then request_irq() with IRQF_PERCPU | IRQF_NOBALANCING. Now when irq_startup() runs with IRQ_STARTUP_NORMAL, it calls irq_setup_affinity() which returns early because IRQF_PERCPU and IRQF_NOBALANCING are set, leaving the interrupt on its original CPU." This was broken by the recent commit which blocked interrupt affinity setting in hardware before activation of the interrupt. While this works in general, it does not work for this particular case. As contrary to the initial analysis not all interrupt chip drivers implement an activate callback, the safe cure is to make the deferred interrupt affinity setting at activation time opt-in. Implement the necessary core logic and make the two irqchip implementations for which this is required opt-in. In hindsight this would have been the right thing to do, but ... Fixes: baedb87d1b53 ("genirq/affinity: Handle affinity setting on inactive interrupts correctly") Reported-by: John Keeping <john@metanate.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Marc Zyngier <maz@kernel.org> Acked-by: Marc Zyngier <maz@kernel.org> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/87blk4tzgm.fsf@nanos.tec.linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-19task_work: only grab task signal lock when neededJens Axboe
commit ebf0d100df0731901c16632f78d78d35f4123bc4 upstream. If JOBCTL_TASK_WORK is already set on the targeted task, then we need not go through {lock,unlock}_task_sighand() to set it again and queue a signal wakeup. This is safe as we're checking it _after_ adding the new task_work with cmpxchg(). The ordering is as follows: task_work_add() get_signal() -------------------------------------------------------------- STORE(task->task_works, new_work); STORE(task->jobctl); mb(); mb(); LOAD(task->jobctl); LOAD(task->task_works); This speeds up TWA_SIGNAL handling quite a bit, which is important now that io_uring is relying on it for all task_work deliveries. Cc: Peter Zijlstra <peterz@infradead.org> Cc: Jann Horn <jannh@google.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-19tick/nohz: Narrow down noise while setting current task's tick dependencyFrederic Weisbecker
commit 3c8920e2dbd1a55f72dc14d656df9d0097cf5c72 upstream. Setting a tick dependency on any task, including the case where a task sets that dependency on itself, triggers an IPI to all CPUs. That is of course suboptimal but it had previously not been an issue because it was only used by POSIX CPU timers on nohz_full, which apparently never occurs in latency-sensitive workloads in production. (Or users of such systems are suffering in silence on the one hand or venting their ire on the wrong people on the other.) But RCU now sets a task tick dependency on the current task in order to fix stall issues that can occur during RCU callback processing. Thus, RCU callback processing triggers frequent system-wide IPIs from nohz_full CPUs. This is quite counter-productive, after all, avoiding IPIs is what nohz_full is supposed to be all about. This commit therefore optimizes tasks' self-setting of a task tick dependency by using tick_nohz_full_kick() to avoid the system-wide IPI. Instead, only the execution of the one task is disturbed, which is acceptable given that this disturbance is well down into the noise compared to the degree to which the RCU callback processing itself disturbs execution. Fixes: 6a949b7af82d (rcu: Force on tick when invoking lots of callbacks) Reported-by: Matt Fleming <matt@codeblueprint.co.uk> Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Cc: stable@kernel.org Cc: Paul E. McKenney <paulmck@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-08-19ftrace: Fix ftrace_trace_task return valueJosef Bacik
[ Upstream commit c58b6b0372de0d4cd0536d6585addd1b36b151ae ] I was attempting to use pid filtering with function_graph, but it wasn't allowing anything to make it through. Turns out ftrace_trace_task returns false if ftrace_ignore_pid is not-empty, which isn't correct anymore. We're now setting it to FTRACE_PID_IGNORE if we need to ignore that pid, otherwise it's set to the pid (which is weird considering the name) or to FTRACE_PID_TRACE. Fix the check to check for != FTRACE_PID_IGNORE. With this we can now use function_graph with pid filtering. Link: https://lkml.kernel.org/r/20200725005048.1790-1-josef@toxicpanda.com Fixes: 717e3f5ebc82 ("ftrace: Make function trace pid filtering a bit more exact") Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19bpf: Fix pos computation for bpf_iter seq_ops->start()Yonghong Song
[ Upstream commit 3f9969f2c040ba2ba635b6b5a7051f404bcc634d ] Currently, the pos pointer in bpf iterator map/task/task_file seq_ops->start() is always incremented. This is incorrect. It should be increased only if *pos is 0 (for SEQ_START_TOKEN) since these start() function actually returns the first real object. If *pos is not 0, it merely found the object based on the state in seq->private, and not really advancing the *pos. This patch fixed this issue by only incrementing *pos if it is 0. Note that the old *pos calculation, although not correct, does not affect correctness of bpf_iter as bpf_iter seq_file->read() does not support llseek. This patch also renamed "mid" in bpf_map iterator seq_file private data to "map_id" for better clarity. Fixes: 6086d29def80 ("bpf: Add bpf_map iterator") Fixes: eaaacd23910f ("bpf: Add task and task/file iterator targets") Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200722195156.4029817-1-yhs@fb.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19tracing: Move pipe reference to trace array instead of current_tracerSteven Rostedt (VMware)
[ Upstream commit 7ef282e05132d56b6f6b71e3873f317664bea78b ] If a process has the trace_pipe open on a trace_array, the current tracer for that trace array should not be changed. This was original enforced by a global lock, but when instances were introduced, it was moved to the current_trace. But this structure is shared by all instances, and a trace_pipe is for a single instance. There's no reason that a process that has trace_pipe open on one instance should prevent another instance from changing its current tracer. Move the reference counter to the trace_array instead. This is marked as "Fixes" but is more of a clean up than a true fix. Backport if you want, but its not critical. Fixes: cf6ab6d9143b1 ("tracing: Add ref count to tracer for when they are being read by pipe") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19seccomp: Fix ioctl number for SECCOMP_IOCTL_NOTIF_ID_VALIDKees Cook
[ Upstream commit 47e33c05f9f07cac3de833e531bcac9ae052c7ca ] When SECCOMP_IOCTL_NOTIF_ID_VALID was first introduced it had the wrong direction flag set. While this isn't a big deal as nothing currently enforces these bits in the kernel, it should be defined correctly. Fix the define and provide support for the old command until it is no longer needed for backward compatibility. Fixes: 6a21cc50f0c7 ("seccomp: add a return code to trap to userspace") Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19sched/uclamp: Fix initialization of struct uclamp_rqQais Yousef
[ Upstream commit d81ae8aac85ca2e307d273f6dc7863a721bf054e ] struct uclamp_rq was zeroed out entirely in assumption that in the first call to uclamp_rq_inc() they'd be initialized correctly in accordance to default settings. But when next patch introduces a static key to skip uclamp_rq_{inc,dec}() until userspace opts in to use uclamp, schedutil will fail to perform any frequency changes because the rq->uclamp[UCLAMP_MAX].value is zeroed at init and stays as such. Which means all rqs are capped to 0 by default. Fix it by making sure we do proper initialization at init without relying on uclamp_rq_inc() doing it later. Fixes: 69842cba9ace ("sched/uclamp: Add CPU's clamp buckets refcounting") Signed-off-by: Qais Yousef <qais.yousef@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Tested-by: Lukasz Luba <lukasz.luba@arm.com> Link: https://lkml.kernel.org/r/20200630112123.12076-2-qais.yousef@arm.com Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19rcu/tree: Repeat the monitor if any free channel is busyUladzislau Rezki (Sony)
[ Upstream commit 594aa5975b9b5cfe9edaec06170e43b8c0607377 ] It is possible that one of the channels cannot be detached because its free channel is busy and previously queued data has not been processed yet. On the other hand, another channel can be successfully detached causing the monitor work to stop. Prevent that by rescheduling the monitor work if there are any channels in the pending state after a detach attempt. Fixes: 34c881745549e ("rcu: Support kfree_bulk() interface in kfree_rcu()") Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19blktrace: fix debugfs use after freeLuis Chamberlain
[ Upstream commit bad8e64fb19d3a0de5e564d9a7271c31bd684369 ] On commit 6ac93117ab00 ("blktrace: use existing disk debugfs directory") merged on v4.12 Omar fixed the original blktrace code for request-based drivers (multiqueue). This however left in place a possible crash, if you happen to abuse blktrace while racing to remove / add a device. We used to use asynchronous removal of the request_queue, and with that the issue was easier to reproduce. Now that we have reverted to synchronous removal of the request_queue, the issue is still possible to reproduce, its however just a bit more difficult. We essentially run two instances of break-blktrace which add/remove a loop device, and setup a blktrace and just never tear the blktrace down. We do this twice in parallel. This is easily reproduced with the script run_0004.sh from break-blktrace [0]. We can end up with two types of panics each reflecting where we race, one a failed blktrace setup: [ 252.426751] debugfs: Directory 'loop0' with parent 'block' already present! [ 252.432265] BUG: kernel NULL pointer dereference, address: 00000000000000a0 [ 252.436592] #PF: supervisor write access in kernel mode [ 252.439822] #PF: error_code(0x0002) - not-present page [ 252.442967] PGD 0 P4D 0 [ 252.444656] Oops: 0002 [#1] SMP NOPTI [ 252.446972] CPU: 10 PID: 1153 Comm: break-blktrace Tainted: G E 5.7.0-rc2-next-20200420+ #164 [ 252.452673] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014 [ 252.456343] RIP: 0010:down_write+0x15/0x40 [ 252.458146] Code: eb ca e8 ae 22 8d ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 55 48 89 fd e8 52 db ff ff 31 c0 ba 01 00 00 00 <f0> 48 0f b1 55 00 75 0f 48 8b 04 25 c0 8b 01 00 48 89 45 08 5d [ 252.463638] RSP: 0018:ffffa626415abcc8 EFLAGS: 00010246 [ 252.464950] RAX: 0000000000000000 RBX: ffff958c25f0f5c0 RCX: ffffff8100000000 [ 252.466727] RDX: 0000000000000001 RSI: ffffff8100000000 RDI: 00000000000000a0 [ 252.468482] RBP: 00000000000000a0 R08: 0000000000000000 R09: 0000000000000001 [ 252.470014] R10: 0000000000000000 R11: ffff958d1f9227ff R12: 0000000000000000 [ 252.471473] R13: ffff958c25ea5380 R14: ffffffff8cce15f1 R15: 00000000000000a0 [ 252.473346] FS: 00007f2e69dee540(0000) GS:ffff958c2fc80000(0000) knlGS:0000000000000000 [ 252.475225] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 252.476267] CR2: 00000000000000a0 CR3: 0000000427d10004 CR4: 0000000000360ee0 [ 252.477526] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 252.478776] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 252.479866] Call Trace: [ 252.480322] simple_recursive_removal+0x4e/0x2e0 [ 252.481078] ? debugfs_remove+0x60/0x60 [ 252.481725] ? relay_destroy_buf+0x77/0xb0 [ 252.482662] debugfs_remove+0x40/0x60 [ 252.483518] blk_remove_buf_file_callback+0x5/0x10 [ 252.484328] relay_close_buf+0x2e/0x60 [ 252.484930] relay_open+0x1ce/0x2c0 [ 252.485520] do_blk_trace_setup+0x14f/0x2b0 [ 252.486187] __blk_trace_setup+0x54/0xb0 [ 252.486803] blk_trace_ioctl+0x90/0x140 [ 252.487423] ? do_sys_openat2+0x1ab/0x2d0 [ 252.488053] blkdev_ioctl+0x4d/0x260 [ 252.488636] block_ioctl+0x39/0x40 [ 252.489139] ksys_ioctl+0x87/0xc0 [ 252.489675] __x64_sys_ioctl+0x16/0x20 [ 252.490380] do_syscall_64+0x52/0x180 [ 252.491032] entry_SYSCALL_64_after_hwframe+0x44/0xa9 And the other on the device removal: [ 128.528940] debugfs: Directory 'loop0' with parent 'block' already present! [ 128.615325] BUG: kernel NULL pointer dereference, address: 00000000000000a0 [ 128.619537] #PF: supervisor write access in kernel mode [ 128.622700] #PF: error_code(0x0002) - not-present page [ 128.625842] PGD 0 P4D 0 [ 128.627585] Oops: 0002 [#1] SMP NOPTI [ 128.629871] CPU: 12 PID: 544 Comm: break-blktrace Tainted: G E 5.7.0-rc2-next-20200420+ #164 [ 128.635595] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1 04/01/2014 [ 128.640471] RIP: 0010:down_write+0x15/0x40 [ 128.643041] Code: eb ca e8 ae 22 8d ff cc cc cc cc cc cc cc cc cc cc cc cc cc cc 0f 1f 44 00 00 55 48 89 fd e8 52 db ff ff 31 c0 ba 01 00 00 00 <f0> 48 0f b1 55 00 75 0f 65 48 8b 04 25 c0 8b 01 00 48 89 45 08 5d [ 128.650180] RSP: 0018:ffffa9c3c05ebd78 EFLAGS: 00010246 [ 128.651820] RAX: 0000000000000000 RBX: ffff8ae9a6370240 RCX: ffffff8100000000 [ 128.653942] RDX: 0000000000000001 RSI: ffffff8100000000 RDI: 00000000000000a0 [ 128.655720] RBP: 00000000000000a0 R08: 0000000000000002 R09: ffff8ae9afd2d3d0 [ 128.657400] R10: 0000000000000056 R11: 0000000000000000 R12: 0000000000000000 [ 128.659099] R13: 0000000000000000 R14: 0000000000000003 R15: 00000000000000a0 [ 128.660500] FS: 00007febfd995540(0000) GS:ffff8ae9afd00000(0000) knlGS:0000000000000000 [ 128.662204] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 128.663426] CR2: 00000000000000a0 CR3: 0000000420042003 CR4: 0000000000360ee0 [ 128.664776] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 128.666022] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 128.667282] Call Trace: [ 128.667801] simple_recursive_removal+0x4e/0x2e0 [ 128.668663] ? debugfs_remove+0x60/0x60 [ 128.669368] debugfs_remove+0x40/0x60 [ 128.669985] blk_trace_free+0xd/0x50 [ 128.670593] __blk_trace_remove+0x27/0x40 [ 128.671274] blk_trace_shutdown+0x30/0x40 [ 128.671935] blk_release_queue+0x95/0xf0 [ 128.672589] kobject_put+0xa5/0x1b0 [ 128.673188] disk_release+0xa2/0xc0 [ 128.673786] device_release+0x28/0x80 [ 128.674376] kobject_put+0xa5/0x1b0 [ 128.674915] loop_remove+0x39/0x50 [loop] [ 128.675511] loop_control_ioctl+0x113/0x130 [loop] [ 128.676199] ksys_ioctl+0x87/0xc0 [ 128.676708] __x64_sys_ioctl+0x16/0x20 [ 128.677274] do_syscall_64+0x52/0x180 [ 128.677823] entry_SYSCALL_64_after_hwframe+0x44/0xa9 The common theme here is: debugfs: Directory 'loop0' with parent 'block' already present This crash happens because of how blktrace uses the debugfs directory where it places its files. Upon init we always create the same directory which would be needed by blktrace but we only do this for make_request drivers (multiqueue) block drivers. When you race a removal of these devices with a blktrace setup you end up in a situation where the make_request recursive debugfs removal will sweep away the blktrace files and then later blktrace will also try to remove individual dentries which are already NULL. The inverse is also possible and hence the two types of use after frees. We don't create the block debugfs directory on init for these types of block devices: * request-based block driver block devices * every possible partition * scsi-generic And so, this race should in theory only be possible with make_request drivers. We can fix the UAF by simply re-using the debugfs directory for make_request drivers (multiqueue) and only creating the ephemeral directory for the other type of block devices. The new clarifications on relying on the q->blk_trace_mutex *and* also checking for q->blk_trace *prior* to processing a blktrace ensures the debugfs directories are only created if no possible directory name clashes are possible. This goes tested with: o nvme partitions o ISCSI with tgt, and blktracing against scsi-generic with: o block o tape o cdrom o media changer o blktests This patch is part of the work which disputes the severity of CVE-2019-19770 which shows this issue is not a core debugfs issue, but a misuse of debugfs within blktace. Fixes: 6ac93117ab00 ("blktrace: use existing disk debugfs directory") Reported-by: syzbot+603294af2d01acfdd6da@syzkaller.appspotmail.com Signed-off-by: Luis Chamberlain <mcgrof@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Omar Sandoval <osandov@fb.com> Cc: Hannes Reinecke <hare@suse.com> Cc: Nicolai Stange <nstange@suse.de> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: "Martin K. Petersen" <martin.petersen@oracle.com> Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> Cc: yu kuai <yukuai3@huawei.com> Signed-off-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19sched: correct SD_flags returned by tl->sd_flags()Peng Liu
[ Upstream commit 9b1b234bb86bcdcdb142e900d39b599185465dbb ] During sched domain init, we check whether non-topological SD_flags are returned by tl->sd_flags(), if found, fire a waning and correct the violation, but the code failed to correct the violation. Correct this. Fixes: 143e1e28cb40 ("sched: Rework sched_domain topology definition") Signed-off-by: Peng Liu <iwtbavbm@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Link: https://lkml.kernel.org/r/20200609150936.GA13060@iZj6chx1xj0e0buvshuecpZ Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-19sched/fair: Fix NOHZ next idle balanceVincent Guittot
[ Upstream commit 3ea2f097b17e13a8280f1f9386c331b326a3dbef ] With commit: 'b7031a02ec75 ("sched/fair: Add NOHZ_STATS_KICK")' rebalance_domains of the local cfs_rq happens before others idle cpus have updated nohz.next_balance and its value is overwritten. Move the update of nohz.next_balance for other idles cpus before balancing and updating the next_balance of local cfs_rq. Also, the nohz.next_balance is now updated only if all idle cpus got a chance to rebalance their domains and the idle balance has not been aborted because of new activities on the CPU. In case of need_resched, the idle load balance will be kick the next jiffie in order to address remaining ilb. Fixes: b7031a02ec75 ("sched/fair: Add NOHZ_STATS_KICK") Reported-by: Peng Liu <iwtbavbm@gmail.com> Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Mel Gorman <mgorman@suse.de> Link: https://lkml.kernel.org/r/20200609123748.18636-1-vincent.guittot@linaro.org Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-08-01Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Encap offset calculation is incorrect in esp6, from Sabrina Dubroca. 2) Better parameter validation in pfkey_dump(), from Mark Salyzyn. 3) Fix several clang issues on powerpc in selftests, from Tanner Love. 4) cmsghdr_from_user_compat_to_kern() uses the wrong length, from Al Viro. 5) Out of bounds access in mlx5e driver, from Raed Salem. 6) Fix transfer buffer memleak in lan78xx, from Johan Havold. 7) RCU fixups in rhashtable, from Herbert Xu. 8) Fix ipv6 nexthop refcnt leak, from Xiyu Yang. 9) vxlan FDB dump must be done under RCU, from Ido Schimmel. 10) Fix use after free in mlxsw, from Ido Schimmel. 11) Fix map leak in HASH_OF_MAPS bpf code, from Andrii Nakryiko. 12) Fix bug in mac80211 Tx ack status reporting, from Vasanthakumar Thiagarajan. 13) Fix memory leaks in IPV6_ADDRFORM code, from Cong Wang. 14) Fix bpf program reference count leaks in mlx5 during mlx5e_alloc_rq(), from Xin Xiong. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (86 commits) vxlan: fix memleak of fdb rds: Prevent kernel-infoleak in rds_notify_queue_get() net/sched: The error lable position is corrected in ct_init_module net/mlx5e: fix bpf_prog reference count leaks in mlx5e_alloc_rq net/mlx5e: E-Switch, Specify flow_source for rule with no in_port net/mlx5e: E-Switch, Add misc bit when misc fields changed for mirroring net/mlx5e: CT: Support restore ipv6 tunnel net: gemini: Fix missing clk_disable_unprepare() in error path of gemini_ethernet_port_probe() ionic: unlock queue mutex in error path atm: fix atm_dev refcnt leaks in atmtcp_remove_persistent net: ethernet: mtk_eth_soc: fix MTU warnings net: nixge: fix potential memory leak in nixge_probe() devlink: ignore -EOPNOTSUPP errors on dumpit rxrpc: Fix race between recvmsg and sendmsg on immediate call failure MAINTAINERS: Replace Thor Thayer as Altera Triple Speed Ethernet maintainer selftests/bpf: fix netdevsim trap_flow_action_cookie read ipv6: fix memory leaks on IPV6_ADDRFORM path net/bpfilter: Initialize pos in __bpfilter_process_sockopt igb: reinit_locked() should be called with rtnl_lock e1000e: continue to init PHY even when failed to disable ULP ...
2020-08-01Merge tag 'for-linus-2020-08-01' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux Pull thread fix from Christian Brauner: "A simple spelling fix for dequeue_synchronous_signal()" * tag 'for-linus-2020-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: signal: fix typo in dequeue_synchronous_signal()
2020-07-31Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpfDavid S. Miller
Daniel Borkmann says: ==================== pull-request: bpf 2020-07-31 The following pull-request contains BPF updates for your *net* tree. We've added 5 non-merge commits during the last 21 day(s) which contain a total of 5 files changed, 126 insertions(+), 18 deletions(-). The main changes are: 1) Fix a map element leak in HASH_OF_MAPS map type, from Andrii Nakryiko. 2) Fix a NULL pointer dereference in __btf_resolve_helper_id() when no btf_vmlinux is available, from Peilin Ye. 3) Init pos variable in __bpfilter_process_sockopt(), from Christoph Hellwig. 4) Fix a cgroup sockopt verifier test by specifying expected attach type, from Jean-Philippe Brucker. Note that when net gets merged into net-next later on, there is a small merge conflict in kernel/bpf/btf.c between commit 5b801dfb7feb ("bpf: Fix NULL pointer dereference in __btf_resolve_helper_id()") from the bpf tree and commit 138b9a0511c7 ("bpf: Remove btf_id helpers resolving") from the net-next tree. Resolve as follows: remove the old hunk with the __btf_resolve_helper_id() function. Change the btf_resolve_helper_id() so it actually tests for a NULL btf_vmlinux and bails out: int btf_resolve_helper_id(struct bpf_verifier_log *log, const struct bpf_func_proto *fn, int arg) { int id; if (fn->arg_type[arg] != ARG_PTR_TO_BTF_ID || !btf_vmlinux) return -EINVAL; id = fn->btf_id[arg]; if (!id || id > btf_vmlinux->nr_types) return -EINVAL; return id; } Let me know if you run into any others issues (CC'ing Jiri Olsa so he's in the loop with regards to merge conflict resolution). ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2020-07-30bpf: Fix map leak in HASH_OF_MAPS mapAndrii Nakryiko
Fix HASH_OF_MAPS bug of not putting inner map pointer on bpf_map_elem_update() operation. This is due to per-cpu extra_elems optimization, which bypassed free_htab_elem() logic doing proper clean ups. Make sure that inner map is put properly in optimized case as well. Fixes: 8c290e60fa2a ("bpf: fix hashmap extra_elems logic") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Song Liu <songliubraving@fb.com> Link: https://lore.kernel.org/bpf/20200729040913.2815687-1-andriin@fb.com
2020-07-29Merge tag 'audit-pr-20200729' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit Pull audit fixes from Paul Moore: "One small audit fix that you can hopefully merge before v5.8 is released. Unfortunately it is a revert of a patch that went in during the v5.7 window and we just recently started to see some bug reports relating to that commit. We are working on a proper fix, but I'm not yet clear on when that will be ready and we need to fix the v5.7 kernels anyway, so in the interest of time a revert seemed like the best solution right now" * tag 'audit-pr-20200729' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit: revert: 1320a4052ea1 ("audit: trigger accompanying records when no rules present")
2020-07-29random32: update the net random state on interrupt and activityWilly Tarreau
This modifies the first 32 bits out of the 128 bits of a random CPU's net_rand_state on interrupt or CPU activity to complicate remote observations that could lead to guessing the network RNG's internal state. Note that depending on some network devices' interrupt rate moderation or binding, this re-seeding might happen on every packet or even almost never. In addition, with NOHZ some CPUs might not even get timer interrupts, leaving their local state rarely updated, while they are running networked processes making use of the random state. For this reason, we also perform this update in update_process_times() in order to at least update the state when there is user or system activity, since it's the only case we care about. Reported-by: Amit Klein <aksecurity@gmail.com> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Eric Dumazet <edumazet@google.com> Cc: "Jason A. Donenfeld" <Jason@zx2c4.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Kees Cook <keescook@chromium.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: <stable@vger.kernel.org> Signed-off-by: Willy Tarreau <w@1wt.eu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-07-29revert: 1320a4052ea1 ("audit: trigger accompanying records when no rules ↵Paul Moore
present") Unfortunately the commit listed in the subject line above failed to ensure that the task's audit_context was properly initialized/set before enabling the "accompanying records". Depending on the situation, the resulting audit_context could have invalid values in some of it's fields which could cause a kernel panic/oops when the task/syscall exists and the audit records are generated. We will revisit the original patch, with the necessary fixes, in a future kernel but right now we just want to fix the kernel panic with the least amount of added risk. Cc: stable@vger.kernel.org Fixes: 1320a4052ea1 ("audit: trigger accompanying records when no rules present") Reported-by: j2468h@googlemail.com Signed-off-by: Paul Moore <paul@paul-moore.com>
2020-07-26signal: fix typo in dequeue_synchronous_signal()Pavel Machek
s/postive/positive/ Signed-off-by: Pavel Machek (CIP) <pavel@denx.de> Link: https://lore.kernel.org/r/20200724090531.GA14409@amd [christian.brauner@ubuntu.com: tweak commit message] Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-07-25Merge tag 'perf-urgent-2020-07-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master Pull uprobe fix from Ingo Molnar: "Fix an interaction/regression between uprobes based shared library tracing & GDB" * tag 'perf-urgent-2020-07-25' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: uprobes: Change handle_swbp() to send SIGTRAP with si_code=SI_KERNEL, to fix GDB regression
2020-07-24uprobes: Change handle_swbp() to send SIGTRAP with si_code=SI_KERNEL, to fix ↵Oleg Nesterov
GDB regression If a tracee is uprobed and it hits int3 inserted by debugger, handle_swbp() does send_sig(SIGTRAP, current, 0) which means si_code == SI_USER. This used to work when this code was written, but then GDB started to validate si_code and now it simply can't use breakpoints if the tracee has an active uprobe: # cat test.c void unused_func(void) { } int main(void) { return 0; } # gcc -g test.c -o test # perf probe -x ./test -a unused_func # perf record -e probe_test:unused_func gdb ./test -ex run GNU gdb (GDB) 10.0.50.20200714-git ... Program received signal SIGTRAP, Trace/breakpoint trap. 0x00007ffff7ddf909 in dl_main () from /lib64/ld-linux-x86-64.so.2 (gdb) The tracee hits the internal breakpoint inserted by GDB to monitor shared library events but GDB misinterprets this SIGTRAP and reports a signal. Change handle_swbp() to use force_sig(SIGTRAP), this matches do_int3_user() and fixes the problem. This is the minimal fix for -stable, arch/x86/kernel/uprobes.c is equally wrong; it should use send_sigtrap(TRAP_TRACE) instead of send_sig(SIGTRAP), but this doesn't confuse GDB and needs another x86-specific patch. Reported-by: Aaron Merey <amerey@redhat.com> Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200723154420.GA32043@redhat.com
2020-07-24sched: Warn if garbage is passed to default_wake_function()Chris Wilson
Since the default_wake_function() passes its flags onto try_to_wake_up(), warn if those flags collide with internal values. Given that the supplied flags are garbage, no repair can be done but at least alert the user to the damage they are causing. In the belief that these errors should be picked up during testing, the warning is only compiled in under CONFIG_SCHED_DEBUG. Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk> Signed-off-by: Ingo Molnar <mingo@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: https://lore.kernel.org/r/20200723201042.18861-1-chris@chris-wilson.co.uk
2020-07-22sched: Fix race against ptrace_freeze_trace()Peter Zijlstra
There is apparently one site that violates the rule that only current and ttwu() will modify task->state, namely ptrace_{,un}freeze_traced() will change task->state for a remote task. Oleg explains: "TASK_TRACED/TASK_STOPPED was always protected by siglock. In particular, ttwu(__TASK_TRACED) must be always called with siglock held. That is why ptrace_freeze_traced() assumes it can safely do s/TASK_TRACED/__TASK_TRACED/ under spin_lock(siglock)." This breaks the ordering scheme introduced by commit: dbfb089d360b ("sched: Fix loadavg accounting race") Specifically, the reload not matching no longer implies we don't have to block. Simply things by noting that what we need is a LOAD->STORE ordering and this can be provided by a control dependency. So replace: prev_state = prev->state; raw_spin_lock(&rq->lock); smp_mb__after_spinlock(); /* SMP-MB */ if (... && prev_state && prev_state == prev->state) deactivate_task(); with: prev_state = prev->state; if (... && prev_state) /* CTRL-DEP */ deactivate_task(); Since that already implies the 'prev->state' load must be complete before allowing the 'prev->on_rq = 0' store to become visible. Fixes: dbfb089d360b ("sched: Fix loadavg accounting race") Reported-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Oleg Nesterov <oleg@redhat.com> Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com> Tested-by: Christian Brauner <christian.brauner@ubuntu.com>
2020-07-19Merge tag 'timers-urgent-2020-07-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master Pull timer fixes from Thomas Gleixner: "Two fixes for the timer wheel: - A timer which is already expired at enqueue time can set the base->next_expiry value backwards. As a consequence base->clk can be set back as well. This can lead to timers expiring early. Add a sanity check to prevent this. - When a timer is queued with an expiry time beyond the wheel capacity then it should be queued in the bucket of the last wheel level which is expiring last. The code adjusted the expiry time to the maximum wheel capacity, which is only correct when the wheel clock is 0. Aside of that the check whether the delta is larger than wheel capacity does not check the delta, it checks the expiry value itself. As a result timers can expire at random. Fix this by checking the right variable and adjust expiry time so it becomes base->clock plus capacity which places it into the outmost bucket in the last wheel level" * tag 'timers-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: timer: Fix wheel index calculation on last level timer: Prevent base->clk from moving backward
2020-07-19Merge tag 'sched-urgent-2020-07-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master Pull scheduler fixes from Thomas Gleixner: "A set of scheduler fixes: - Plug a load average accounting race which was introduced with a recent optimization casing load average to show bogus numbers. - Fix the rseq CPU id initialization for new tasks. sched_fork() does not update the rseq CPU id so the id is the stale id of the parent task, which can cause user space data corruption. - Handle a 0 return value of task_h_load() correctly in the load balancer, which does not decrease imbalance and therefore pulls until the maximum number of loops is reached, which might be all tasks just created by a fork bomb" * tag 'sched-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched/fair: handle case of task_h_load() returning 0 sched: Fix unreliable rseq cpu_id for new tasks sched: Fix loadavg accounting race
2020-07-19Merge tag 'irq-urgent-2020-07-19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master Pull irq fixes from Thomas Gleixner: "Two fixes for the interrupt subsystem: - Make the handling of the firmware node consistent and do not free the node after the domain has been created successfully. The core code stores a pointer to it which can lead to a use after free or double free. This used to "work" because the pointer was not stored when the initial code was written, but at some point later it was required to store it. Of course nobody noticed that the existing users break that way. - Handle affinity setting on inactive interrupts correctly when hierarchical irq domains are enabled. When interrupts are inactive with the modern hierarchical irqdomain design, the interrupt chips are not necessarily in a state where affinity changes can be handled. The legacy irq chip design allowed this because interrupts are immediately fully initialized at allocation time. X86 has a hacky workaround for this, but other implementations do not. This cased malfunction on GIC-V3. Instead of playing whack a mole to find all affected drivers, change the core code to store the requested affinity setting and then establish it when the interrupt is allocated, which makes the X86 hack go away" * tag 'irq-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq/affinity: Handle affinity setting on inactive interrupts correctly irqdomain/treewide: Keep firmware node unconditionally allocated
2020-07-17genirq/affinity: Handle affinity setting on inactive interrupts correctlyThomas Gleixner
Setting interrupt affinity on inactive interrupts is inconsistent when hierarchical irq domains are enabled. The core code should just store the affinity and not call into the irq chip driver for inactive interrupts because the chip drivers may not be in a state to handle such requests. X86 has a hacky workaround for that but all other irq chips have not which causes problems e.g. on GIC V3 ITS. Instead of adding more ugly hacks all over the place, solve the problem in the core code. If the affinity is set on an inactive interrupt then: - Store it in the irq descriptors affinity mask - Update the effective affinity to reflect that so user space has a consistent view - Don't call into the irq chip driver This is the core equivalent of the X86 workaround and works correctly because the affinity setting is established in the irq chip when the interrupt is activated later on. Note, that this is only effective when hierarchical irq domains are enabled by the architecture. Doing it unconditionally would break legacy irq chip implementations. For hierarchial irq domains this works correctly as none of the drivers can have a dependency on affinity setting in inactive state by design. Remove the X86 workaround as it is not longer required. Fixes: 02edee152d6e ("x86/apic/vector: Ignore set_affinity call for inactive interrupts") Reported-by: Ali Saidi <alisaidi@amazon.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Ali Saidi <alisaidi@amazon.com> Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20200529015501.15771-1-alisaidi@amazon.com Link: https://lkml.kernel.org/r/877dv2rv25.fsf@nanos.tec.linutronix.de
2020-07-17timer: Fix wheel index calculation on last levelFrederic Weisbecker
When an expiration delta falls into the last level of the wheel, that delta has be compared against the maximum possible delay and reduced to fit in if necessary. However instead of comparing the delta against the maximum, the code compares the actual expiry against the maximum. Then instead of fixing the delta to fit in, it sets the maximum delta as the expiry value. This can result in various undesired outcomes, the worst possible one being a timer expiring 15 days ahead to fire immediately. Fixes: 500462a9de65 ("timers: Switch to a non-cascading wheel") Signed-off-by: Frederic Weisbecker <frederic@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: stable@vger.kernel.org Link: https://lkml.kernel.org/r/20200717140551.29076-2-frederic@kernel.org
2020-07-16sched/fair: handle case of task_h_load() returning 0Vincent Guittot
task_h_load() can return 0 in some situations like running stress-ng mmapfork, which forks thousands of threads, in a sched group on a 224 cores system. The load balance doesn't handle this correctly because env->imbalance never decreases and it will stop pulling tasks only after reaching loop_max, which can be equal to the number of running tasks of the cfs. Make sure that imbalance will be decreased by at least 1. misfit task is the other feature that doesn't handle correctly such situation although it's probably more difficult to face the problem because of the smaller number of CPUs and running tasks on heterogenous system. We can't simply ensure that task_h_load() returns at least one because it would imply to handle underflow in other places. Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: <stable@vger.kernel.org> # v4.4+ Link: https://lkml.kernel.org/r/20200710152426.16981-1-vincent.guittot@linaro.org
2020-07-15bpf: Fix NULL pointer dereference in __btf_resolve_helper_id()Peilin Ye
Prevent __btf_resolve_helper_id() from dereferencing `btf_vmlinux` as NULL. This patch fixes the following syzbot bug: https://syzkaller.appspot.com/bug?id=f823224ada908fa5c207902a5a62065e53ca0fcc Reported-by: syzbot+ee09bda7017345f1fbe6@syzkaller.appspotmail.com Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200714180904.277512-1-yepeilin.cs@gmail.com
2020-07-14dma-pool: do not allocate pool memory from CMANicolas Saenz Julienne
There is no guarantee to CMA's placement, so allocating a zone specific atomic pool from CMA might return memory from a completely different memory zone. So stop using it. Fixes: c84dc6e68a1d ("dma-pool: add additional coherent pools to map to gfp mask") Reported-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Tested-by: Jeremy Linton <jeremy.linton@arm.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14dma-pool: make sure atomic pool suits deviceNicolas Saenz Julienne
When allocating DMA memory from a pool, the core can only guess which atomic pool will fit a device's constraints. If it doesn't, get a safer atomic pool and try again. Fixes: c84dc6e68a1d ("dma-pool: add additional coherent pools to map to gfp mask") Reported-by: Jeremy Linton <jeremy.linton@arm.com> Suggested-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14dma-pool: introduce dma_guess_pool()Nicolas Saenz Julienne
dma-pool's dev_to_pool() creates the false impression that there is a way to grantee a mapping between a device's DMA constraints and an atomic pool. It tuns out it's just a guess, and the device might need to use an atomic pool containing memory from a 'safer' (or lower) memory zone. To help mitigate this, introduce dma_guess_pool() which can be fed a device's DMA constraints and atomic pools already known to be faulty, in order for it to provide an better guess on which pool to use. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14dma-pool: get rid of dma_in_atomic_pool()Nicolas Saenz Julienne
The function is only used once and can be simplified to a one-liner. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-14dma-direct: provide function to check physical memory area validityNicolas Saenz Julienne
dma_coherent_ok() checks if a physical memory area fits a device's DMA constraints. Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de>
2020-07-11Merge tag 'riscv-for-linus-5.8-rc5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux Pull RISC-V fixes from Palmer Dabbelt: "I have a few KGDB-related fixes. They're mostly fixes for build warnings, but there's also: - Support for the qSupported and qXfer packets, which are necessary to pass around GDB XML information which we need for the RISC-V GDB port to fully function. - Users can now select STRICT_KERNEL_RWX instead of forcing it on" * tag 'riscv-for-linus-5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: riscv: Avoid kgdb.h including gdb_xml.h to solve unused-const-variable warning kgdb: Move the extern declaration kgdb_has_hit_break() to generic kgdb.h riscv: Fix "no previous prototype" compile warning in kgdb.c file riscv: enable the Kconfig prompt of STRICT_KERNEL_RWX kgdb: enable arch to support XML packet.
2020-07-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netLinus Torvalds
Pull networking fixes from David Miller: 1) Restore previous behavior of CAP_SYS_ADMIN wrt loading networking BPF programs, from Maciej Żenczykowski. 2) Fix dropped broadcasts in mac80211 code, from Seevalamuthu Mariappan. 3) Slay memory leak in nl80211 bss color attribute parsing code, from Luca Coelho. 4) Get route from skb properly in ip_route_use_hint(), from Miaohe Lin. 5) Don't allow anything other than ARPHRD_ETHER in llc code, from Eric Dumazet. 6) xsk code dips too deeply into DMA mapping implementation internals. Add dma_need_sync and use it. From Christoph Hellwig 7) Enforce power-of-2 for BPF ringbuf sizes. From Andrii Nakryiko. 8) Check for disallowed attributes when loading flow dissector BPF programs. From Lorenz Bauer. 9) Correct packet injection to L3 tunnel devices via AF_PACKET, from Jason A. Donenfeld. 10) Don't advertise checksum offload on ipa devices that don't support it. From Alex Elder. 11) Resolve several issues in TCP MD5 signature support. Missing memory barriers, bogus options emitted when using syncookies, and failure to allow md5 key changes in established states. All from Eric Dumazet. 12) Fix interface leak in hsr code, from Taehee Yoo. 13) VF reset fixes in hns3 driver, from Huazhong Tan. 14) Make loopback work again with ipv6 anycast, from David Ahern. 15) Fix TX starvation under high load in fec driver, from Tobias Waldekranz. 16) MLD2 payload lengths not checked properly in bridge multicast code, from Linus Lüssing. 17) Packet scheduler code that wants to find the inner protocol currently only works for one level of VLAN encapsulation. Allow Q-in-Q situations to work properly here, from Toke Høiland-Jørgensen. 18) Fix route leak in l2tp, from Xin Long. 19) Resolve conflict between the sk->sk_user_data usage of bpf reuseport support and various protocols. From Martin KaFai Lau. 20) Fix socket cgroup v2 reference counting in some situations, from Cong Wang. 21) Cure memory leak in mlx5 connection tracking offload support, from Eli Britstein. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits) mlxsw: pci: Fix use-after-free in case of failed devlink reload mlxsw: spectrum_router: Remove inappropriate usage of WARN_ON() net: macb: fix call to pm_runtime in the suspend/resume functions net: macb: fix macb_suspend() by removing call to netif_carrier_off() net: macb: fix macb_get/set_wol() when moving to phylink net: macb: mark device wake capable when "magic-packet" property present net: macb: fix wakeup test in runtime suspend/resume routines bnxt_en: fix NULL dereference in case SR-IOV configuration fails libbpf: Fix libbpf hashmap on (I)LP32 architectures net/mlx5e: CT: Fix memory leak in cleanup net/mlx5e: Fix port buffers cell size value net/mlx5e: Fix 50G per lane indication net/mlx5e: Fix CPU mapping after function reload to avoid aRFS RX crash net/mlx5e: Fix VXLAN configuration restore after function reload net/mlx5e: Fix usage of rcu-protected pointer net/mxl5e: Verify that rpriv is not NULL net/mlx5: E-Switch, Fix vlan or qos setting in legacy mode net/mlx5: Fix eeprom support for SFP module cgroup: Fix sock_cgroup_data on big-endian. selftests: bpf: Fix detach from sockmap tests ...