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2023-07-11bpf: Clear the probe_addr for uprobeYafang Shao
To avoid returning uninitialized or random values when querying the file descriptor (fd) and accessing probe_addr, it is necessary to clear the variable prior to its use. Fixes: 41bdc4b40ed6 ("bpf: introduce bpf subcommand BPF_TASK_FD_QUERY") Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230709025630.3735-6-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-11bpf: Protect probed address based on kptr_restrict settingYafang Shao
The probed address can be accessed by userspace through querying the task file descriptor (fd). However, it is crucial to adhere to the kptr_restrict setting and refrain from exposing the address if it is not permitted. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/r/20230709025630.3735-5-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-11bpf: Support ->fill_link_info for kprobe_multiYafang Shao
With the addition of support for fill_link_info to the kprobe_multi link, users will gain the ability to inspect it conveniently using the `bpftool link show`. This enhancement provides valuable information to the user, including the count of probed functions and their respective addresses. It's important to note that if the kptr_restrict setting is not permitted, the probed address will not be exposed, ensuring security. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Acked-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/r/20230709025630.3735-2-laoar.shao@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-11bpf: cpumap: Fix memory leak in cpu_map_update_elemPu Lehui
Syzkaller reported a memory leak as follows: BUG: memory leak unreferenced object 0xff110001198ef748 (size 192): comm "syz-executor.3", pid 17672, jiffies 4298118891 (age 9.906s) hex dump (first 32 bytes): 00 00 00 00 4a 19 00 00 80 ad e3 e4 fe ff c0 00 ....J........... 00 b2 d3 0c 01 00 11 ff 28 f5 8e 19 01 00 11 ff ........(....... backtrace: [<ffffffffadd28087>] __cpu_map_entry_alloc+0xf7/0xb00 [<ffffffffadd28d8e>] cpu_map_update_elem+0x2fe/0x3d0 [<ffffffffadc6d0fd>] bpf_map_update_value.isra.0+0x2bd/0x520 [<ffffffffadc7349b>] map_update_elem+0x4cb/0x720 [<ffffffffadc7d983>] __se_sys_bpf+0x8c3/0xb90 [<ffffffffb029cc80>] do_syscall_64+0x30/0x40 [<ffffffffb0400099>] entry_SYSCALL_64_after_hwframe+0x61/0xc6 BUG: memory leak unreferenced object 0xff110001198ef528 (size 192): comm "syz-executor.3", pid 17672, jiffies 4298118891 (age 9.906s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<ffffffffadd281f0>] __cpu_map_entry_alloc+0x260/0xb00 [<ffffffffadd28d8e>] cpu_map_update_elem+0x2fe/0x3d0 [<ffffffffadc6d0fd>] bpf_map_update_value.isra.0+0x2bd/0x520 [<ffffffffadc7349b>] map_update_elem+0x4cb/0x720 [<ffffffffadc7d983>] __se_sys_bpf+0x8c3/0xb90 [<ffffffffb029cc80>] do_syscall_64+0x30/0x40 [<ffffffffb0400099>] entry_SYSCALL_64_after_hwframe+0x61/0xc6 BUG: memory leak unreferenced object 0xff1100010fd93d68 (size 8): comm "syz-executor.3", pid 17672, jiffies 4298118891 (age 9.906s) hex dump (first 8 bytes): 00 00 00 00 00 00 00 00 ........ backtrace: [<ffffffffade5db3e>] kvmalloc_node+0x11e/0x170 [<ffffffffadd28280>] __cpu_map_entry_alloc+0x2f0/0xb00 [<ffffffffadd28d8e>] cpu_map_update_elem+0x2fe/0x3d0 [<ffffffffadc6d0fd>] bpf_map_update_value.isra.0+0x2bd/0x520 [<ffffffffadc7349b>] map_update_elem+0x4cb/0x720 [<ffffffffadc7d983>] __se_sys_bpf+0x8c3/0xb90 [<ffffffffb029cc80>] do_syscall_64+0x30/0x40 [<ffffffffb0400099>] entry_SYSCALL_64_after_hwframe+0x61/0xc6 In the cpu_map_update_elem flow, when kthread_stop is called before calling the threadfn of rcpu->kthread, since the KTHREAD_SHOULD_STOP bit of kthread has been set by kthread_stop, the threadfn of rcpu->kthread will never be executed, and rcpu->refcnt will never be 0, which will lead to the allocated rcpu, rcpu->queue and rcpu->queue->queue cannot be released. Calling kthread_stop before executing kthread's threadfn will return -EINTR. We can complete the release of memory resources in this state. Fixes: 6710e1126934 ("bpf: introduce new bpf cpu map type BPF_MAP_TYPE_CPUMAP") Signed-off-by: Pu Lehui <pulehui@huawei.com> Acked-by: Jesper Dangaard Brouer <hawk@kernel.org> Acked-by: Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20230711115848.2701559-1-pulehui@huaweicloud.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-11cgroup: put cgroup_tryget_css() inside CONFIG_CGROUP_SCHEDMiaohe Lin
Put cgroup_tryget_css() inside CONFIG_CGROUP_SCHED to fix the warning of 'cgroup_tryget_css' defined but not used [-Wunused-function] when CONFIG_CGROUP_SCHED is disabled. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Kamalesh Babulal <kamalesh.babulal@oracle.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-11PM: QoS: Restore support for default value on frequency QoSChungkai Yang
Commit 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is non-negative") makes sure CPU freq is non-negative to avoid negative value converting to unsigned data type. However, when the value is PM_QOS_DEFAULT_VALUE, pm_qos_update_target specifically uses c->default_value which is set to FREQ_QOS_MIN/MAX_DEFAULT_VALUE when cpufreq_policy_alloc is executed, for this case handling. Adding check for PM_QOS_DEFAULT_VALUE to let default setting work will fix this problem. Fixes: 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is non-negative") Link: https://lore.kernel.org/lkml/20230626035144.19717-1-Chung-kai.Yang@mediatek.com/ Link: https://lore.kernel.org/lkml/20230627071727.16646-1-Chung-kai.Yang@mediatek.com/ Link: https://lore.kernel.org/lkml/CAJZ5v0gxNOWhC58PHeUhW_tgf6d1fGJVZ1x91zkDdht11yUv-A@mail.gmail.com/ Signed-off-by: Chungkai Yang <Chung-kai.Yang@mediatek.com> Cc: 6.0+ <stable@vger.kernel.org> # 6.0+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-07-11PM: hibernate: Fix writing maj:min to /sys/power/resumeAzat Khuzhin
resume_store() first calls lookup_bdev() and after tries to handle maj:min, but it does not reset the error before, hence if you will write maj:min you will get ENOENT: # echo 259:2 >| /sys/power/resume bash: echo: write error: No such file or directory This also should fix hiberation via systemd, since it uses this way. Fixes: 1e8c813b083c4 ("PM: hibernate: don't use early_lookup_bdev in resume_store") Signed-off-by: Azat Khuzhin <a3at.mail@gmail.com> Reviewed-by: Christoph Hellwig <hch@lst.de> [ rjw: Subject edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2023-07-10tracing/user_events: Fix struct arg size match checkBeau Belgrave
When users register an event the name of the event and it's argument are checked to ensure they match if the event already exists. Normally all arguments are in the form of "type name", except for when the type starts with "struct ". In those cases, the size of the struct is passed in addition to the name, IE: "struct my_struct a 20" for an argument that is of type "struct my_struct" with a field name of "a" and has the size of 20 bytes. The current code does not honor the above case properly when comparing a match. This causes the event register to fail even when the same string was used for events that contain a struct argument within them. The example above "struct my_struct a 20" generates a match string of "struct my_struct a" omitting the size field. Add the struct size of the existing field when generating a comparison string for a struct field to ensure proper match checking. Link: https://lkml.kernel.org/r/20230629235049.581-2-beaub@linux.microsoft.com Cc: stable@vger.kernel.org Fixes: e6f89a149872 ("tracing/user_events: Ensure user provided strings are safely formatted") Signed-off-by: Beau Belgrave <beaub@linux.microsoft.com> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-11fprobe: Ensure running fprobe_exit_handler() finished before calling ↵Masami Hiramatsu (Google)
rethook_free() Ensure running fprobe_exit_handler() has finished before calling rethook_free() in the unregister_fprobe() so that caller can free the fprobe right after unregister_fprobe(). unregister_fprobe() ensured that all running fprobe_entry/exit_handler() have finished by calling unregister_ftrace_function() which synchronizes RCU. But commit 5f81018753df ("fprobe: Release rethook after the ftrace_ops is unregistered") changed to call rethook_free() after unregister_ftrace_function(). So call rethook_stop() to make rethook disabled before unregister_ftrace_function() and ensure it again. Here is the possible code flow that can call the exit handler after unregister_fprobe(). ------ CPU1 CPU2 call unregister_fprobe(fp) ... __fprobe_handler() rethook_hook() on probed function unregister_ftrace_function() return from probed function rethook hooks find rh->handler == fprobe_exit_handler call fprobe_exit_handler() rethook_free(): set rh->handler = NULL; return from unreigster_fprobe; call fp->exit_handler() <- (*) ------ (*) At this point, the exit handler is called after returning from unregister_fprobe(). This fixes it as following; ------ CPU1 CPU2 call unregister_fprobe() ... rethook_stop(): set rh->handler = NULL; __fprobe_handler() rethook_hook() on probed function unregister_ftrace_function() return from probed function rethook hooks find rh->handler == NULL return from rethook rethook_free() return from unreigster_fprobe; ------ Link: https://lore.kernel.org/all/168873859949.156157.13039240432299335849.stgit@devnote2/ Fixes: 5f81018753df ("fprobe: Release rethook after the ftrace_ops is unregistered") Cc: stable@vger.kernel.org Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-10smp: Reduce NMI traffic from CSD waiters to CSD destinationImran Khan
On systems with hundreds of CPUs, if most of the CPUs detect a CSD hang, then all of these waiting CPUs send an NMI to the destination CPU in order to dump its backtrace. Given enough NMIs, the destination CPU will spent much of its time producing backtraces, thus further delaying that CPU's response to the original CSD IPI. In the worst case, by the time destination CPU is done producing all of these backtrace NMIs, the CSD wait timeout will have elapsed so that the waiters resend their backtrace NMIs again, further delaying forward progress. Therefore, to avoid these delays, issue the backtrace NMI only from the first waiter. The destination CPU's other waiters can make use of backtrace obtained from the first waiter's NMI. Signed-off-by: Imran Khan <imran.f.khan@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Yury Norov <yury.norov@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-07-10smp: Reduce logging due to dump_stack of CSD waitersImran Khan
If a waiter is waiting for CSD lock, its call stack will not change between first and subsequent hang detection for the same CSD lock. Therefore, do dump_stack only for first-time detection for a given waiter. This avoids excessive logging on systems with hundreds of CPUs where repetitive dump_stack from hundreds of CPUs would otherwise flood the console. Signed-off-by: Imran Khan <imran.f.khan@oracle.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Juergen Gross <jgross@suse.com> Cc: Valentin Schneider <vschneid@redhat.com> Cc: Yury Norov <yury.norov@gmail.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2023-07-10cgroup/cpuset: Allow suppression of sched domain rebuild in ↵Waiman Long
update_cpumasks_hier() A single partition setup and tear-down operation can lead to multiple rebuild_sched_domains_locked() calls which is a waste of effort. This can partly be mitigated by adding a flag to suppress the rebuild_sched_domains_locked() call in update_cpumasks_hier(). Since a Boolean flag has already been passed as the 3rd argument to update_cpumasks_hier(), we can extend that to a full flag word. The sched domain rebuild suppression is now enabled in update_sibling_cpumasks() as all it callers will do the sched domain rebuild after its return later on anyway. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cgroup/cpuset: Improve temporary cpumasks handlingWaiman Long
The limitation that update_parent_subparts_cpumask() can only use addmask & delmask in the given tmp cpumasks is fragile and may lead to unexpected error. Fix this problem by allocating/freeing a struct tmpmasks in update_cpumask() to avoid reusing the cpumasks in trial_cs. With this change, we can move the update_tasks_cpumask() for the parent and update_sibling_cpumasks() for the sibling to inside update_parent_subparts_cpumask(). Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cgroup/cpuset: Extract out CS_CPU_EXCLUSIVE & CS_SCHED_LOAD_BALANCE handlingWaiman Long
Extract out the setting of CS_CPU_EXCLUSIVE and CS_SCHED_LOAD_BALANCE flags as well as the rebuilding of scheduling domains into the new update_partition_exclusive() and update_partition_sd_lb() helper functions to simplify the logic. The update_partition_exclusive() helper is called mainly at the beginning of the caller, but it may be called at the end too. The update_partition_sd_lb() helper is called at the end of the caller. This patch should reduce the chance that cpuset partition will end up in an incorrect state. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cgroup/cpuset: Inherit parent's load balance state in v2Waiman Long
Since commit f28e22441f35 ("cgroup/cpuset: Add a new isolated cpus.partition type"), the CS_SCHED_LOAD_BALANCE bit of a v2 cpuset can be on or off. The child cpusets of a partition root must have the same setting as its parent or it may screw up the rebuilding of sched domains. Fix this problem by making sure the a child v2 cpuset will follows its parent cpuset load balance state unless the child cpuset is a new partition root itself. Fixes: f28e22441f35 ("cgroup/cpuset: Add a new isolated cpus.partition type") Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cgroup: fix obsolete comment above for_each_css()Miaohe Lin
cgroup_tree_mutex is removed since commit 8353da1f91f1 ("cgroup: remove cgroup_tree_mutex"), update corresponding comment. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10workqueue: add cmdline parameter `workqueue.unbound_cpus` to further ↵tiozhang
constrain wq_unbound_cpumask at boot time Motivation of doing this is to better improve boot times for devices when we want to prevent our workqueue works from running on some specific CPUs, e,g, some CPUs are busy with interrupts. Signed-off-by: tiozhang <tiozhang@didiglobal.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10workqueue: Warn attempt to flush system-wide workqueues.Tetsuo Handa
Based on commit c4f135d643823a86 ("workqueue: Wrap flush_workqueue() using a macro"), all in-tree users stopped flushing system-wide workqueues. Therefore, start emitting runtime message so that all out-of-tree users will understand that they need to update their code. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cpuset: Allow setscheduler regardless of manipulated taskMichal Koutný
When we migrate a task between two cgroups, one of the checks is a verification whether we can modify task's scheduler settings (cap_task_setscheduler()). An implicit migration occurs also when enabling a controller on the unified hierarchy (think of parent to child migration). The aforementioned check may be problematic if the caller of the migration (enabling a controller) has no permissions over migrated tasks. For instance, a user's cgroup that ends up running a process of a different user. Although cgroup permissions are configured favorably, the enablement fails due to the foreign process [1]. Change the behavior by relaxing the permissions check on the unified hierarchy when no effective change would happen. This is in accordance with unified hierarchy attachment behavior when permissions of the source to target cgroups are decisive whereas the migrated task is opaque (as opposed to more restrictive check in __cgroup1_procs_write()). Notice that foreign task's affinity may still be modified if the user can modify destination cgroup's cpuset attributes (update_tasks_cpumask() does no permissions check). The permissions check could thus be skipped on v2 even when affinity changes. Stay conservative in this patch though. [1] https://github.com/systemd/systemd/issues/18293#issuecomment-831205649 Signed-off-by: Michal Koutný <mkoutny@suse.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cgroup/cpuset: avoid unneeded cpuset_mutex re-lockMiaohe Lin
cpuset_mutex unlock and lock pair is only needed when transferring tasks out of empty cpuset. Avoid unneeded cpuset_mutex re-lock when !is_empty to save cpu cycles. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cgroup/cpuset: simplify the percpu kthreads check in update_tasks_cpumask()Miaohe Lin
kthread_is_per_cpu() can be called directly without checking whether PF_KTHREAD is set in task->flags. So remove PF_KTHREAD check to make code more concise. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10cgroup: minor cleanup for cgroup_extra_stat_show()Miaohe Lin
Make it under CONFIG_CGROUP_SCHED to rid of __maybe_unused annotation. And further fetch cgrp inside cgroup_extra_stat_show() directly to rid of __maybe_unused annotation of cgrp. No functional change intended. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-10kernel: params: Remove unnecessary ‘0’ values from errLi zeming
err is assigned first, so it does not need to initialize the assignment. Signed-off-by: Li zeming <zeming@nfschina.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-07-10module: Ignore RISC-V mapping symbols tooPalmer Dabbelt
RISC-V has an extended form of mapping symbols that we use to encode the ISA when it changes in the middle of an ELF. This trips up modpost as a build failure, I haven't yet verified it yet but I believe the kallsyms difference should result in stacks looking sane again. Reported-by: Randy Dunlap <rdunlap@infradead.org> Closes: https://lore.kernel.org/all/9d9e2902-5489-4bf0-d9cb-556c8e5d71c2@infradead.org/ Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-07-10cgroup: remove unneeded return value of cgroup_rm_cftypes_locked()Miaohe Lin
The return value of cgroup_rm_cftypes_locked() is always 0. So remove it to simplify the code. No functional change intended. Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2023-07-11kernel: kprobes: Remove unnecessary ‘0’ valuesLi zeming
it is assigned first, so it does not need to initialize the assignment. Link: https://lore.kernel.org/all/20230711185353.3218-1-zeming@nfschina.com/ Signed-off-by: Li zeming <zeming@nfschina.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-11kprobes: Remove unnecessary ‘NULL’ values from correct_ret_addrLi zeming
The 'correct_ret_addr' pointer is always set in the later code, no need to initialize it at definition time. Link: https://lore.kernel.org/all/20230704194359.3124-1-zeming@nfschina.com/ Signed-off-by: Li zeming <zeming@nfschina.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-11fprobe: add unlock to match a succeeded ftrace_test_recursion_trylockZe Gao
Unlock ftrace recursion lock when fprobe_kprobe_handler() is failed because of some running kprobe. Link: https://lore.kernel.org/all/20230703092336.268371-1-zegao@tencent.com/ Fixes: 3cc4e2c5fbae ("fprobe: make fprobe_kprobe_handler recursion free") Reported-by: Yafang <laoar.shao@gmail.com> Closes: https://lore.kernel.org/linux-trace-kernel/CALOAHbC6UpfFOOibdDiC7xFc5YFUgZnk3MZ=3Ny6we=AcrNbew@mail.gmail.com/ Signed-off-by: Ze Gao <zegao@tencent.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Acked-by: Yafang Shao <laoar.shao@gmail.com> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-11kernel/trace: Fix cleanup logic of enable_trace_eprobeTzvetomir Stoyanov (VMware)
The enable_trace_eprobe() function enables all event probes, attached to given trace probe. If an error occurs in enabling one of the event probes, all others should be roll backed. There is a bug in that roll back logic - instead of all event probes, only the failed one is disabled. Link: https://lore.kernel.org/all/20230703042853.1427493-1-tz.stoyanov@gmail.com/ Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Fixes: 7491e2c44278 ("tracing: Add a probe that attaches to trace events") Signed-off-by: Tzvetomir Stoyanov (VMware) <tz.stoyanov@gmail.com> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
2023-07-10perf/ring_buffer: Use local_try_cmpxchg in __perf_output_beginUros Bizjak
Use local_try_cmpxchg instead of local_cmpxchg (*ptr, old, new) == old in __perf_output_begin. x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails. There is no need to re-read the value in the loop. No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20230708090048.63046-2-ubizjak@gmail.com
2023-07-10perf/core: Use local64_try_cmpxchg in perf_swevent_set_periodUros Bizjak
Use local64_try_cmpxchg instead of local64_cmpxchg (*ptr, old, new) == old in perf_swevent_set_period. x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). Also, try_cmpxchg implicitly assigns old *ptr value to "old" when cmpxchg fails. There is no need to re-read the value in the loop. No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20230708081129.45915-1-ubizjak@gmail.com
2023-07-10sched/psi: use kernfs polling functions for PSI trigger pollingSuren Baghdasaryan
Destroying psi trigger in cgroup_file_release causes UAF issues when a cgroup is removed from under a polling process. This is happening because cgroup removal causes a call to cgroup_file_release while the actual file is still alive. Destroying the trigger at this point would also destroy its waitqueue head and if there is still a polling process on that file accessing the waitqueue, it will step on the freed pointer: do_select vfs_poll do_rmdir cgroup_rmdir kernfs_drain_open_files cgroup_file_release cgroup_pressure_release psi_trigger_destroy wake_up_pollfree(&t->event_wait) // vfs_poll is unblocked synchronize_rcu kfree(t) poll_freewait -> UAF access to the trigger's waitqueue head Patch [1] fixed this issue for epoll() case using wake_up_pollfree(), however the same issue exists for synchronous poll() case. The root cause of this issue is that the lifecycles of the psi trigger's waitqueue and of the file associated with the trigger are different. Fix this by using kernfs_generic_poll function when polling on cgroup-specific psi triggers. It internally uses kernfs_open_node->poll waitqueue head with its lifecycle tied to the file's lifecycle. This also renders the fix in [1] obsolete, so revert it. [1] commit c2dbe32d5db5 ("sched/psi: Fix use-after-free in ep_remove_wait_queue()") Fixes: 0e94682b73bf ("psi: introduce psi monitor") Closes: https://lore.kernel.org/all/20230613062306.101831-1-lujialin4@huawei.com/ Reported-by: Lu Jialin <lujialin4@huawei.com> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20230630005612.1014540-1-surenb@google.com
2023-07-10sched/fair: Use recent_used_cpu to test p->cpus_ptrMiaohe Lin
When checking whether a recently used CPU can be a potential idle candidate, recent_used_cpu should be used to test p->cpus_ptr as p->recent_used_cpu is not equal to recent_used_cpu and candidate decision is made based on recent_used_cpu here. Fixes: 89aafd67f28c ("sched/fair: Use prev instead of new target as recent_used_cpu") Signed-off-by: Miaohe Lin <linmiaohe@huawei.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Phil Auld <pauld@redhat.com> Acked-by: Mel Gorman <mgorman@suse.de> Link: https://lore.kernel.org/r/20230620080747.359122-1-linmiaohe@huawei.com
2023-07-09Merge tag 'dma-mapping-6.5-2023-07-09' of ↵Linus Torvalds
git://git.infradead.org/users/hch/dma-mapping Pull dma-mapping fixes from Christoph Hellwig: - swiotlb area sizing fixes (Petr Tesarik) * tag 'dma-mapping-6.5-2023-07-09' of git://git.infradead.org/users/hch/dma-mapping: swiotlb: reduce the number of areas to match actual memory pool size swiotlb: always set the number of areas before allocating the pool
2023-07-09Merge tag 'irq_urgent_for_v6.5_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull irq update from Borislav Petkov: - Optimize IRQ domain's name assignment * tag 'irq_urgent_for_v6.5_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: irqdomain: Use return value of strreplace()
2023-07-08fork: lock VMAs of the parent process when forkingSuren Baghdasaryan
When forking a child process, the parent write-protects anonymous pages and COW-shares them with the child being forked using copy_present_pte(). We must not take any concurrent page faults on the source vma's as they are being processed, as we expect both the vma and the pte's behind it to be stable. For example, the anon_vma_fork() expects the parents vma->anon_vma to not change during the vma copy. A concurrent page fault on a page newly marked read-only by the page copy might trigger wp_page_copy() and a anon_vma_prepare(vma) on the source vma, defeating the anon_vma_clone() that wasn't done because the parent vma originally didn't have an anon_vma, but we now might end up copying a pte entry for a page that has one. Before the per-vma lock based changes, the mmap_lock guaranteed exclusion with concurrent page faults. But now we need to do a vma_start_write() to make sure no concurrent faults happen on this vma while it is being processed. This fix can potentially regress some fork-heavy workloads. Kernel build time did not show noticeable regression on a 56-core machine while a stress test mapping 10000 VMAs and forking 5000 times in a tight loop shows ~5% regression. If such fork time regression is unacceptable, disabling CONFIG_PER_VMA_LOCK should restore its performance. Further optimizations are possible if this regression proves to be problematic. Suggested-by: David Hildenbrand <david@redhat.com> Reported-by: Jiri Slaby <jirislaby@kernel.org> Closes: https://lore.kernel.org/all/dbdef34c-3a07-5951-e1ae-e9c6e3cdf51b@kernel.org/ Reported-by: Holger Hoffstätte <holger@applied-asynchrony.com> Closes: https://lore.kernel.org/all/b198d649-f4bf-b971-31d0-e8433ec2a34c@applied-asynchrony.com/ Reported-by: Jacob Young <jacobly.alt@gmail.com> Closes: https://bugzilla.kernel.org/show_bug.cgi?id=217624 Fixes: 0bff0aaea03e ("x86/mm: try VMA lock-based page fault handling first") Cc: stable@vger.kernel.org Signed-off-by: Suren Baghdasaryan <surenb@google.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-07-06Merge tag 'trace-v6.5-2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix bad git merge of #endif in arm64 code A merge of the arm64 tree caused #endif to go into the wrong place - Fix crash on lseek of write access to tracefs/error_log Opening error_log as write only, and then doing an lseek() causes a kernel panic, because the lseek() handle expects a "seq_file" to exist (which is not done on write only opens). Use tracing_lseek() that tests for this instead of calling the default seq lseek handler. - Check for negative instead of -E2BIG for error on strscpy() returns Instead of testing for -E2BIG from strscpy(), to be more robust, check for less than zero, which will make sure it catches any error that strscpy() may someday return. * tag 'trace-v6.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: tracing/boot: Test strscpy() against less than zero for error arm64: ftrace: fix build error with CONFIG_FUNCTION_GRAPH_TRACER=n tracing: Fix null pointer dereference in tracing_err_log_open()
2023-07-06bpf: make preloaded map iterators to display map elements countAnton Protopopov
Add another column to the /sys/fs/bpf/maps.debug iterator to display cur_entries, the current number of entries in the map as is returned by the bpf_map_sum_elem_count kfunc. Also fix formatting. Example: # cat /sys/fs/bpf/maps.debug id name max_entries cur_entries 2 iterator.rodata 1 0 125 cilium_auth_map 524288 666 126 cilium_runtime_ 256 0 127 cilium_signals 32 0 128 cilium_node_map 16384 1344 129 cilium_events 32 0 ... Signed-off-by: Anton Protopopov <aspsk@isovalent.com> Link: https://lore.kernel.org/r/20230706133932.45883-5-aspsk@isovalent.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-06bpf: populate the per-cpu insertions/deletions counters for hashmapsAnton Protopopov
Initialize and utilize the per-cpu insertions/deletions counters for hash-based maps. Non-trivial changes only apply to the preallocated maps for which the {inc,dec}_elem_count functions are not called, as there's no need in counting elements to sustain proper map operations. To increase/decrease percpu counters for preallocated maps we add raw calls to the bpf_map_{inc,dec}_elem_count functions so that the impact is minimal. For dynamically allocated maps we add corresponding calls to the existing {inc,dec}_elem_count functions. Signed-off-by: Anton Protopopov <aspsk@isovalent.com> Link: https://lore.kernel.org/r/20230706133932.45883-4-aspsk@isovalent.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-06bpf: add a new kfunc to return current bpf_map elements countAnton Protopopov
A bpf_map_sum_elem_count kfunc was added to simplify getting the sum of the map per-cpu element counters. If a map doesn't implement the counter, then the function will always return 0. Signed-off-by: Anton Protopopov <aspsk@isovalent.com> Link: https://lore.kernel.org/r/20230706133932.45883-3-aspsk@isovalent.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-06Merge tag 'asm-generic-6.5' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic Pull asm-generic updates from Arnd Bergmann: "These are cleanups for architecture specific header files: - the comments in include/linux/syscalls.h have gone out of sync and are really pointless, so these get removed - The asm/bitsperlong.h header no longer needs to be architecture specific on modern compilers, so use a generic version for newer architectures that use new enough userspace compilers - A cleanup for virt_to_pfn/virt_to_bus to have proper type checking, forcing the use of pointers" * tag 'asm-generic-6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/arnd/asm-generic: syscalls: Remove file path comments from headers tools arch: Remove uapi bitsperlong.h of hexagon and microblaze asm-generic: Unify uapi bitsperlong.h for arm64, riscv and loongarch m68k/mm: Make pfn accessors static inlines arm64: memory: Make virt_to_pfn() a static inline ARM: mm: Make virt_to_pfn() a static inline asm-generic/page.h: Make pfn accessors static inlines xen/netback: Pass (void *) to virt_to_page() netfs: Pass a pointer to virt_to_page() cifs: Pass a pointer to virt_to_page() in cifsglob cifs: Pass a pointer to virt_to_page() riscv: mm: init: Pass a pointer to virt_to_page() ARC: init: Pass a pointer to virt_to_pfn() in init m68k: Pass a pointer to virt_to_pfn() virt_to_page() fs/proc/kcore.c: Pass a pointer to virt_addr_valid()
2023-07-05bpf: Fix max stack depth check for async callbacksKumar Kartikeya Dwivedi
The check_max_stack_depth pass happens after the verifier's symbolic execution, and attempts to walk the call graph of the BPF program, ensuring that the stack usage stays within bounds for all possible call chains. There are two cases to consider: bpf_pseudo_func and bpf_pseudo_call. In the former case, the callback pointer is loaded into a register, and is assumed that it is passed to some helper later which calls it (however there is no way to be sure), but the check remains conservative and accounts the stack usage anyway. For this particular case, asynchronous callbacks are skipped as they execute asynchronously when their corresponding event fires. The case of bpf_pseudo_call is simpler and we know that the call is definitely made, hence the stack depth of the subprog is accounted for. However, the current check still skips an asynchronous callback even if a bpf_pseudo_call was made for it. This is erroneous, as it will miss accounting for the stack usage of the asynchronous callback, which can be used to breach the maximum stack depth limit. Fix this by only skipping asynchronous callbacks when the instruction is not a pseudo call to the subprog. Fixes: 7ddc80a476c2 ("bpf: Teach stack depth check about async callbacks.") Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Link: https://lore.kernel.org/r/20230705144730.235802-2-memxor@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-07-05Merge tag 'net-6.5-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net Pull networking fixes from Jakub Kicinski: "Including fixes from bluetooth, bpf and wireguard. Current release - regressions: - nvme-tcp: fix comma-related oops after sendpage changes Current release - new code bugs: - ptp: make max_phase_adjustment sysfs device attribute invisible when not supported Previous releases - regressions: - sctp: fix potential deadlock on &net->sctp.addr_wq_lock - mptcp: - ensure subflow is unhashed before cleaning the backlog - do not rely on implicit state check in mptcp_listen() Previous releases - always broken: - net: fix net_dev_start_xmit trace event vs skb_transport_offset() - Bluetooth: - fix use-bdaddr-property quirk - L2CAP: fix multiple UaFs - ISO: use hci_sync for setting CIG parameters - hci_event: fix Set CIG Parameters error status handling - hci_event: fix parsing of CIS Established Event - MGMT: fix marking SCAN_RSP as not connectable - wireguard: queuing: use saner cpu selection wrapping - sched: act_ipt: various bug fixes for iptables <> TC interactions - sched: act_pedit: add size check for TCA_PEDIT_PARMS_EX - dsa: fixes for receiving PTP packets with 8021q and sja1105 tagging - eth: sfc: fix null-deref in devlink port without MAE access - eth: ibmvnic: do not reset dql stats on NON_FATAL err Misc: - xsk: honor SO_BINDTODEVICE on bind" * tag 'net-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (70 commits) nfp: clean mc addresses in application firmware when closing port selftests: mptcp: pm_nl_ctl: fix 32-bit support selftests: mptcp: depend on SYN_COOKIES selftests: mptcp: userspace_pm: report errors with 'remove' tests selftests: mptcp: userspace_pm: use correct server port selftests: mptcp: sockopt: return error if wrong mark selftests: mptcp: sockopt: use 'iptables-legacy' if available selftests: mptcp: connect: fail if nft supposed to work mptcp: do not rely on implicit state check in mptcp_listen() mptcp: ensure subflow is unhashed before cleaning the backlog s390/qeth: Fix vipa deletion octeontx-af: fix hardware timestamp configuration net: dsa: sja1105: always enable the send_meta options net: dsa: tag_sja1105: fix MAC DA patching from meta frames net: Replace strlcpy with strscpy pptp: Fix fib lookup calls. mlxsw: spectrum_router: Fix an IS_ERR() vs NULL check net/sched: act_pedit: Add size check for TCA_PEDIT_PARMS_EX xsk: Honor SO_BINDTODEVICE on bind ptp: Make max_phase_adjustment sysfs device attribute invisible when not supported ...
2023-07-05tracing/boot: Test strscpy() against less than zero for errorSteven Rostedt (Google)
Instead of checking for -E2BIG, it is better to just check for less than zero of strscpy() for error. Testing for -E2BIG is not very robust, and the calling code does not really care about the error code, just that there was an error. One of the updates to convert strlcpy() to strscpy() had a v2 version that changed the test from testing against -E2BIG to less than zero, but I took the v1 version that still tested for -E2BIG. Link: https://lore.kernel.org/linux-trace-kernel/20230615180420.400769-1-azeemshaikh38@gmail.com/ Link: https://lore.kernel.org/linux-trace-kernel/20230704100807.707d1605@rorschach.local.home Cc: Mark Rutland <mark.rutland@arm.com> Cc: Azeem Shaikh <azeemshaikh38@gmail.com> Cc: Kees Cook <keescook@chromium.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-05tracing: Fix null pointer dereference in tracing_err_log_open()Mateusz Stachyra
Fix an issue in function 'tracing_err_log_open'. The function doesn't call 'seq_open' if the file is opened only with write permissions, which results in 'file->private_data' being left as null. If we then use 'lseek' on that opened file, 'seq_lseek' dereferences 'file->private_data' in 'mutex_lock(&m->lock)', resulting in a kernel panic. Writing to this node requires root privileges, therefore this bug has very little security impact. Tracefs node: /sys/kernel/tracing/error_log Example Kernel panic: Unable to handle kernel NULL pointer dereference at virtual address 0000000000000038 Call trace: mutex_lock+0x30/0x110 seq_lseek+0x34/0xb8 __arm64_sys_lseek+0x6c/0xb8 invoke_syscall+0x58/0x13c el0_svc_common+0xc4/0x10c do_el0_svc+0x24/0x98 el0_svc+0x24/0x88 el0t_64_sync_handler+0x84/0xe4 el0t_64_sync+0x1b4/0x1b8 Code: d503201f aa0803e0 aa1f03e1 aa0103e9 (c8e97d02) ---[ end trace 561d1b49c12cf8a5 ]--- Kernel panic - not syncing: Oops: Fatal exception Link: https://lore.kernel.org/linux-trace-kernel/20230703155237eucms1p4dfb6a19caa14c79eb6c823d127b39024@eucms1p4 Link: https://lore.kernel.org/linux-trace-kernel/20230704102706eucms1p30d7ecdcc287f46ad67679fc8491b2e0f@eucms1p3 Cc: stable@vger.kernel.org Fixes: 8a062902be725 ("tracing: Add tracing error log") Signed-off-by: Mateusz Stachyra <m.stachyra@samsung.com> Suggested-by: Steven Rostedt <rostedt@goodmis.org> Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-07-05bpf: Remove unnecessary ring buffer size checkHou Tao
The theoretical maximum size of ring buffer is about 64GB, but now the size of ring buffer is specified by max_entries in bpf_attr and its maximum value is (4GB - 1), and it won't be possible for overflow. So just remove the unnecessary size check in ringbuf_map_alloc() but keep the comments for possible extension in future. Reported-by: Dan Carpenter <dan.carpenter@linaro.org> Signed-off-by: Hou Tao <houtao1@huawei.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Closes: https://lore.kernel.org/bpf/9c636a63-1f3d-442d-9223-96c2dccb9469@moroto.mountain Link: https://lore.kernel.org/bpf/20230704074014.216616-1-houtao@huaweicloud.com
2023-07-04module: fix init_module_from_file() error handlingLinus Torvalds
Vegard Nossum pointed out two different problems with the error handling in init_module_from_file(): (a) the idempotent loading code didn't clean up properly in some error cases, leaving the on-stack 'struct idempotent' element still in the hash table (b) failure to read the module file would nonsensically update the 'invalid_kread_bytes' stat counter with the error value The first error is quite nasty, in that it can then cause subsequent idempotent loads of that same file to access stale stack contents of the previous failure. The case may not happen in any normal situation (explaining all the "Tested-by's on the original change), and requires admin privileges, but syzkaller triggers random bad behavior as a result: BUG: soft lockup in sys_finit_module BUG: unable to handle kernel paging request in init_module_from_file general protection fault in init_module_from_file INFO: task hung in init_module_from_file KASAN: out-of-bounds Read in init_module_from_file KASAN: slab-out-of-bounds Read in init_module_from_file ... The second error is fairly benign and just leads to nonsensical stats (and has been around since the debug stats were added). Vegard also provided a patch for the idempotent loading issue, but I'd rather re-organize the code and make it more legible using another level of helper functions than add the usual "goto out" error handling. Link: https://lore.kernel.org/lkml/20230704100852.23452-1-vegard.nossum@oracle.com/ Fixes: 9b9879fc0327 ("modules: catch concurrent module loads, treat them as idempotent") Reported-by: Vegard Nossum <vegard.nossum@oracle.com> Reported-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com> Reported-by: syzbot+9c2bdc9d24e4a7abe741@syzkaller.appspotmail.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-07-03Merge tag 'kgdb-6.5-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux Pull kgdb updates from Daniel Thompson: "Fairly small changes this cycle: - An additional static inline function when kgdb is not enabled to reduce boilerplate in arch files - kdb will now handle input with linefeeds more like carriage return. This will make little difference for interactive use but can make it script to use expect-like interaction with kdb - A couple of warning fixes" * tag 'kgdb-6.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux: kdb: move kdb_send_sig() declaration to a better header file kdb: Handle LF in the command parser kdb: include kdb_private.h for function prototypes kgdb: Provide a stub kgdb_nmicallback() if !CONFIG_KGDB
2023-07-03bpf, btf: Warn but return no error for NULL btf from ↵SeongJae Park
__register_btf_kfunc_id_set() __register_btf_kfunc_id_set() assumes .BTF to be part of the module's .ko file if CONFIG_DEBUG_INFO_BTF is enabled. If that's not the case, the function prints an error message and return an error. As a result, such modules cannot be loaded. However, the section could be stripped out during a build process. It would be better to let the modules loaded, because their basic functionalities have no problem [0], though the BTF functionalities will not be supported. Make the function to lower the level of the message from error to warn, and return no error. [0] https://lore.kernel.org/bpf/20220219082037.ow2kbq5brktf4f2u@apollo.legion Fixes: c446fdacb10d ("bpf: fix register_btf_kfunc_id_set for !CONFIG_DEBUG_INFO_BTF") Reported-by: Alexander Egorenkov <Alexander.Egorenkov@ibm.com> Suggested-by: Kumar Kartikeya Dwivedi <memxor@gmail.com> Signed-off-by: SeongJae Park <sj@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Jiri Olsa <jolsa@kernel.org> Link: https://lore.kernel.org/bpf/87y228q66f.fsf@oc8242746057.ibm.com Link: https://lore.kernel.org/bpf/20220219082037.ow2kbq5brktf4f2u@apollo.legion Link: https://lore.kernel.org/bpf/20230701171447.56464-1-sj@kernel.org
2023-07-03kdb: move kdb_send_sig() declaration to a better header fileDaniel Thompson
kdb_send_sig() is defined in the signal code and called from kdb, but the declaration is part of the kdb internal code. Move the declaration to the shared header to avoid the warning: kernel/signal.c:4789:6: error: no previous prototype for 'kdb_send_sig' [-Werror=missing-prototypes] Reported-by: Arnd Bergmann <arnd@arndb.de> Closes: https://lore.kernel.org/lkml/20230517125423.930967-1-arnd@kernel.org/ Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org> Link: https://lore.kernel.org/r/20230630201206.2396930-1-daniel.thompson@linaro.org