user/sven/linux.git/kernel/trace/trace_kprobe.c, branch v5.18.3

kprobes: Use rethook for kretprobe if possible

2022-03-29T02:38:09Z

Use rethook for kretprobe function return hooking if the arch sets CONFIG_HAVE_RETHOOK=y. In this case, CONFIG_KRETPROBE_ON_RETHOOK is set to 'y' automatically, and the kretprobe internal data fields switches to use rethook. If not, it continues to use kretprobe specific function return hooks. Suggested-by: Peter Zijlstra Signed-off-by: Masami Hiramatsu Signed-off-by: Alexei Starovoitov Link: https://lore.kernel.org/bpf/164826162556.2455864.12255833167233452047.stgit@devnote2

tracing: Fix return value of __setup handlers

2022-03-04T18:46:13Z

__setup() handlers should generally return 1 to indicate that the boot options have been handled. Using invalid option values causes the entire kernel boot option string to be reported as Unknown and added to init's environment strings, polluting it. Unknown kernel command line parameters "BOOT_IMAGE=/boot/bzImage-517rc6 kprobe_event=p,syscall_any,$arg1 trace_options=quiet trace_clock=jiffies", will be passed to user space. Run /sbin/init as init process with arguments: /sbin/init with environment: HOME=/ TERM=linux BOOT_IMAGE=/boot/bzImage-517rc6 kprobe_event=p,syscall_any,$arg1 trace_options=quiet trace_clock=jiffies Return 1 from the __setup() handlers so that init's environment is not polluted with kernel boot options. Link: lore.kernel.org/r/64644a2f-4a20-bab3-1e15-3b2cdd0defe3@omprussia.ru Link: https://lkml.kernel.org/r/20220303031744.32356-1-rdunlap@infradead.org Cc: stable@vger.kernel.org Fixes: 7bcfaf54f591 ("tracing: Add trace_options kernel command line parameter") Fixes: e1e232ca6b8f ("tracing: Add trace_clock= kernel parameter") Fixes: 970988e19eb0 ("tracing/kprobe: Add kprobe_event= boot parameter") Signed-off-by: Randy Dunlap Reported-by: Igor Zhbanov Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (Google)

Merge tag 'trace-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace

2022-01-16T08:15:32Z

Pull tracing updates from Steven Rostedt: "New: - The Real Time Linux Analysis (RTLA) tool is added to the tools directory. - Can safely filter on user space pointers with: field.ustring ~ "match-string" - eprobes can now be filtered like any other event. - trace_marker(_raw) now uses stream_open() to allow multiple threads to safely write to it. Note, this could possibly break existing user space, but we will not know until we hear about it, and then can revert the change if need be. - New field in events to display when bottom halfs are disabled. - Sorting of the ftrace functions are now done at compile time instead of at bootup. Infrastructure changes to support future efforts: - Added __rel_loc type for trace events. Similar to __data_loc but the offset to the dynamic data is based off of the location of the descriptor and not the beginning of the event. Needed for user defined events. - Some simplification of event trigger code. - Make synthetic events process its callback better to not hinder other event callbacks that are registered. Needed for user defined events. And other small fixes and cleanups" * tag 'trace-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (50 commits) tracing: Add ustring operation to filtering string pointers rtla: Add rtla timerlat hist documentation rtla: Add rtla timerlat top documentation rtla: Add rtla timerlat documentation rtla: Add rtla osnoise hist documentation rtla: Add rtla osnoise top documentation rtla: Add rtla osnoise man page rtla: Add Documentation rtla/timerlat: Add timerlat hist mode rtla: Add timerlat tool and timelart top mode rtla/osnoise: Add the hist mode rtla/osnoise: Add osnoise top mode rtla: Add osnoise tool rtla: Helper functions for rtla rtla: Real-Time Linux Analysis tool tracing/osnoise: Properly unhook events if start_per_cpu_kthreads() fails tracing: Remove duplicate warnings when calling trace_create_file() tracing/kprobes: 'nmissed' not showed correctly for kretprobe tracing: Add test for user space strings when filtering on string pointers tracing: Have syscall trace events use trace_event_buffer_lock_reserve() ...

tracing/kprobes: 'nmissed' not showed correctly for kretprobe

2022-01-13T22:02:42Z

The 'nmissed' column of the 'kprobe_profile' file for kretprobe is not showed correctly, kretprobe can be skipped by two reasons, shortage of kretprobe_instance which is counted by tk->rp.nmissed, and kprobe itself is missed by some reason, so to show the sum. Link: https://lkml.kernel.org/r/20220107150242.5019-1-xyz.sun.ok@gmail.com Cc: stable@vger.kernel.org Fixes: 4a846b443b4e ("tracing/kprobes: Cleanup kprobe tracer code") Acked-by: Masami Hiramatsu Signed-off-by: Xiangyang Zhang Signed-off-by: Steven Rostedt

add missing bpf-cgroup.h includes

2021-12-16T22:57:09Z

We're about to break the cgroup-defs.h -> bpf-cgroup.h dependency, make sure those who actually need more than the definition of struct cgroup_bpf include bpf-cgroup.h explicitly. Signed-off-by: Jakub Kicinski Signed-off-by: Alexei Starovoitov Acked-by: Tejun Heo Link: https://lore.kernel.org/bpf/20211216025538.1649516-3-kuba@kernel.org

tracing: Iterate trace_[ku]probe objects directly

2021-12-11T14:34:32Z

As suggested by Linus [1] using list_for_each_entry to iterate directly trace_[ku]probe objects so we can skip another call to container_of in these loops. [1] https://lore.kernel.org/r/CAHk-=wjakjw6-rDzDDBsuMoDCqd+9ogifR_EE1F0K-jYek1CdA@mail.gmail.com Link: https://lkml.kernel.org/r/20211125202852.406405-1-jolsa@kernel.org Suggested-by: Linus Torvalds Signed-off-by: Jiri Olsa Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing/kprobes: Do not open code event reserve logic

2021-12-06T20:37:22Z

As kprobe events use trace_event_buffer_commit() to commit the event to the ftrace ring buffer, for consistency, it should use trace_event_buffer_reserve() to allocate it, as the two functions are related. Link: https://lkml.kernel.org/r/20211130024319.257430762@goodmis.org Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: Disable "other" permission bits in the tracefs files

2021-10-08T22:08:43Z

When building the files in the tracefs file system, do not by default set any permissions for OTH (other). This will make it easier for admins who want to define a group for accessing tracefs and not having to first disable all the permission bits for "other" in the file system. As tracing can leak sensitive information, it should never by default allowing all users access. An admin can still set the permission bits for others to have access, which may be useful for creating a honeypot and seeing who takes advantage of it and roots the machine. Link: https://lkml.kernel.org/r/20210818153038.864149276@goodmis.org Signed-off-by: Steven Rostedt (VMware)

kprobes: Use bool type for functions which returns boolean value

2021-10-01T01:24:06Z

Use the 'bool' type instead of 'int' for the functions which returns a boolean value, because this makes clear that those functions don't return any error code. Link: https://lkml.kernel.org/r/163163041649.489837.17311187321419747536.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: Add a probe that attaches to trace events

2021-08-20T18:18:40Z

A new dynamic event is introduced: event probe. The event is attached to an existing tracepoint and uses its fields as arguments. The user can specify custom format string of the new event, select what tracepoint arguments will be printed and how to print them. An event probe is created by writing configuration string in 'dynamic_events' ftrace file: e[:[SNAME/]ENAME] SYSTEM/EVENT [FETCHARGS] - Set an event probe -:SNAME/ENAME - Delete an event probe Where: SNAME - System name, if omitted 'eprobes' is used. ENAME - Name of the new event in SNAME, if omitted the SYSTEM_EVENT is used. SYSTEM - Name of the system, where the tracepoint is defined, mandatory. EVENT - Name of the tracepoint event in SYSTEM, mandatory. FETCHARGS - Arguments: =$[:TYPE] - Fetch given filed of the tracepoint and print it as given TYPE with given name. Supported types are: (u8/u16/u32/u64/s8/s16/s32/s64), basic type (x8/x16/x32/x64), hexadecimal types "string", "ustring" and bitfield. Example, attach an event probe on openat system call and print name of the file that will be opened: echo "e:esys/eopen syscalls/sys_enter_openat file=\$filename:string" >> dynamic_events A new dynamic event is created in events/esys/eopen/ directory. It can be deleted with: echo "-:esys/eopen" >> dynamic_events Filters, triggers and histograms can be attached to the new event, it can be matched in synthetic events. There is one limitation - an event probe can not be attached to kprobe, uprobe or another event probe. Link: https://lkml.kernel.org/r/20210812145805.2292326-1-tz.stoyanov@gmail.com Link: https://lkml.kernel.org/r/20210819152825.142428383@goodmis.org Acked-by: Masami Hiramatsu Co-developed-by: Steven Rostedt (VMware) Signed-off-by: Tzvetomir Stoyanov (VMware) Signed-off-by: Steven Rostedt (VMware)