android_kernel_motorola_sm6375/kernel/trace
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Steven Rostedt (VMware) c65755f595 tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing
commit 9913d5745bd720c4266805c8d29952a3702e4eca upstream.

All internal use cases for tracepoint_probe_register() is set to not ever
be called with the same function and data. If it is, it is considered a
bug, as that means the accounting of handling tracepoints is corrupted.
If the function and data for a tracepoint is already registered when
tracepoint_probe_register() is called, it will call WARN_ON_ONCE() and
return with EEXISTS.

The BPF system call can end up calling tracepoint_probe_register() with
the same data, which now means that this can trigger the warning because
of a user space process. As WARN_ON_ONCE() should not be called because
user space called a system call with bad data, there needs to be a way to
register a tracepoint without triggering a warning.

Enter tracepoint_probe_register_may_exist(), which can be called, but will
not cause a WARN_ON() if the probe already exists. It will still error out
with EEXIST, which will then be sent to the user space that performed the
BPF system call.

This keeps the previous testing for issues with other users of the
tracepoint code, while letting BPF call it with duplicated data and not
warn about it.

Link: https://lore.kernel.org/lkml/20210626135845.4080-1-penguin-kernel@I-love.SAKURA.ne.jp/
Link: https://syzkaller.appspot.com/bug?id=41f4318cf01762389f4d1c1c459da4f542fe5153

Cc: stable@vger.kernel.org
Fixes: c4f6699dfc ("bpf: introduce BPF_RAW_TRACEPOINT")
Reported-by: syzbot <syzbot+721aa903751db87aa244@syzkaller.appspotmail.com>
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Tested-by: syzbot+721aa903751db87aa244@syzkaller.appspotmail.com
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-07-14 16:53:08 +02:00
..
blktrace.c blktrace: ensure our debugfs dir exists 2020-09-03 11:26:42 +02:00
bpf_trace.c tracepoint: Add tracepoint_probe_register_may_exist() for BPF tracing 2021-07-14 16:53:08 +02:00
fgraph.c fgraph: Initialize tracing_graph_pause at task creation 2021-02-10 09:25:29 +01:00
ftrace.c ftrace: Do not blindly read the ip address in ftrace_bug() 2021-06-16 11:59:45 +02:00
ftrace_internal.h
Kconfig tracing/kprobes: Do the notrace functions check without kprobes on ftrace 2021-01-19 18:26:12 +01:00
Makefile
power-traces.c
preemptirq_delay_test.c
ring_buffer.c tracing: Fix race in trace_open and buffer resize call 2021-01-30 13:54:10 +01:00
ring_buffer_benchmark.c
rpm-traces.c
trace.c tracing: Do not stop recording comms if the trace file is being read 2021-06-23 14:41:28 +02:00
trace.h ftrace: Handle tracing when switching between context 2020-11-10 12:37:28 +01:00
trace_benchmark.c
trace_benchmark.h
trace_branch.c
trace_clock.c tracing: Do no increment trace_clock_global() by one 2021-06-23 14:41:28 +02:00
trace_dynevent.c
trace_dynevent.h
trace_entries.h tracing: Set kernel_stack's caller size properly 2020-10-01 13:17:29 +02:00
trace_event_perf.c
trace_events.c tracing: Do not count ftrace events in top level enable output 2021-02-17 10:35:14 +01:00
trace_events_filter.c
trace_events_filter_test.h
trace_events_hist.c tracing/histograms: Fix parsing of "sym-offset" modifier 2021-07-14 16:53:07 +02:00
trace_events_trigger.c
trace_export.c
trace_functions.c
trace_functions_graph.c
trace_hwlat.c tracing: Remove WARN_ON in start_thread() 2020-12-08 10:40:28 +01:00
trace_irqsoff.c
trace_kdb.c
trace_kprobe.c tracing/kprobe: Fix to support kretprobe events on unloaded modules 2021-02-13 13:52:54 +01:00
trace_kprobe_selftest.c
trace_kprobe_selftest.h
trace_mmiotrace.c
trace_nop.c
trace_output.c tracing: Make the space reserved for the pid wider 2020-10-07 08:01:27 +02:00
trace_output.h
trace_preemptirq.c lockdep: fix order in trace_hardirqs_off_caller() 2020-10-01 13:18:14 +02:00
trace_printk.c
trace_probe.c
trace_probe.h
trace_probe_tmpl.h
trace_sched_switch.c
trace_sched_wakeup.c
trace_selftest.c ftrace: Handle tracing when switching between context 2020-11-10 12:37:28 +01:00
trace_selftest_dynamic.c
trace_seq.c
trace_stack.c
trace_stat.c
trace_stat.h
trace_syscalls.c
trace_uprobe.c
tracing_map.c
tracing_map.h