android_kernel_motorola_sm6375/kernel/trace
Repository files (latest commit first)
Filename Latest commit message Latest commit date
Steven Rostedt (VMware) 558ab52776 tracing: Fix stack trace event size
commit 9deb193af69d3fd6dd8e47f292b67c805a787010 upstream.

Commit cbc3b92ce037 fixed an issue to modify the macros of the stack trace
event so that user space could parse it properly. Originally the stack
trace format to user space showed that the called stack was a dynamic
array. But it is not actually a dynamic array, in the way that other
dynamic event arrays worked, and this broke user space parsing for it. The
update was to make the array look to have 8 entries in it. Helper
functions were added to make it parse it correctly, as the stack was
dynamic, but was determined by the size of the event stored.

Although this fixed user space on how it read the event, it changed the
internal structure used for the stack trace event. It changed the array
size from [0] to [8] (added 8 entries). This increased the size of the
stack trace event by 8 words. The size reserved on the ring buffer was the
size of the stack trace event plus the number of stack entries found in
the stack trace. That commit caused the amount to be 8 more than what was
needed because it did not expect the caller field to have any size. This
produced 8 entries of garbage (and reading random data) from the stack
trace event:

          <idle>-0       [002] d... 1976396.837549: <stack trace>
 => trace_event_raw_event_sched_switch
 => __traceiter_sched_switch
 => __schedule
 => schedule_idle
 => do_idle
 => cpu_startup_entry
 => secondary_startup_64_no_verify
 => 0xc8c5e150ffff93de
 => 0xffff93de
 => 0
 => 0
 => 0xc8c5e17800000000
 => 0x1f30affff93de
 => 0x00000004
 => 0x200000000

Instead, subtract the size of the caller field from the size of the event
to make sure that only the amount needed to store the stack trace is
reserved.

Link: https://lore.kernel.org/lkml/your-ad-here.call-01617191565-ext-9692@work.hours/

Cc: stable@vger.kernel.org
Fixes: cbc3b92ce037 ("tracing: Set kernel_stack's caller size properly")
Reported-by: Vasily Gorbik <gor@linux.ibm.com>
Tested-by: Vasily Gorbik <gor@linux.ibm.com>
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-04-07 14:47:42 +02:00
..
blktrace.c
bpf_trace.c bpf: Fix bpf_put_raw_tracepoint()'s use of __module_address() 2020-12-30 11:51:18 +01:00
fgraph.c fgraph: Initialize tracing_graph_pause at task creation 2021-02-10 09:25:29 +01:00
ftrace.c ftrace: Fix updating FTRACE_FL_TRAMP 2020-12-11 13:23:29 +01:00
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: Fix stack trace event size 2021-04-07 14:47:42 +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
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: fix double free 2020-10-01 13:18:23 +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