Ravi Bangoria ba16293dad tracing: Fix kernel crash while using empty filter with perf ... Kernel is crashing when user tries to record 'ftrace:function' event with empty filter: # perf record -e ftrace:function --filter="" ls # dmesg BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 Oops: 0000 [#1] SMP PTI ... RIP: 0010:ftrace_profile_set_filter+0x14b/0x2d0 RSP: 0018:ffffa4a7c0da7d20 EFLAGS: 00010246 RAX: ffffa4a7c0da7d64 RBX: 0000000000000000 RCX: 0000000000000006 RDX: 0000000000000000 RSI: 0000000000000092 RDI: ffff8c48ffc968f0 ... Call Trace: _perf_ioctl+0x54a/0x6b0 ? rcu_all_qs+0x5/0x30 ... After patch: # perf record -e ftrace:function --filter="" ls failed to set filter "" on event ftrace:function with 22 (Invalid argument) Also, if user tries to echo "" > filter, it used to throw an error. This behavior got changed by commit 80765597bc ("tracing: Rewrite filter logic to be simpler and faster"). This patch restores the behavior as a side effect: Before patch: # echo "" > filter # After patch: # echo "" > filter bash: echo: write error: Invalid argument # Link: http://lkml.kernel.org/r/20180420150758.19787-1-ravi.bangoria@linux.ibm.com Fixes: 80765597bc ("tracing: Rewrite filter logic to be simpler and faster") Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>		2018-04-25 10:27:55 -04:00
..
blktrace.c
bpf_trace.c	bpf: Check attach type at prog load time	2018-03-31 02:14:44 +02:00
ftrace.c	ftrace: Drop a VLA in module_exists()	2018-04-06 08:56:48 -04:00
Kconfig	tracing: Add inter-event blurb to HIST_TRIGGERS config option	2018-03-10 16:06:05 -05:00
Makefile
power-traces.c
ring_buffer_benchmark.c
ring_buffer.c	ring-buffer: Add set/clear_current_oom_origin() during allocations	2018-04-06 08:56:52 -04:00
rpm-traces.c
trace_benchmark.c
trace_benchmark.h
trace_branch.c
trace_clock.c	tracing: Hide global trace clock from lockdep	2018-04-06 08:56:52 -04:00
trace_entries.h
trace_event_perf.c	perf/core: Fix perf_uprobe_init()	2018-04-10 07:33:10 +02:00
trace_events_filter_test.h
trace_events_filter.c	tracing: Fix kernel crash while using empty filter with perf	2018-04-25 10:27:55 -04:00
trace_events_hist.c	tracing: Uninitialized variable in create_tracing_map_fields()	2018-04-06 08:56:50 -04:00
trace_events_trigger.c	tracing: Add variable reference handling to hist triggers	2018-03-10 16:05:58 -05:00
trace_events.c	tracing: Make sure the parsed string always terminates with '\0'	2018-01-23 15:57:28 -05:00
trace_export.c
trace_functions_graph.c
trace_functions.c	tracing: Update stack trace skipping for ORC unwinder	2018-01-23 15:57:00 -05:00
trace_hwlat.c
trace_irqsoff.c
trace_kdb.c
trace_kprobe.c	Merge branch 'perf/urgent' into perf/core	2018-03-29 16:03:48 +02:00
trace_mmiotrace.c
trace_nop.c
trace_output.c
trace_output.h
trace_printk.c	treewide: Align function definition open/close braces	2018-03-26 11:13:09 +02:00
trace_probe.c	tracing: probeevent: Fix to support minus offset from symbol	2018-03-23 12:02:37 -04:00
trace_probe.h	Merge branch 'perf/urgent' into perf/core	2018-03-29 16:03:48 +02:00
trace_sched_switch.c
trace_sched_wakeup.c
trace_selftest_dynamic.c	ftrace: Mark function tracer test functions noinline/noclone	2018-01-23 15:57:29 -05:00
trace_selftest.c
trace_seq.c
trace_stack.c	tracing: Have stack trace not record if RCU is not watching	2017-12-14 20:48:22 -05:00
trace_stat.c
trace_stat.h
trace_syscalls.c
trace_uprobe.c	Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2018-04-15 12:36:31 -07:00
trace.c	New features:	2018-04-10 11:27:30 -07:00
trace.h	tracing: Rewrite filter logic to be simpler and faster	2018-03-14 12:35:39 -04:00
tracing_map.c	tracing: Add per-element variable support to tracing_map	2018-03-10 16:05:53 -05:00
tracing_map.h	tracing: Add per-element variable support to tracing_map	2018-03-10 16:05:53 -05:00