perf probe: Fix to avoid crashing if DW_AT_decl_file is NULL

Browse source

Since clang generates DWARF5 which sets DW_AT_decl_file as 0,
dwarf_decl_file() thinks that is invalid and returns NULL.  In that case
'perf probe' SIGSEGVs because it doesn't expect a NULL decl_file.

This adds a dwarf_decl_file() return value check to avoid such SEGV with
clang generated DWARF5 info.

Without this, 'perf probe' crashes:

  $ perf probe -k $BIN_PATH/vmlinux -s $SRC_PATH -L vfs_read:10
  Segmentation fault
  $

With this, it just warns about it:

  $ perf probe -k $BIN_PATH/vmlinux -s $SRC_PATH -L vfs_read:10
  Debuginfo analysis failed.
    Error: Failed to show lines.
  $

Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/166731051077.2100653.15626653369345128302.stgit@devnote3
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

...

This commit is contained in:

Masami Hiramatsu (Google) 2022-11-01 22:48:30 +09:00 • committed by Arnaldo Carvalho de Melo

parent 940da138b0

commit 98e4c68ddc

2 changed files with 27 additions and 9 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

7

tools/perf/util/dwarf-aux.c

View file

29

tools/perf/util/probe-finder.c

View file