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| author |   Wang Nan <wangnan0@huawei.com> | 2015-08-25 13:27:35 +0000 |
|---|---|---|
| committer |   Arnaldo Carvalho de Melo <acme@redhat.com> | 2015-08-26 10:34:11 -0300 |
| commit | e486367f0101d43a044404ed2fa35aa043b19667 (patch) | |
| tree | a60c856163672a05c7d693e1e3a2bedc3ae723c0 /tools | |
| parent | perf tools: Update Intel PT documentation (diff) | |
| download | linux-dev-e486367f0101d43a044404ed2fa35aa043b19667.tar.xz linux-dev-e486367f0101d43a044404ed2fa35aa043b19667.zip | |
perf probe: Prevent segfault when reading probe point with absolute address
'perf probe -l' panic if there is a manually inserted probing point with
absolute address. For example:
# echo 'p:probe/abs_ffffffff811e6615 0xffffffff811e6615' > /sys/kernel/debug/tracing/kprobe_events
# perf probe -l
Segmentation fault (core dumped)
This patch fix this problem by considering the situation that
"tp->symbol == NULL" in find_perf_probe_point_from_dwarf() and
find_perf_probe_point_from_map().
After this patch:
# perf probe -l
probe:abs_ffffffff811e6615 (on SyS_write+5@fs/read_write.c)
And when debug info is missing:
# rm -rf ~/.debug
# mv /lib/modules/4.2.0-rc1+/build/vmlinux /lib/modules/4.2.0-rc1+/build/vmlinux.bak
# perf probe -l
probe:abs_ffffffff811e6615 (on sys_write+5)
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: pi3orama@163.com
Link: http://lkml.kernel.org/r/1440509256-193590-1-git-send-email-wangnan0@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools')
| -rw-r--r-- | tools/perf/util/probe-event.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index f07374bc9c5a..6c7e538c9b8b 100644 --- a/tools/perf/util/probe-event.c +++ b/tools/perf/util/probe-event.c @@ -515,7 +515,7 @@ static int find_perf_probe_point_from_dwarf(struct probe_trace_point *tp, if (ret < 0) goto error; addr += stext; - } else { + } else if (tp->symbol) { addr = kernel_get_symbol_address_by_name(tp->symbol, false); if (addr == 0) goto error; @@ -1815,17 +1815,17 @@ static int find_perf_probe_point_from_map(struct probe_trace_point *tp, { struct symbol *sym = NULL; struct map *map; - u64 addr; + u64 addr = tp->address; int ret = -ENOENT; if (!is_kprobe) { map = dso__new_map(tp->module); if (!map) goto out; - addr = tp->address; sym = map__find_symbol(map, addr, NULL); } else { - addr = kernel_get_symbol_address_by_name(tp->symbol, true); + if (tp->symbol) + addr = kernel_get_symbol_address_by_name(tp->symbol, true); if (addr) { addr += tp->offset; sym = __find_kernel_function(addr, &map); |