Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752685AbbH1GlY (ORCPT ); Fri, 28 Aug 2015 02:41:24 -0400 Received: from terminus.zytor.com ([198.137.202.10]:54753 "EHLO terminus.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751525AbbH1GlU (ORCPT ); Fri, 28 Aug 2015 02:41:20 -0400 Date: Thu, 27 Aug 2015 23:40:56 -0700 From: tip-bot for Wang Nan Message-ID: Cc: acme@redhat.com, linux-kernel@vger.kernel.org, masami.hiramatsu.pt@hitachi.com, mingo@kernel.org, wangnan0@huawei.com, namhyung@kernel.org, tglx@linutronix.de, hpa@zytor.com Reply-To: acme@redhat.com, mingo@kernel.org, wangnan0@huawei.com, masami.hiramatsu.pt@hitachi.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, namhyung@kernel.org, hpa@zytor.com In-Reply-To: <1440509256-193590-1-git-send-email-wangnan0@huawei.com> References: <1440509256-193590-1-git-send-email-wangnan0@huawei.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf probe: Prevent segfault when reading probe point with absolute address Git-Commit-ID: e486367f0101d43a044404ed2fa35aa043b19667 X-Mailer: tip-git-log-daemon Robot-ID: Robot-Unsubscribe: Contact to get blacklisted from these emails MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2885 Lines: 82 Commit-ID: e486367f0101d43a044404ed2fa35aa043b19667 Gitweb: http://git.kernel.org/tip/e486367f0101d43a044404ed2fa35aa043b19667 Author: Wang Nan AuthorDate: Tue, 25 Aug 2015 13:27:35 +0000 Committer: Arnaldo Carvalho de Melo CommitDate: Wed, 26 Aug 2015 10:34:11 -0300 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 Tested-by: Arnaldo Carvalho de Melo Acked-by: Masami Hiramatsu Cc: Namhyung Kim 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 --- tools/perf/util/probe-event.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/tools/perf/util/probe-event.c b/tools/perf/util/probe-event.c index f07374b..6c7e538 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); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/