From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Ingo Molnar <mingo@kernel.org>
Cc: linux-kernel@vger.kernel.org,
Li Zhang <zhlcindy@linux.vnet.ibm.com>,
Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>,
Arnaldo Carvalho de Melo <acme@redhat.com>
Subject: [PATCH 24/24] perf symbols: Check access permission when reading symbol files
Date: Fri, 26 Jun 2015 12:45:01 -0300 [thread overview]
Message-ID: <1435333501-3429-25-git-send-email-acme@kernel.org> (raw)
In-Reply-To: <1435333501-3429-1-git-send-email-acme@kernel.org>
From: Li Zhang <zhlcindy@linux.vnet.ibm.com>
There 2 problems when reading symbols files:
* It doesn't report any errors even if when users specify symbol
files which don't exist with --kallsyms or --vmlinux. The result
just shows the address without symbols, which is not what is expected.
So it's better to report errors and exit the program.
* When using command perf report --kallsyms=/proc/kallsyms with a
non-root user, symbols are resolved. Then select one symbol and
annotate it, it reports the error as the following:
Can't annotate __clear_user: No vmlinux file with build id xxx was
found.
The problem is caused by reading /proc/kcore without access permission.
/proc/kcore requires CAP_SYS_RAWIO capability to access, so it needs to
change access permission to allow a specific user to read /proc/kcore or
use root to execute the perf command.
This patch is to report errors when symbol files specified by users
don't exist. And check access permission of /proc/kcore when reading it.
Signed-off-by: Li Zhang <zhlcindy@linux.vnet.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Link: http://lkml.kernel.org/r/1434704253-2632-1-git-send-email-zhlcindy@linux.vnet.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
---
tools/perf/builtin-report.c | 11 +++++++++++
tools/perf/util/symbol.c | 5 ++++-
2 files changed, 15 insertions(+), 1 deletion(-)
diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 32626ea3e227..348bed4a2abf 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -742,6 +742,17 @@ int cmd_report(int argc, const char **argv, const char *prefix __maybe_unused)
argc = parse_options(argc, argv, options, report_usage, 0);
+ if (symbol_conf.vmlinux_name &&
+ access(symbol_conf.vmlinux_name, R_OK)) {
+ pr_err("Invalid file: %s\n", symbol_conf.vmlinux_name);
+ return -EINVAL;
+ }
+ if (symbol_conf.kallsyms_name &&
+ access(symbol_conf.kallsyms_name, R_OK)) {
+ pr_err("Invalid file: %s\n", symbol_conf.kallsyms_name);
+ return -EINVAL;
+ }
+
if (report.use_stdio)
use_browser = 0;
else if (report.use_tui)
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 504f2d73b7ee..48b588c6951a 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1132,8 +1132,11 @@ static int dso__load_kcore(struct dso *dso, struct map *map,
INIT_LIST_HEAD(&md.maps);
fd = open(kcore_filename, O_RDONLY);
- if (fd < 0)
+ if (fd < 0) {
+ pr_err("%s requires CAP_SYS_RAWIO capability to access.\n",
+ kcore_filename);
return -EINVAL;
+ }
/* Read new maps into temporary lists */
err = file__read_maps(fd, md.type == MAP__FUNCTION, kcore_mapfn, &md,
--
2.1.0
next prev parent reply other threads:[~2015-06-26 15:49 UTC|newest]
Thread overview: 26+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-06-26 15:44 [GIT PULL 00/24] perf/core improvements and fixes Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 01/24] perf trace: Validate syscall list passed via -e argument Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 02/24] perf thread_map: Introduce thread_map__reset function Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 03/24] perf thrad_map: Add comm string into array Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 04/24] perf tests: Add thread_map object tests Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 05/24] perf stat: Introduce perf_counts function Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 06/24] perf stat: Use xyarray for cpu evsel counts Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 07/24] perf stat: Make stats work over the thread dimension Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 08/24] perf stat: Rename struct perf_counts::cpu member to values Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 09/24] perf stat: Introduce perf_evlist__reset_stats Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 10/24] perf stat: Move perf_evsel__(alloc|free|reset)_stat_priv into stat object Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 11/24] perf stat: Move perf_evsel__(alloc|free)_prev_raw_counts " Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 12/24] perf stat: Move perf_evlist__(alloc|free|reset)_stats " Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 13/24] perf stat: Introduce perf_evsel__alloc_stats function Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 14/24] perf stat: Introduce perf_evsel__read function Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 15/24] perf stat: Introduce read_counters function Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 16/24] perf stat: Separate counters reading and processing Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 17/24] perf stat: Move zero_per_pkg into counter process code Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 18/24] perf stat: Move perf_stat initialization " Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 19/24] perf stat: Remove perf_evsel__read_cb function Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 20/24] perf stat: Rename print_interval to process_interval Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 21/24] perf stat: Using init_stats instead of memset Arnaldo Carvalho de Melo
2015-06-26 15:44 ` [PATCH 22/24] perf stat: Introduce print_counters function Arnaldo Carvalho de Melo
2015-06-26 15:45 ` [PATCH 23/24] perf stat: Introduce --per-thread option Arnaldo Carvalho de Melo
2015-06-26 15:45 ` Arnaldo Carvalho de Melo [this message]
2015-06-30 4:48 ` [GIT PULL 00/24] perf/core improvements and fixes Ingo Molnar
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1435333501-3429-25-git-send-email-acme@kernel.org \
--to=acme@kernel.org \
--cc=acme@redhat.com \
--cc=linux-kernel@vger.kernel.org \
--cc=mingo@kernel.org \
--cc=sukadev@linux.vnet.ibm.com \
--cc=zhlcindy@linux.vnet.ibm.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).