From: Sam Bobroff <sam.bobroff@au1.ibm.com>
To: linux-numa@vger.kernel.org
Subject: [PATCH 1/1] numastat: fix memory overwrite with -p <pid>
Date: Tue, 2 Aug 2016 13:19:06 +1000 [thread overview]
Message-ID: <a4bec8779de359d012b052a482c3edfa00fdde11.1470107943.git.sam.bobroff@au1.ibm.com> (raw)
Fix a memory overrun when using -p with a single pid on a machine
with non-consecutive NUMA nodes, due to the node number being used
instead of the node index.
Correct this by adding a function to find the index of a node number
by searching through the node indices list.
Signed-off-by: Sam Bobroff <sam.bobroff@au1.ibm.com>
---
Hi,
I've found that "numastat -p <pid>" segfaults on machines that have
non-consecutive NUMA nodes. The machine I discovered it on had two
nodes, 0 and 8.
Here's a patch that fixes the problem for me. I'm not sure if this is
the best fix, particularly the linear search over nodes, but maybe
it's OK. It does at least explain what I think is happening.
Cheers,
Sam.
numastat.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/numastat.c b/numastat.c
index 1924dba..e5eebd7 100644
--- a/numastat.c
+++ b/numastat.c
@@ -933,6 +933,17 @@ void show_system_info() {
}
+int node_num_to_ix(int node_num) {
+ for (int node_ix = 0; (node_ix < num_nodes); node_ix++) {
+ if (node_ix_map[node_ix] == node_num) {
+ return node_ix;
+ }
+ }
+ perror("unknown node in numa map");
+ exit(EXIT_FAILURE);
+}
+
+
void show_process_info() {
vtab_t table;
int header_rows = 2;
@@ -1035,7 +1046,7 @@ void show_process_info() {
// node number and accumulate the number of pages in the specific
// category (and also add to the total).
if (p[0] == 'N') {
- int node_num = (int)strtol(&p[1], &p, 10);
+ int node_ix = node_num_to_ix((int)strtol(&p[1], &p, 10));
if (p[0] != '=') {
perror("node value parse error");
exit(EXIT_FAILURE);
@@ -1054,7 +1065,7 @@ void show_process_info() {
} else {
tmp_row = header_rows + pid_ix;
}
- int tmp_col = header_cols + node_num;
+ int tmp_col = header_cols + node_ix;
double_addto(&table, tmp_row, tmp_col, value);
double_addto(&table, tmp_row, total_col_ix, value);
double_addto(&table, total_row_ix, tmp_col, value);
--
2.1.0
reply other threads:[~2016-08-02 3:19 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
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=a4bec8779de359d012b052a482c3edfa00fdde11.1470107943.git.sam.bobroff@au1.ibm.com \
--to=sam.bobroff@au1.ibm.com \
--cc=linux-numa@vger.kernel.org \
/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 read-only IMAP folder(s) and NNTP newsgroup(s).