File fix-ambiguous-parsing-of-node-entries-in-sys.patch of Package irqbalance

Overview Repositories Revisions Requests Users Attributes Meta

File fix-ambiguous-parsing-of-node-entries-in-sys.patch of Package irqbalance (Revision 4b8b10e610c8e88db3e6839b6a417ec4)

Currently displaying revision 4b8b10e610c8e88db3e6839b6a417ec4 , Show latest

From 4ca0bf823ea135514b7c3d26f98586c01baf1e42 Mon Sep 17 00:00:00 2001
From: Gerd Rausch <gerd.rausch@oracle.com>
Date: Thu, 18 Oct 2018 11:21:40 -0700
Subject: [PATCH 1/1] Fix ambiguous parsing of *node* entries in /sys.

The code used to use strstr(..., "node") while iterating over
sysfs directories such as /sys/devices/system/cpu/cpu*.
It then made an assumption that the entry would start with "node",
which is not necessarily the case (e.g. the "firmware_node" entry).

The code happened to work for as long as the node[0-9]* entry
would be processed before the "firmware_node" entry shows up.

A change to the linux kernel "end_name_hash" function resulted
in a different hash, and ultimately in a different order
by which entries were returned by readdir(3).

This led to the exposure of this bug.

Signed-off-by: Gerd Rausch <gerd.rausch@oracle.com>
---
 cputree.c | 11 ++++++++---
 numa.c    |  5 ++++-
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/cputree.c b/cputree.c
index d09af43..e2541aa 100644
--- a/cputree.c
+++ b/cputree.c
@@ -361,9 +361,14 @@ static void do_one_cpu(char *path)
 			entry = readdir(dir);
 			if (!entry)
 				break;
-			if (strstr(entry->d_name, "node")) {
-				nodeid = strtoul(&entry->d_name[4], NULL, 10);
-				break;
+			if (strncmp(entry->d_name, "node", 4) == 0) {
+				char *end;
+				int num;
+				num = strtol(entry->d_name + 4, &end, 10);
+				if (!*end && num >= 0) {
+					nodeid = num;
+					break;
+				}
 			}
 		} while (entry);
 		closedir(dir);
diff --git a/numa.c b/numa.c
index cd67ec8..f0b1a98 100644
--- a/numa.c
+++ b/numa.c
@@ -29,6 +29,7 @@
 #include <unistd.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <ctype.h>
 #include <sys/types.h>
 #include <dirent.h>
 
@@ -115,7 +116,9 @@ void build_numa_node_list(void)
 		entry = readdir(dir);
 		if (!entry)
 			break;
-		if ((entry->d_type == DT_DIR) && (strstr(entry->d_name, "node"))) {
+		if ((entry->d_type == DT_DIR) &&
+		    (strncmp(entry->d_name, "node", 4) == 0) &&
+		    isdigit(entry->d_name[4])) {
 			add_one_node(entry->d_name);
 		}
 	} while (entry);
-- 
2.30.1

Places

File fix-ambiguous-parsing-of-node-entries-in-sys.patch of Package irqbalance (Revision 4b8b10e610c8e88db3e6839b6a417ec4)

Places