Coverity pointed out that we shouldn't be using stat()/open(),
as the file might have vanished or changed in between those
two calls. So modify it to open()/fstat() instead.
Signed-off-by: Hannes Reinecke <hare@xxxxxxxx>
---
libmultipath/sysfs.c | 59 +++++++++++++++++++++++++++++-----------------------
1 file changed, 33 insertions(+), 26 deletions(-)
diff --git a/libmultipath/sysfs.c b/libmultipath/sysfs.c
index de7df40..a74de9f 100644
--- a/libmultipath/sysfs.c
+++ b/libmultipath/sysfs.c
@@ -57,30 +57,31 @@ ssize_t sysfs_attr_get_value(struct udev_device *dev, const char *attr_name,
snprintf(devpath, PATH_SIZE, "%s/%s", udev_device_get_syspath(dev),
attr_name);
condlog(4, "open '%s'", devpath);
- if (stat(devpath, &statbuf) != 0) {
+ /* read attribute value */
+ fd = open(devpath, O_RDONLY);
+ if (fd < 0) {
+ condlog(4, "attribute '%s' can not be opened: %s",
+ devpath, strerror(errno));
+ return -errno;
+ }
+ if (fstat(fd, &statbuf) < 0) {
condlog(4, "stat '%s' failed: %s", devpath, strerror(errno));
+ close(fd);
return -ENXIO;
}
-
/* skip directories */
if (S_ISDIR(statbuf.st_mode)) {
condlog(4, "%s is a directory", devpath);
+ close(fd);
return -EISDIR;
}
-
/* skip non-writeable files */
if ((statbuf.st_mode & S_IRUSR) == 0) {
condlog(4, "%s is not readable", devpath);
+ close(fd);
return -EPERM;
}
- /* read attribute value */
- fd = open(devpath, O_RDONLY);
- if (fd < 0) {
- condlog(4, "attribute '%s' can not be opened: %s",
- devpath, strerror(errno));
- return -errno;
- }
size = read(fd, value, value_len);
if (size < 0) {
condlog(4, "read from %s failed: %s", devpath, strerror(errno));
@@ -112,30 +113,33 @@ ssize_t sysfs_bin_attr_get_value(struct udev_device *dev, const char *attr_name,
snprintf(devpath, PATH_SIZE, "%s/%s", udev_device_get_syspath(dev),
attr_name);
condlog(4, "open '%s'", devpath);
- if (stat(devpath, &statbuf) != 0) {
+ /* read attribute value */
+ fd = open(devpath, O_RDONLY);
+ if (fd < 0) {
+ condlog(4, "attribute '%s' can not be opened: %s",
+ devpath, strerror(errno));
+ return -errno;
+ }
+ if (fstat(fd, &statbuf) != 0) {
condlog(4, "stat '%s' failed: %s", devpath, strerror(errno));
+ close(fd);
return -ENXIO;
}
/* skip directories */
if (S_ISDIR(statbuf.st_mode)) {
condlog(4, "%s is a directory", devpath);
+ close(fd);
return -EISDIR;
}
/* skip non-writeable files */
if ((statbuf.st_mode & S_IRUSR) == 0) {
condlog(4, "%s is not readable", devpath);
+ close(fd);
return -EPERM;
}
- /* read attribute value */
- fd = open(devpath, O_RDONLY);
- if (fd < 0) {
- condlog(4, "attribute '%s' can not be opened: %s",
- devpath, strerror(errno));
- return -errno;
- }
size = read(fd, value, value_len);
if (size < 0) {
condlog(4, "read from %s failed: %s", devpath, strerror(errno));
@@ -163,30 +167,33 @@ ssize_t sysfs_attr_set_value(struct udev_device *dev, const char *attr_name,
snprintf(devpath, PATH_SIZE, "%s/%s", udev_device_get_syspath(dev),
attr_name);
condlog(4, "open '%s'", devpath);
- if (stat(devpath, &statbuf) != 0) {
+ /* write attribute value */
+ fd = open(devpath, O_WRONLY);
+ if (fd < 0) {
+ condlog(4, "attribute '%s' can not be opened: %s",
+ devpath, strerror(errno));
+ return -errno;
+ }
+ if (fstat(fd, &statbuf) != 0) {
condlog(4, "stat '%s' failed: %s", devpath, strerror(errno));
+ close(fd);
return -errno;
}
/* skip directories */
if (S_ISDIR(statbuf.st_mode)) {
condlog(4, "%s is a directory", devpath);
+ close(fd);
return -EISDIR;
}
/* skip non-writeable files */
if ((statbuf.st_mode & S_IWUSR) == 0) {
condlog(4, "%s is not writeable", devpath);
+ close(fd);
return -EPERM;
}
- /* write attribute value */
- fd = open(devpath, O_WRONLY);
- if (fd < 0) {
- condlog(4, "attribute '%s' can not be opened: %s",
- devpath, strerror(errno));
- return -errno;
- }
size = write(fd, value, value_len);
if (size < 0) {
condlog(4, "write to %s failed: %s", devpath, strerror(errno));
--
2.6.6
--
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