From 3bf2ca11d9ce4ce205a98828ec4bfe8169c33403 Mon Sep 17 00:00:00 2001 From: Zdenek Kabelac Date: Sun, 7 Feb 2021 14:07:17 +0100 Subject: [PATCH] dev-type: use fopen for sysfs file Directly open sysfs files and save extra stat() call which is not adding any extra safety in sysfs dir. --- lib/device/dev-type.c | 18 ++++++------------ 1 file changed, 6 insertions(+), 12 deletions(-) diff --git a/lib/device/dev-type.c b/lib/device/dev-type.c index dca81d8d1..c9f12d793 100644 --- a/lib/device/dev-type.c +++ b/lib/device/dev-type.c @@ -944,8 +944,7 @@ static unsigned long _dev_topology_attribute(struct dev_types *dt, const char *sysfs_dir = dm_sysfs_dir(); char path[PATH_MAX], buffer[64]; FILE *fp; - struct stat info; - dev_t uninitialized_var(primary); + dev_t primary = 0; unsigned long result = default_value; unsigned long value = 0UL; @@ -963,9 +962,9 @@ static unsigned long _dev_topology_attribute(struct dev_types *dt, * - if not: either the kernel doesn't have topology support * or the device could be a partition */ - if (stat(path, &info) == -1) { + if (!(fp = fopen(path, "r"))) { if (errno != ENOENT) { - log_sys_debug("stat", path); + log_sys_debug("fopen", path); goto out; } if (!dev_get_primary_dev(dt, dev, &primary)) @@ -975,25 +974,20 @@ static unsigned long _dev_topology_attribute(struct dev_types *dt, if (!_snprintf_attr(path, sizeof(path), sysfs_dir, attribute, primary)) goto_out; - if (stat(path, &info) == -1) { + if (!(fp = fopen(path, "r"))) { if (errno != ENOENT) - log_sys_debug("stat", path); + log_sys_debug("fopen", path); goto out; } } - if (!(fp = fopen(path, "r"))) { - log_sys_debug("fopen", path); - goto out; - } - if (!fgets(buffer, sizeof(buffer), fp)) { log_sys_debug("fgets", path); goto out_close; } if (sscanf(buffer, "%lu", &value) != 1) { - log_warn("sysfs file %s not in expected format: %s", path, buffer); + log_warn("WARNING: sysfs file %s not in expected format: %s", path, buffer); goto out_close; }