From 88bef035149080be5a83f90d91d5b13cec9749e8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>
Date: Fri, 11 Oct 2013 19:33:13 -0400
Subject: [PATCH] Never call qsort on potentially NULL arrays
This extends 62678ded 'efi: never call qsort on potentially
NULL arrays' to all other places where qsort is used and it
is not obvious that the count is non-zero.
---
src/analyze/systemd-analyze.c | 2 +-
src/cgtop/cgtop.c | 2 +-
src/core/namespace.c | 38 ++++++++++++++++++++------------------
src/journal/catalog.c | 2 +-
src/journal/journal-file.c | 2 +-
src/journal/journal-vacuum.c | 3 +--
src/journal/journalctl.c | 2 +-
src/libsystemd-bus/bus-match.c | 2 +-
src/libudev/libudev-enumerate.c | 2 +-
src/nss-myhostname/netlink.c | 3 ++-
src/readahead/readahead-collect.c | 39 ++++++++++++++++++++++-----------------
src/shared/cgroup-show.c | 2 ++
src/shared/conf-files.c | 2 +-
src/shared/efivars.c | 3 +--
src/shared/fileio.c | 1 +
src/shared/util.h | 12 ++++++++++++
src/systemctl/systemctl.c | 10 +++++-----
17 files changed, 74 insertions(+), 53 deletions(-)
diff --git a/src/analyze/systemd-analyze.c b/src/analyze/systemd-analyze.c
index 27d063c..a4f15eb 100644
--- a/src/analyze/systemd-analyze.c
+++ b/src/analyze/systemd-analyze.c
@@ -768,7 +768,7 @@ static int list_dependencies_one(DBusConnection *bus, const char *name, unsigned
if (r < 0)
return r;
- qsort(deps, strv_length(deps), sizeof (char*), list_dependencies_compare);
+ qsort_safe(deps, strv_length(deps), sizeof (char*), list_dependencies_compare);
r = acquire_boot_times(bus, &boot);
if (r < 0)
diff --git a/src/cgtop/cgtop.c b/src/cgtop/cgtop.c
index cacf705..293a211 100644
--- a/src/cgtop/cgtop.c
+++ b/src/cgtop/cgtop.c
@@ -461,7 +461,7 @@ static int display(Hashmap *a) {
if (g->n_tasks_valid || g->cpu_valid || g->memory_valid || g->io_valid)
array[n++] = g;
- qsort(array, n, sizeof(Group*), group_compare);
+ qsort_safe(array, n, sizeof(Group*), group_compare);
/* Find the longest names in one run */
for (j = 0; j < n; j++) {
diff --git a/src/core/namespace.c b/src/core/namespace.c
index 16b132b..936f368 100644
--- a/src/core/namespace.c
+++ b/src/core/namespace.c
@@ -222,7 +222,7 @@ int setup_namespace(char** read_write_dirs,
strv_length(read_only_dirs) +
strv_length(inaccessible_dirs) +
(private_tmp ? 2 : 0);
- BindMount *m, *mounts;
+ BindMount *m, *mounts = NULL;
int r = 0;
if (!mount_flags)
@@ -231,27 +231,29 @@ int setup_namespace(char** read_write_dirs,
if (unshare(CLONE_NEWNS) < 0)
return -errno;
- m = mounts = (BindMount *) alloca(n * sizeof(BindMount));
- if ((r = append_mounts(&m, read_write_dirs, READWRITE)) < 0 ||
- (r = append_mounts(&m, read_only_dirs, READONLY)) < 0 ||
- (r = append_mounts(&m, inaccessible_dirs, INACCESSIBLE)) < 0)
- return r;
+ if (n) {
+ m = mounts = (BindMount *) alloca(n * sizeof(BindMount));
+ if ((r = append_mounts(&m, read_write_dirs, READWRITE)) < 0 ||
+ (r = append_mounts(&m, read_only_dirs, READONLY)) < 0 ||
+ (r = append_mounts(&m, inaccessible_dirs, INACCESSIBLE)) < 0)
+ return r;
+
+ if (private_tmp) {
+ m->path = "/tmp";
+ m->mode = PRIVATE_TMP;
+ m++;
+
+ m->path = "/var/tmp";
+ m->mode = PRIVATE_VAR_TMP;
+ m++;
+ }
- if (private_tmp) {
- m->path = "/tmp";
- m->mode = PRIVATE_TMP;
- m++;
+ assert(mounts + n == m);
- m->path = "/var/tmp";
- m->mode = PRIVATE_VAR_TMP;
- m++;
+ qsort(mounts, n, sizeof(BindMount), mount_path_compare);
+ drop_duplicates(mounts, &n);
}
- assert(mounts + n == m);
-
- qsort(mounts, n, sizeof(BindMount), mount_path_compare);
- drop_duplicates(mounts, &n);
-
/* Remount / as SLAVE so that nothing now mounted in the namespace
shows up in the parent */
if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL) < 0)
diff --git a/src/journal/catalog.c b/src/journal/catalog.c
index 7738d24..90ca008 100644
--- a/src/journal/catalog.c
+++ b/src/journal/catalog.c
@@ -399,7 +399,7 @@ int catalog_update(const char* database, const char* root, const char* const* di
}
assert(n == hashmap_size(h));
- qsort(items, n, sizeof(CatalogItem), catalog_compare_func);
+ qsort_safe(items, n, sizeof(CatalogItem), catalog_compare_func);
r = write_catalog(database, h, sb, items, n);
if (r < 0)
diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c
index 81c344f..425e38a 100644
--- a/src/journal/journal-file.c
+++ b/src/journal/journal-file.c
@@ -1344,7 +1344,7 @@ int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const st
/* Order by the position on disk, in order to improve seek
* times for rotating media. */
- qsort(items, n_iovec, sizeof(EntryItem), entry_item_cmp);
+ qsort_safe(items, n_iovec, sizeof(EntryItem), entry_item_cmp);
r = journal_file_append_entry_internal(f, ts, xor_hash, items, n_iovec, seqnum, ret, offset);
diff --git a/src/journal/journal-vacuum.c b/src/journal/journal-vacuum.c
index 8d5effb..d4a1c6c 100644
--- a/src/journal/journal-vacuum.c
+++ b/src/journal/journal-vacuum.c
@@ -299,8 +299,7 @@ int journal_directory_vacuum(
n_list ++;
}
- if (n_list > 0)
- qsort(list, n_list, sizeof(struct vacuum_info), vacuum_compare);
+ qsort_safe(list, n_list, sizeof(struct vacuum_info), vacuum_compare);
for (i = 0; i < n_list; i++) {
struct statvfs ss;
diff --git a/src/journal/journalctl.c b/src/journal/journalctl.c
index 9a2d255..0876ee6 100644
--- a/src/journal/journalctl.c
+++ b/src/journal/journalctl.c
@@ -755,7 +755,7 @@ static int get_relative_boot_id(sd_journal *j, sd_id128_t *boot_id, int relative
sd_journal_flush_matches(j);
}
- qsort(all_ids, count, sizeof(boot_id_t), boot_id_cmp);
+ qsort_safe(all_ids, count, sizeof(boot_id_t), boot_id_cmp);
if (sd_id128_equal(*boot_id, SD_ID128_NULL)) {
if (relative > (int) count || relative <= -(int)count)
diff --git a/src/libsystemd-bus/bus-match.c b/src/libsystemd-bus/bus-match.c
index 1411167..916682a 100644
--- a/src/libsystemd-bus/bus-match.c
+++ b/src/libsystemd-bus/bus-match.c
@@ -768,7 +768,7 @@ int bus_match_parse(
}
/* Order the whole thing, so that we always generate the same tree */
- qsort(components, n_components, sizeof(struct bus_match_component), match_component_compare);
+ qsort_safe(components, n_components, sizeof(struct bus_match_component), match_component_compare);
/* Check for duplicates */
for (i = 0; i+1 < n_components; i++)
diff --git a/src/libudev/libudev-enumerate.c b/src/libudev/libudev-enumerate.c
index 8146f27..e71d766 100644
--- a/src/libudev/libudev-enumerate.c
+++ b/src/libudev/libudev-enumerate.c
@@ -276,7 +276,7 @@ _public_ struct udev_list_entry *udev_enumerate_get_list_entry(struct udev_enume
size_t move_later_prefix = 0;
udev_list_cleanup(&udev_enumerate->devices_list);
- qsort(udev_enumerate->devices, udev_enumerate->devices_cur, sizeof(struct syspath), syspath_cmp);
+ qsort_safe(udev_enumerate->devices, udev_enumerate->devices_cur, sizeof(struct syspath), syspath_cmp);
max = udev_enumerate->devices_cur;
for (i = 0; i < max; i++) {
diff --git a/src/nss-myhostname/netlink.c b/src/nss-myhostname/netlink.c
index b1ef912..47a41f5 100644
--- a/src/nss-myhostname/netlink.c
+++ b/src/nss-myhostname/netlink.c
@@ -197,7 +197,8 @@ finish:
return r;
}
- qsort(list, n_list, sizeof(struct address), address_compare);
+ if (n_list)
+ qsort(list, n_list, sizeof(struct address), address_compare);
*_list = list;
*_n_list = n_list;
diff --git a/src/readahead/readahead-collect.c b/src/readahead/readahead-collect.c
index 32888ad..6b74866 100644
--- a/src/readahead/readahead-collect.c
+++ b/src/readahead/readahead-collect.c
@@ -536,8 +536,7 @@ done:
HASHMAP_FOREACH_KEY(q, p, files, i)
pack_file(pack, p, on_btrfs);
} else {
- struct item *ordered, *j;
- unsigned k, n;
+ unsigned n;
/* On rotating media, order things by the block
* numbers */
@@ -545,25 +544,31 @@ done:
log_debug("Ordering...");
n = hashmap_size(files);
- if (!(ordered = new(struct item, n))) {
- r = log_oom();
- goto finish;
- }
-
- j = ordered;
- HASHMAP_FOREACH_KEY(q, p, files, i) {
- memcpy(j, q, sizeof(struct item));
- j++;
- }
+ if (n) {
+ _cleanup_free_ struct item *ordered;
+ struct item *j;
+ unsigned k;
+
+ ordered = new(struct item, n);
+ if (!ordered) {
+ r = log_oom();
+ goto finish;
+ }
- assert(ordered + n == j);
+ j = ordered;
+ HASHMAP_FOREACH_KEY(q, p, files, i) {
+ memcpy(j, q, sizeof(struct item));
+ j++;
+ }
- qsort(ordered, n, sizeof(struct item), qsort_compare);
+ assert(ordered + n == j);
- for (k = 0; k < n; k++)
- pack_file(pack, ordered[k].path, on_btrfs);
+ qsort(ordered, n, sizeof(struct item), qsort_compare);
- free(ordered);
+ for (k = 0; k < n; k++)
+ pack_file(pack, ordered[k].path, on_btrfs);
+ } else
+ log_warning("No pack files");
}
log_debug("Finalizing...");
diff --git a/src/shared/cgroup-show.c b/src/shared/cgroup-show.c
index e971f36..cc44ab4 100644
--- a/src/shared/cgroup-show.c
+++ b/src/shared/cgroup-show.c
@@ -44,6 +44,8 @@ static void show_pid_array(int pids[], unsigned n_pids, const char *prefix, unsi
unsigned i, m, pid_width;
pid_t biggest = 0;
+ assert(n_pids > 0);
+
/* Filter duplicates */
m = 0;
for (i = 0; i < n_pids; i++) {
diff --git a/src/shared/conf-files.c b/src/shared/conf-files.c
index 6d99739..ed4070c 100644
--- a/src/shared/conf-files.c
+++ b/src/shared/conf-files.c
@@ -127,7 +127,7 @@ static int conf_files_list_strv_internal(char ***strv, const char *suffix, const
return -ENOMEM;
}
- qsort(files, hashmap_size(fh), sizeof(char *), base_cmp);
+ qsort_safe(files, hashmap_size(fh), sizeof(char *), base_cmp);
*strv = files;
hashmap_free(fh);
diff --git a/src/shared/efivars.c b/src/shared/efivars.c
index c015b16..f3eb6a6 100644
--- a/src/shared/efivars.c
+++ b/src/shared/efivars.c
@@ -384,8 +384,7 @@ int efi_get_boot_options(uint16_t **options) {
list[count ++] = id;
}
- if (list)
- qsort(list, count, sizeof(uint16_t), cmp_uint16);
+ qsort_safe(list, count, sizeof(uint16_t), cmp_uint16);
*options = list;
return count;
diff --git a/src/shared/fileio.c b/src/shared/fileio.c
index 603a1c7..733b320 100644
--- a/src/shared/fileio.c
+++ b/src/shared/fileio.c
@@ -662,6 +662,7 @@ int get_status_field(const char *filename, const char *pattern, char **field) {
int r;
assert(filename);
+ assert(pattern);
assert(field);
r = read_full_file(filename, &status, NULL);
diff --git a/src/shared/util.h b/src/shared/util.h
index 1b845b3..222abe0 100644
--- a/src/shared/util.h
+++ b/src/shared/util.h
@@ -764,3 +764,15 @@ bool id128_is_valid(const char *s) _pure_;
void parse_user_at_host(char *arg, char **user, char **host);
int split_pair(const char *s, const char *sep, char **l, char **r);
+
+/**
+ * Normal qsort requires base to be nonnull. Here were require
+ * that only if nmemb > 0.
+ */
+static inline void qsort_safe(void *base, size_t nmemb, size_t size,
+ int (*compar)(const void *, const void *)) {
+ if (nmemb) {
+ assert(base);
+ qsort(base, nmemb, size, compar);
+ }
+}
diff --git a/src/systemctl/systemctl.c b/src/systemctl/systemctl.c
index d75281f..036828b 100644
--- a/src/systemctl/systemctl.c
+++ b/src/systemctl/systemctl.c
@@ -471,7 +471,7 @@ static int list_units(DBusConnection *bus, char **args) {
if (r < 0)
return r;
- qsort(unit_infos, c, sizeof(struct unit_info), compare_unit_info);
+ qsort_safe(unit_infos, c, sizeof(struct unit_info), compare_unit_info);
output_units_list(unit_infos, c);
@@ -733,8 +733,8 @@ static int list_sockets(DBusConnection *bus, char **args) {
listen = triggered = NULL; /* avoid cleanup */
}
- qsort(socket_infos, cs, sizeof(struct socket_info),
- (__compar_fn_t) socket_info_compare);
+ qsort_safe(socket_infos, cs, sizeof(struct socket_info),
+ (__compar_fn_t) socket_info_compare);
output_sockets_list(socket_infos, cs);
@@ -1108,7 +1108,7 @@ static int list_dependencies_one(DBusConnection *bus, const char *name, int leve
if (r < 0)
return r;
- qsort(deps, strv_length(deps), sizeof (char*), list_dependencies_compare);
+ qsort_safe(deps, strv_length(deps), sizeof (char*), list_dependencies_compare);
STRV_FOREACH(c, deps) {
if (strv_contains(u, *c)) {
@@ -3532,7 +3532,7 @@ static int show_all(const char* verb,
if (r < 0)
return r;
- qsort(unit_infos, c, sizeof(struct unit_info), compare_unit_info);
+ qsort_safe(unit_infos, c, sizeof(struct unit_info), compare_unit_info);
for (u = unit_infos; u < unit_infos + c; u++) {
_cleanup_free_ char *p = NULL;