This reverts commit 4d436e4bf80284ac3b645bad022a9757dbc2dd36.
Needed to revert commit 92306daf5219e73f6e8bc9fc7699399457999bcd
"libselinux: rework selabel_file(5) database", which broke Android
file_context matching.
Signed-off-by: James Carter <jwcart2@xxxxxxxxx>
---
libselinux/src/label_file.c | 129 +++++++++++++++++-------------------
libselinux/src/label_file.h | 20 ++----
2 files changed, 66 insertions(+), 83 deletions(-)
diff --git a/libselinux/src/label_file.c b/libselinux/src/label_file.c
index b7ff8c09..be1ee11a 100644
--- a/libselinux/src/label_file.c
+++ b/libselinux/src/label_file.c
@@ -1188,27 +1188,28 @@ static int process_file(const char *path, const char *suffix,
return -1;
}
-static void selabel_subs_fini(struct selabel_sub *subs, uint32_t num)
+static void selabel_subs_fini(struct selabel_sub *ptr)
{
- for (uint32_t i = 0; i < num; i++) {
- free(subs[i].src);
- free(subs[i].dst);
+ struct selabel_sub *next;
+
+ while (ptr) {
+ next = ptr->next;
+ free(ptr->src);
+ free(ptr->dst);
+ free(ptr);
+ ptr = next;
}
-
- free(subs);
}
-static char *selabel_apply_subs(const struct selabel_sub *subs, uint32_t num, const char *src)
+static char *selabel_sub(const struct selabel_sub *ptr, const char *src)
{
- char *dst;
- uint32_t len;
-
- for (uint32_t i = 0; i < num; i++) {
- const struct selabel_sub *ptr = &subs[i];
+ char *dst = NULL;
+ unsigned int len;
+ while (ptr) {
if (strncmp(src, ptr->src, ptr->slen) == 0 ) {
if (src[ptr->slen] == '/' ||
- src[ptr->slen] == '\0') {
+ src[ptr->slen] == 0) {
if ((src[ptr->slen] == '/') &&
(strcmp(ptr->dst, "/") == 0))
len = ptr->slen + 1;
@@ -1219,38 +1220,34 @@ static char *selabel_apply_subs(const struct selabel_sub *subs, uint32_t num, co
return dst;
}
}
+ ptr = ptr->next;
}
-
return NULL;
}
#if !defined(BUILD_HOST) && !defined(ANDROID)
static int selabel_subs_init(const char *path, struct selabel_digest *digest,
- struct selabel_sub **out_subs,
- uint32_t *out_num, uint32_t *out_alloc)
+ struct selabel_sub **out_subs)
{
char buf[1024];
- FILE *cfg;
+ FILE *cfg = fopen(path, "re");
+ struct selabel_sub *list = NULL, *sub = NULL;
struct stat sb;
- struct selabel_sub *tmp = NULL;
- uint32_t tmp_num = 0, tmp_alloc = 0;
- char *src_cpy = NULL, *dst_cpy = NULL;
- int rc;
+ int status = -1;
*out_subs = NULL;
- *out_num = 0;
- *out_alloc = 0;
-
- cfg = fopen(path, "re");
if (!cfg) {
/* If the file does not exist, it is not fatal */
return (errno == ENOENT) ? 0 : -1;
}
+ if (fstat(fileno(cfg), &sb) < 0)
+ goto out;
+
while (fgets_unlocked(buf, sizeof(buf) - 1, cfg)) {
- char *ptr;
+ char *ptr = NULL;
char *src = buf;
- char *dst;
+ char *dst = NULL;
size_t len;
while (*src && isspace((unsigned char)*src))
@@ -1278,68 +1275,62 @@ static int selabel_subs_init(const char *path, struct selabel_digest *digest,
goto err;
}
- src_cpy = strdup(src);
- if (!src_cpy)
+ sub = calloc(1, sizeof(*sub));
+ if (! sub)
goto err;
- dst_cpy = strdup(dst);
- if (!dst_cpy)
+ sub->src = strdup(src);
+ if (! sub->src)
goto err;
- rc = GROW_ARRAY(tmp);
- if (rc)
+ sub->dst = strdup(dst);
+ if (! sub->dst)
goto err;
- tmp[tmp_num++] = (struct selabel_sub) {
- .src = src_cpy,
- .slen = len,
- .dst = dst_cpy,
- };
- src_cpy = NULL;
- dst_cpy = NULL;
+ sub->slen = len;
+ sub->next = list;
+ list = sub;
+ sub = NULL;
}
- rc = fstat(fileno(cfg), &sb);
- if (rc < 0)
- goto err;
-
if (digest_add_specfile(digest, cfg, NULL, sb.st_size, path) < 0)
goto err;
- *out_subs = tmp;
- *out_num = tmp_num;
- *out_alloc = tmp_alloc;
+ *out_subs = list;
+ status = 0;
+out:
fclose(cfg);
-
- return 0;
-
+ return status;
err:
- free(dst_cpy);
- free(src_cpy);
- for (uint32_t i = 0; i < tmp_num; i++) {
- free(tmp[i].src);
- free(tmp[i].dst);
+ if (sub)
+ free(sub->src);
+ free(sub);
+ while (list) {
+ sub = list->next;
+ free(list->src);
+ free(list->dst);
+ free(list);
+ list = sub;
}
- free(tmp);
- fclose_errno_safe(cfg);
- return -1;
+ goto out;
}
#endif
static char *selabel_sub_key(const struct saved_data *data, const char *key)
{
- char *ptr, *dptr;
+ char *ptr = NULL;
+ char *dptr = NULL;
- ptr = selabel_apply_subs(data->subs, data->subs_num, key);
+ ptr = selabel_sub(data->subs, key);
if (ptr) {
- dptr = selabel_apply_subs(data->dist_subs, data->dist_subs_num, ptr);
+ dptr = selabel_sub(data->dist_subs, ptr);
if (dptr) {
free(ptr);
ptr = dptr;
}
} else {
- ptr = selabel_apply_subs(data->dist_subs, data->dist_subs_num, key);
+ ptr = selabel_sub(data->dist_subs, key);
}
return ptr;
@@ -1384,25 +1375,23 @@ static int init(struct selabel_handle *rec, const struct selinux_opt *opts,
if (!path) {
status = selabel_subs_init(
selinux_file_context_subs_dist_path(),
- rec->digest,
- &data->dist_subs, &data->dist_subs_num, &data->dist_subs_alloc);
+ rec->digest, &data->dist_subs);
if (status)
goto finish;
status = selabel_subs_init(selinux_file_context_subs_path(),
- rec->digest,
- &data->subs, &data->subs_num, &data->subs_alloc);
+ rec->digest, &data->subs);
if (status)
goto finish;
path = selinux_file_context_path();
} else {
snprintf(subs_file, sizeof(subs_file), "%s.subs_dist", path);
status = selabel_subs_init(subs_file, rec->digest,
- &data->dist_subs, &data->dist_subs_num, &data->dist_subs_alloc);
+ &data->dist_subs);
if (status)
goto finish;
snprintf(subs_file, sizeof(subs_file), "%s.subs", path);
status = selabel_subs_init(subs_file, rec->digest,
- &data->subs, &data->subs_num, &data->subs_alloc);
+ &data->subs);
if (status)
goto finish;
}
@@ -1470,8 +1459,8 @@ static void closef(struct selabel_handle *rec)
if (!data)
return;
- selabel_subs_fini(data->subs, data->subs_num);
- selabel_subs_fini(data->dist_subs, data->dist_subs_num);
+ selabel_subs_fini(data->subs);
+ selabel_subs_fini(data->dist_subs);
free_spec_node(data->root);
free(data->root);
diff --git a/libselinux/src/label_file.h b/libselinux/src/label_file.h
index d5dd2be1..b59db003 100644
--- a/libselinux/src/label_file.h
+++ b/libselinux/src/label_file.h
@@ -67,11 +67,11 @@ extern struct lookup_result *lookup_all(struct selabel_handle *rec, const char *
extern enum selabel_cmp_result cmp(const struct selabel_handle *h1, const struct selabel_handle *h2);
#endif /* FUZZING_BUILD_MODE_UNSAFE_FOR_PRODUCTION */
-/* A path substitution entry */
struct selabel_sub {
- char *src; /* source path prefix */
- char *dst; /* substituted path prefix */
- uint32_t slen; /* length of source path prefix */
+ char *src;
+ unsigned int slen;
+ char *dst;
+ struct selabel_sub *next;
};
/* A regular expression file security context specification */
@@ -159,17 +159,9 @@ struct saved_data {
struct mmap_area *mmap_areas;
- /*
- * Array of distribution substitutions
- */
+ /* substitution support */
struct selabel_sub *dist_subs;
- uint32_t dist_subs_num, dist_subs_alloc;
-
- /*
- * Array of local substitutions
- */
struct selabel_sub *subs;
- uint32_t subs_num, subs_alloc;
};
void free_spec_node(struct spec_node *node);
@@ -795,6 +787,8 @@ static int insert_spec(const struct selabel_handle *rec, struct saved_data *data
return 0;
}
+#undef GROW_ARRAY
+
/* This will always check for buffer over-runs and either read the next entry
* if buf != NULL or skip over the entry (as these areas are mapped in the
* current buffer). */
--
2.47.1
