[PATCH] libsepol: check strdup() failures and replace constant

[Jokke Hämäläinen <jokke.hamalainen@xxxxxxxxxxxx>]

Check for strdup() failures. Also replace constant 18
with a safer sizeof() use.

Signed-off-by: Unto Sten <sten.unto@xxxxxxxxx>
---
 libsepol/src/kernel_to_conf.c | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/libsepol/src/kernel_to_conf.c b/libsepol/src/kernel_to_conf.c
index 4f84ee8b..930bafab 100644
--- a/libsepol/src/kernel_to_conf.c
+++ b/libsepol/src/kernel_to_conf.c
@@ -448,8 +448,12 @@ static int write_sids_to_conf(FILE *out, const char *const *sid_to_str,
 		if (i < num_sids) {
 			sid = (char *)sid_to_str[i];
 		} else {
-			snprintf(unknown, 18, "%s%u", "UNKNOWN", i);
+			snprintf(unknown, sizeof(unknown), "%s%u", "UNKNOWN", i);
 			sid = strdup(unknown);
+			if (!sid) {
+				rc = -1;
+				goto exit;
+			}
 		}
 		rc = strs_add_at_index(strs, sid, i);
 		if (rc != 0) {
@@ -792,6 +796,10 @@ static int write_sensitivity_rules_to_conf(FILE *out, struct policydb *pdb)
 			j = level->level->sens - 1;
 			if (!sens_alias_map[j]) {
 				sens_alias_map[j] = strdup(name);
+				if (!sens_alias_map[j]) {
+					rc = -1;
+					goto exit;
+				}
 			} else {
 				alias = sens_alias_map[j];
 				sens_alias_map[j] = create_str("%s %s", 2, alias, name);
@@ -919,6 +927,10 @@ static int write_category_rules_to_conf(FILE *out, struct policydb *pdb)
 			j = cat->s.value - 1;
 			if (!cat_alias_map[j]) {
 				cat_alias_map[j] = strdup(name);
+				if (!cat_alias_map[j]) {
+					rc = -1;
+					goto exit;
+				}
 			} else {
 				alias = cat_alias_map[j];
 				cat_alias_map[j] = create_str("%s %s", 2, alias, name);
@@ -2364,7 +2376,7 @@ static int write_sid_context_rules_to_conf(FILE *out, struct policydb *pdb, cons
 		if (i < num_sids) {
 			sid = (char *)sid_to_str[i];
 		} else {
-			snprintf(unknown, 18, "%s%u", "UNKNOWN", i);
+			snprintf(unknown, sizeof(unknown), "%s%u", "UNKNOWN", i);
 			sid = unknown;
 		}
 
-- 
2.21.0