A segmentation fault is produced when applying an input JSON file like the following: {"nftables": [ { "add": {"map": {"family": "ip", "name": "persistencia", "table": "nftlb", "type": "ipv4_addr", "map": "mark", "size": 65535, "flags": ["timeout"], "timeout": 44 } } } ]} The captured error is: Program received signal SIGSEGV, Segmentation fault. #1 0x00007ffff7f734f9 in string_to_nft_object (str=0x55555555f410 "mark") at parser_json.c:2513 2513 if (!strcmp(str, obj_tbl[i])) The obj_tbl array is allocated with the maximum element index even if lower indexes are not populated, so it produces null pointer items. This patch ensures that the maximum number of possible indexes but also the element is not comparing a null pointer. Signed-off-by: Laura Garcia Liebana <nevola@xxxxxxxxx> --- src/parser_json.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/src/parser_json.c b/src/parser_json.c index 827604b..d0eacb6 100644 --- a/src/parser_json.c +++ b/src/parser_json.c @@ -2500,17 +2500,18 @@ static struct cmd *json_parse_cmd_add_rule(struct json_ctx *ctx, json_t *root, static int string_to_nft_object(const char *str) { - const char *obj_tbl[] = { + const char *obj_tbl[__NFT_OBJECT_MAX] = { [NFT_OBJECT_COUNTER] = "counter", [NFT_OBJECT_QUOTA] = "quota", [NFT_OBJECT_CT_HELPER] = "ct helper", [NFT_OBJECT_LIMIT] = "limit", [NFT_OBJECT_SECMARK] = "secmark", }; + unsigned int i; - for (i = 1; i < array_size(obj_tbl); i++) { - if (!strcmp(str, obj_tbl[i])) + for (i = 0; i < NFT_OBJECT_MAX; i++) { + if (obj_tbl[i] && !strcmp(str, obj_tbl[i])) return i; } return 0; -- 2.11.0