diff options
| author | Pablo Neira Ayuso <pablo@netfilter.org> | 2020-02-19 21:05:26 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2020-02-19 21:23:34 +0100 |
| commit | 78bbe7f7a55be48909067e25900de27623d8fa6a (patch) | |
| tree | 203fc630e89a9dbcfca98b9250d8113ee646937f | |
| parent | f027cbf82445eec0c0f43e0025b5427bea467958 (diff) | |
mnl: do not use expr->identifier to fetch device name
This string might not be nul-terminated, resulting in spurious errors
when adding netdev chains.
Fixes: 3fdc7541fba0 ("src: add multidevice support for netdev chain")
Fixes: 92911b362e90 ("src: add support to add flowtables")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | src/mnl.c | 33 | ||||
| -rw-r--r-- | src/parser_bison.y | 6 |
2 files changed, 32 insertions, 7 deletions
@@ -26,6 +26,7 @@ #include <mnl.h> #include <string.h> +#include <net/if.h> #include <sys/socket.h> #include <arpa/inet.h> #include <fcntl.h> @@ -609,7 +610,9 @@ int mnl_nft_chain_add(struct netlink_ctx *ctx, struct cmd *cmd, { int priority, policy, i = 0; struct nftnl_chain *nlc; + unsigned int ifname_len; const char **dev_array; + char ifname[IFNAMSIZ]; struct nlmsghdr *nlh; struct expr *expr; int dev_array_len; @@ -635,7 +638,12 @@ int mnl_nft_chain_add(struct netlink_ctx *ctx, struct cmd *cmd, dev_array = xmalloc(sizeof(char *) * 8); dev_array_len = 8; list_for_each_entry(expr, &cmd->chain->dev_expr->expressions, list) { - dev_array[i++] = expr->identifier; + ifname_len = div_round_up(expr->len, BITS_PER_BYTE); + memset(ifname, 0, sizeof(ifname)); + mpz_export_data(ifname, expr->value, + BYTEORDER_HOST_ENDIAN, + ifname_len); + dev_array[i++] = xstrdup(ifname); if (i == dev_array_len) { dev_array_len *= 2; dev_array = xrealloc(dev_array, @@ -650,6 +658,10 @@ int mnl_nft_chain_add(struct netlink_ctx *ctx, struct cmd *cmd, nftnl_chain_set_data(nlc, NFTNL_CHAIN_DEVICES, dev_array, sizeof(char *) * dev_array_len); + i = 0; + while (dev_array[i] != NULL) + xfree(dev_array[i++]); + xfree(dev_array); } } @@ -1565,7 +1577,9 @@ int mnl_nft_flowtable_add(struct netlink_ctx *ctx, struct cmd *cmd, unsigned int flags) { struct nftnl_flowtable *flo; + unsigned int ifname_len; const char **dev_array; + char ifname[IFNAMSIZ]; struct nlmsghdr *nlh; int i = 0, len = 1; struct expr *expr; @@ -1586,13 +1600,24 @@ int mnl_nft_flowtable_add(struct netlink_ctx *ctx, struct cmd *cmd, list_for_each_entry(expr, &cmd->flowtable->dev_expr->expressions, list) len++; - dev_array = calloc(len, sizeof(char *)); - list_for_each_entry(expr, &cmd->flowtable->dev_expr->expressions, list) - dev_array[i++] = expr->identifier; + dev_array = xmalloc(sizeof(char *) * len); + + list_for_each_entry(expr, &cmd->flowtable->dev_expr->expressions, list) { + ifname_len = div_round_up(expr->len, BITS_PER_BYTE); + memset(ifname, 0, sizeof(ifname)); + mpz_export_data(ifname, expr->value, BYTEORDER_HOST_ENDIAN, + ifname_len); + dev_array[i++] = xstrdup(ifname); + } dev_array[i] = NULL; nftnl_flowtable_set_data(flo, NFTNL_FLOWTABLE_DEVICES, dev_array, sizeof(char *) * len); + + i = 0; + while (dev_array[i] != NULL) + xfree(dev_array[i++]); + free(dev_array); netlink_dump_flowtable(flo, ctx); diff --git a/src/parser_bison.y b/src/parser_bison.y index ad512cdb..fd00b40a 100644 --- a/src/parser_bison.y +++ b/src/parser_bison.y @@ -1909,9 +1909,9 @@ flowtable_list_expr : flowtable_expr_member flowtable_expr_member : STRING { - $$ = symbol_expr_alloc(&@$, SYMBOL_VALUE, - current_scope(state), - $1); + $$ = constant_expr_alloc(&@$, &string_type, + BYTEORDER_HOST_ENDIAN, + strlen($1) * BITS_PER_BYTE, $1); xfree($1); } ; |