[PATCH nft] libnftables: fix crash when freeing non-malloc'd address

[Florian Westphal <fw@strlen.de>]

dirname may return static pointer:
munmap_chunk(): invalid pointer
20508 Aborted  nft -f test

Fixes: 6ef04f99382c ("libnftables: search for default include path last")
Signed-off-by: Florian Westphal <fw@strlen.de>
---
 src/libnftables.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/libnftables.c b/src/libnftables.c
index af4734c05004..586f8fdede76 100644
--- a/src/libnftables.c
+++ b/src/libnftables.c
@@ -789,12 +789,12 @@ static int nft_run_optimized_file(struct nft_ctx *nft, const char *filename)
 static int nft_ctx_add_basedir_include_path(struct nft_ctx *nft,
 					    const char *filename)
 {
-	const char *basedir = dirname(xstrdup(filename));
+	char *basedir = xstrdup(filename);
 	int ret;
 
-	ret = nft_ctx_add_include_path(nft, basedir);
+	ret = nft_ctx_add_include_path(nft, dirname(basedir));
 
-	free_const(basedir);
+	free(basedir);
 
 	return ret;
 }
-- 
2.44.2