From ce3d71348ee77d2d7ffa6a825afbc7471e92bc89 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Tue, 28 Mar 2023 13:46:10 +0200 Subject: xt: Fix translation error path If xtables support was compiled in but the required libxtables DSO is not found, nft prints an error message and leaks memory: | counter packets 0 bytes 0 XT target MASQUERADE not found This is not as bad as it seems, the output combines stdout and stderr. Dropping stderr produces an incomplete ruleset listing, though. While this seemingly inline output can't easily be avoided, fix a few things: * Respect octx->error_fp, libnftables might have been configured to redirect stderr somewhere else. * Align error message formatting with others. * Don't return immediately, but free allocated memory and fall back to printing the expression in "untranslated" form. Fixes: 5c30feeee5cfe ("xt: Delay libxtables access until translation") Signed-off-by: Phil Sutter --- src/xt.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/src/xt.c b/src/xt.c index f63096a5..b17aafd5 100644 --- a/src/xt.c +++ b/src/xt.c @@ -56,9 +56,10 @@ void xt_stmt_xlate(const struct stmt *stmt, struct output_ctx *octx) case NFT_XT_MATCH: mt = xtables_find_match(stmt->xt.name, XTF_TRY_LOAD, NULL); if (!mt) { - fprintf(stderr, "XT match %s not found\n", + fprintf(octx->error_fp, + "# Warning: XT match %s not found\n", stmt->xt.name); - return; + break; } size = XT_ALIGN(sizeof(*m)) + stmt->xt.infolen; @@ -83,9 +84,10 @@ void xt_stmt_xlate(const struct stmt *stmt, struct output_ctx *octx) case NFT_XT_TARGET: tg = xtables_find_target(stmt->xt.name, XTF_TRY_LOAD); if (!tg) { - fprintf(stderr, "XT target %s not found\n", + fprintf(octx->error_fp, + "# Warning: XT target %s not found\n", stmt->xt.name); - return; + break; } size = XT_ALIGN(sizeof(*t)) + stmt->xt.infolen; -- cgit v1.2.3