From 5e5919ad698c6edfd0c1bbbd47d97309c0cb7a83 Mon Sep 17 00:00:00 2001 From: Phil Sutter Date: Fri, 29 Nov 2024 12:01:39 +0100 Subject: [PATCH] xt: Fix translation error path JIRA: https://issues.redhat.com/browse/RHEL-5806 Upstream Status: nftables commit ce3d71348ee77d2d7ffa6a825afbc7471e92bc89 commit ce3d71348ee77d2d7ffa6a825afbc7471e92bc89 Author: Phil Sutter Date: Tue Mar 28 13:46:10 2023 +0200 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 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 31cf40e..6d5866d 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; -- 2.46.2