netdev - [PATCH net-next v2 3/3] netconsole: Populate dynamic entry even if netpoll fails

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240819103616.2260006-4-leitao@debian.org>
Date: Mon, 19 Aug 2024 03:36:13 -0700
From: Breno Leitao <leitao@...ian.org>
To: davem@...emloft.net,
	edumazet@...gle.com,
	kuba@...nel.org,
	pabeni@...hat.com
Cc: netdev@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Aijay Adams <aijay@...a.com>
Subject: [PATCH net-next v2 3/3] netconsole: Populate dynamic entry even if netpoll fails

Currently, netconsole discards targets that fail during initialization,
causing two issues:

1) Inconsistency between target list and configfs entries
  * user pass cmdline0, cmdline1. If cmdline0 fails, then cmdline1
    becomes cmdline0 in configfs.

2) Inability to manage failed targets from userspace
  * If user pass a target that fails with netpoll (interface not loaded at
    netcons initialization time, such as interface is a module), then
    the target will not exist in the configfs, so, user cannot re-enable
    or modify it from userspace.

Failed targets are now added to the target list and configfs, but
remain disabled until manually enabled or reconfigured. This change does
not change the behaviour if CONFIG_NETCONSOLE_DYNAMIC is not set.

CC: Aijay Adams <aijay@...a.com>
Signed-off-by: Breno Leitao <leitao@...ian.org>
---
 drivers/net/netconsole.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 9b5f605fe87a..82e178b34e4b 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -1260,11 +1260,18 @@ static struct netconsole_target *alloc_param_target(char *target_config,
 		goto fail;
 
 	err = netpoll_setup(&nt->np);
-	if (err)
-		goto fail;
+	if (!err) {
+		nt->enabled = true;
+	} else {
+		pr_err("Not enabling netconsole. Netpoll setup failed\n");
+		if (!IS_ENABLED(CONFIG_NETCONSOLE_DYNAMIC))
+			/* only fail if dynamic reconfiguration is set,
+			 * otherwise, keep the target in the list, but disabled.
+			 */
+			goto fail;
+	}
 
 	populate_configfs_item(nt, cmdline_count);
-	nt->enabled = true;
 
 	return nt;
 
-- 
2.43.5