From 2aa10d26b6f0aa47334e45990892b66c3278d227 Mon Sep 17 00:00:00 2001 From: Kuniyuki Iwashima Date: Wed, 2 Apr 2025 13:26:47 -0700 Subject: [PATCH] Revert "smb: client: Fix netns refcount imbalance causing leaks and use-after-free" commit c707193a17128fae2802d10cbad7239cc57f0c95 upstream. This reverts commit 4e7f1644f2ac6d01dc584f6301c3b1d5aac4eaef. The commit e9f2517a3e18 ("smb: client: fix TCP timers deadlock after rmmod") is not only a bogus fix for LOCKDEP null-ptr-deref but also introduces a real issue, TCP sockets leak, which will be explained in detail in the next revert. Also, CNA assigned CVE-2024-54680 to it but is rejecting it. [0] Thus, we are reverting the commit and its follow-up commit 4e7f1644f2ac ("smb: client: Fix netns refcount imbalance causing leaks and use-after-free"). Link: https://lore.kernel.org/all/2025040248-tummy-smilingly-4240@gregkh/ #[0] Fixes: 4e7f1644f2ac ("smb: client: Fix netns refcount imbalance causing leaks and use-after-free") Signed-off-by: Kuniyuki Iwashima Cc: stable@vger.kernel.org Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/smb/client/connect.c | 16 ++++++++-------- 1 file changed, 8 insertions(+), 8 deletions(-) diff --git a/fs/smb/client/connect.c b/fs/smb/client/connect.c index 3aaf5cdce1b7..e1c5496d1866 100644 --- a/fs/smb/client/connect.c +++ b/fs/smb/client/connect.c @@ -316,7 +316,6 @@ cifs_abort_connection(struct TCP_Server_Info *server) server->ssocket->flags); sock_release(server->ssocket); server->ssocket = NULL; - put_net(cifs_net_ns(server)); } server->sequence_number = 0; server->session_estab = false; @@ -3142,12 +3141,8 @@ generic_ip_connect(struct TCP_Server_Info *server) /* * Grab netns reference for the socket. * - * This reference will be released in several situations: - * - In the failure path before the cifsd thread is started. - * - In the all place where server->socket is released, it is - * also set to NULL. - * - Ultimately in clean_demultiplex_info(), during the final - * teardown. + * It'll be released here, on error, or in clean_demultiplex_info() upon server + * teardown. */ get_net(net); @@ -3163,8 +3158,10 @@ generic_ip_connect(struct TCP_Server_Info *server) } rc = bind_socket(server); - if (rc < 0) + if (rc < 0) { + put_net(cifs_net_ns(server)); return rc; + } /* * Eventually check for other socket options to change from @@ -3210,6 +3207,9 @@ generic_ip_connect(struct TCP_Server_Info *server) if (sport == htons(RFC1001_PORT)) rc = ip_rfc1001_connect(server); + if (rc < 0) + put_net(cifs_net_ns(server)); + return rc; }