This is a note to let you know that I've just added the patch titled
smb3: do not attempt multichannel to server which does not support it
to the 5.11-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
smb3-do-not-attempt-multichannel-to-server-which-does-not-support-it.patch
and it can be found in the queue-5.11 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 9c2dc11df50d1c8537075ff6b98472198e24438e Mon Sep 17 00:00:00 2001
From: Steve French <stfrench@xxxxxxxxxxxxx>
Date: Fri, 7 May 2021 20:00:41 -0500
Subject: smb3: do not attempt multichannel to server which does not support it
From: Steve French <stfrench@xxxxxxxxxxxxx>
commit 9c2dc11df50d1c8537075ff6b98472198e24438e upstream.
We were ignoring CAP_MULTI_CHANNEL in the server response - if the
server doesn't support multichannel we should not be attempting it.
See MS-SMB2 section 3.2.5.2
Reviewed-by: Shyam Prasad N <sprasad@xxxxxxxxxxxxx>
Reviewed-By: Tom Talpey <tom@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v5.8+
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/cifs/sess.c | 6 ++++++
1 file changed, 6 insertions(+)
--- a/fs/cifs/sess.c
+++ b/fs/cifs/sess.c
@@ -97,6 +97,12 @@ int cifs_try_adding_channels(struct cifs
return 0;
}
+ if (!(ses->server->capabilities & SMB2_GLOBAL_CAP_MULTI_CHANNEL)) {
+ cifs_dbg(VFS, "server %s does not support multichannel\n", ses->server->hostname);
+ ses->chan_max = 1;
+ return 0;
+ }
+
/*
* Make a copy of the iface list at the time and use that
* instead so as to not hold the iface spinlock for opening
Patches currently in stable-queue which might be from stfrench@xxxxxxxxxxxxx are
queue-5.11/cifs-fix-regression-when-mounting-shares-with-prefix-paths.patch
queue-5.11/smb2-fix-use-after-free-in-smb2_ioctl_query_info.patch
queue-5.11/cifs-fix-leak-in-cifs_smb3_do_mount-ctx.patch
queue-5.11/cifs-return-correct-error-code-from-smb2_get_enc_key.patch
queue-5.11/cifs-detect-dead-connections-only-when-echoes-are-enabled.patch
queue-5.11/cifs-fix-out-of-bound-memory-access-when-calling-smb3_notify-at-mount-point.patch
queue-5.11/smb3-if-max_channels-set-to-more-than-one-channel-request-multichannel.patch
queue-5.11/smb3-do-not-attempt-multichannel-to-server-which-does-not-support-it.patch
queue-5.11/smb3-when-mounting-with-multichannel-include-it-in-requested-capabilities.patch
