The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From a249cc8bc2e2fed680047d326eb9a50756724198 Mon Sep 17 00:00:00 2001

From: Aurelien Aptel aaptel@suse.com Date: Thu, 4 Mar 2021 17:42:21 +0000 Subject: [PATCH] cifs: fix credit accounting for extra channel

With multichannel, operations like the queries from "ls -lR" can cause all credits to be used and errors to be returned since max_credits was not being set correctly on the secondary channels and thus the client was requesting 0 credits incorrectly in some cases (which can lead to not having enough credits to perform any operation on that channel).

Signed-off-by: Aurelien Aptel aaptel@suse.com CC: stable@vger.kernel.org # v5.8+ Reviewed-by: Shyam Prasad N sprasad@microsoft.com Signed-off-by: Steve French stfrench@microsoft.com

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c index 112692300fb6..68642e3d4270 100644 --- a/fs/cifs/connect.c +++ b/fs/cifs/connect.c @@ -1429,6 +1429,11 @@ cifs_get_tcp_session(struct smb3_fs_context *ctx) tcp_ses->min_offload = ctx->min_offload; tcp_ses->tcpStatus = CifsNeedNegotiate;

+ if ((ctx->max_credits < 20) || (ctx->max_credits > 60000)) + tcp_ses->max_credits = SMB2_MAX_CREDITS_AVAILABLE; + else + tcp_ses->max_credits = ctx->max_credits; + tcp_ses->nr_targets = 1; tcp_ses->ignore_signature = ctx->ignore_signature; /* thread spawned, put it on the list */ @@ -2832,11 +2837,6 @@ static int mount_get_conns(struct smb3_fs_context *ctx, struct cifs_sb_info *cif

*nserver = server;

- if ((ctx->max_credits < 20) || (ctx->max_credits > 60000)) - server->max_credits = SMB2_MAX_CREDITS_AVAILABLE; - else - server->max_credits = ctx->max_credits; - /* get a reference to a SMB session */ ses = cifs_get_smb_ses(server, ctx); if (IS_ERR(ses)) { diff --git a/fs/cifs/sess.c b/fs/cifs/sess.c index 183a3a868d7b..63d517b9f2ff 100644 --- a/fs/cifs/sess.c +++ b/fs/cifs/sess.c @@ -230,6 +230,7 @@ cifs_ses_add_channel(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses, ctx.noautotune = ses->server->noautotune; ctx.sockopt_tcp_nodelay = ses->server->tcp_nodelay; ctx.echo_interval = ses->server->echo_interval / HZ; + ctx.max_credits = ses->server->max_credits;

/* * This will be used for encoding/decoding user/domain/pw