Re: [REGRESSION 6.1.70] system calls with CIFS mounts failing with "Resource temporarily unavailable"

From: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
To: "Mohamed Abuelfotoh, Hazem" <abuehaze@amazon.com>,
	"pc@manguebit.com" <pc@manguebit.com>
Cc: "gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
	"leonardo@schenkel.net" <leonardo@schenkel.net>,
	"linux-cifs@vger.kernel.org" <linux-cifs@vger.kernel.org>,
	"m.weissbach@info-gate.de" <m.weissbach@info-gate.de>,
	"regressions@lists.linux.dev" <regressions@lists.linux.dev>,
	"sairon@sairon.cz" <sairon@sairon.cz>,
	"stable@vger.kernel.org" <stable@vger.kernel.org>,
	Shyam Prasad N <nspmangalore@gmail.com>,
	Darren Kenny <darren.kenny@oracle.com>,
	Ramanan Govindarajan <ramanan.govindarajan@oracle.com>,
	Vegard Nossum <vegard.nossum@oracle.com>,
	david.flynn@oracle.com
Subject: Re: [REGRESSION 6.1.70] system calls with CIFS mounts failing with "Resource temporarily unavailable"
Date: Tue, 16 Jan 2024 15:53:22 +0530	[thread overview]
Message-ID: <09738f0f-53a2-43f1-a09d-a2bef48e1344@oracle.com> (raw)
In-Reply-To: <53F11617-D406-47C6-8CA7-5BE26EB042BE@amazon.com>

Hi,

On 15/01/24 7:52 pm, Mohamed Abuelfotoh, Hazem wrote:
> It looks like both 5.15.146 and 5.10.206 are impacted by this regression as they both have the
> bad commit 33eae65c6f (smb: client: fix OOB in SMB2_query_info_init()). We tried to
> apply the proposed fix eb3e28c1e89b ("smb3: Replace smb2pdu 1-element
> arrays with flex-arrays”) but there are a lot of dependencies required to do the backport.
> Is it possible to consider the simple fix that Paulo proposed as a solution for 5.10 and 5.15.
> We were lucky with 5.4 as it doesn’t have the bad commit because of merge conflict reported
> in https://lore.kernel.org/all/2023122857-doubling-crazed-27f4@gregkh/T/#m3aa009c332999268f71361237ace6ded9110f0d0
> 

I think we are also seeing the same error on running xfstests with cifs.

[root@vm xfstests-dev]# ./check -g quick -s smb3
TEST_DEV=//<SERVER_IP>/TEST is mounted but not a type cifs filesystem

This is with 5.15.147 stable kernel.

I started seeing this since 5.15.146 and on bisection it points to the 
same commit:

commit bfd18c0f570e ("smb: client: fix OOB in SMB2_query_info_init()"), 
reverting that commit fixed the issue and also when I applied the below 
diff provided in this thread, the tests run fine.

[root@vm xfstests-dev]# ./check -g quick -s smb3 cifs/001
SECTION       -- smb3
FSTYP         -- cifs
PLATFORM      -- Linux/x86_64 vm 5.15.147-master.el9.v5.x86_64 #1 SMP 
Mon Jan 15 22:39:33 PST 2024
MKFS_OPTIONS  -- //<SERVER_IP>/SCRATCH
MOUNT_OPTIONS -- 
-ousername=root,password=PASSWORD,noperm,mfsymlinks,actimeo=0 
//<SERVER_IP>/SCRATCH /mnt/scratch

cifs/001 1s ...  1s
generic/001 16s ...

Thanks,
Harshit

> diff --git a/fs/smb/client/smb2pdu.c b/fs/smb/client/smb2pdu.c
> 	index 05ff8a457a3d..aed5067661de 100644
> 	--- a/fs/smb/client/smb2pdu.c
> 	+++ b/fs/smb/client/smb2pdu.c
> 	@@ -3556,7 +3556,7 @@ SMB2_query_info_init(struct cifs_tcon *tcon, struct TCP_Server_Info *server,
> 	
> 	 	iov[0].iov_base = (char *)req;
> 	 	/* 1 for Buffer */
> 	-	iov[0].iov_len = len;
> 	+	iov[0].iov_len = len - 1;
> 	 	return 0;
> 	 }
> 
> Hazem