[PATCH AUTOSEL 5.3 24/89] nfs: Fix nfsi->nrequests count error on nfs_inode_remove_request

[PATCH AUTOSEL 5.3 24/89] nfs: Fix nfsi->nrequests count error on nfs_inode_remove_request

[Sasha Levin]

From: ZhangXiaoxu <zhangxiaoxu5@huawei.com>

[ Upstream commit 33ea5aaa87cdae0f9af4d6b7ee4f650a1a36fd1d ]

When xfstests testing, there are some WARNING as below:

WARNING: CPU: 0 PID: 6235 at fs/nfs/inode.c:122 nfs_clear_inode+0x9c/0xd8
Modules linked in:
CPU: 0 PID: 6235 Comm: umount.nfs
Hardware name: linux,dummy-virt (DT)
pstate: 60000005 (nZCv daif -PAN -UAO)
pc : nfs_clear_inode+0x9c/0xd8
lr : nfs_evict_inode+0x60/0x78
sp : fffffc000f68fc00
x29: fffffc000f68fc00 x28: fffffe00c53155c0
x27: fffffe00c5315000 x26: fffffc0009a63748
x25: fffffc000f68fd18 x24: fffffc000bfaaf40
x23: fffffc000936d3c0 x22: fffffe00c4ff5e20
x21: fffffc000bfaaf40 x20: fffffe00c4ff5d10
x19: fffffc000c056000 x18: 000000000000003c
x17: 0000000000000000 x16: 0000000000000000
x15: 0000000000000040 x14: 0000000000000228
x13: fffffc000c3a2000 x12: 0000000000000045
x11: 0000000000000000 x10: 0000000000000000
x9 : 0000000000000000 x8 : 0000000000000000
x7 : 0000000000000000 x6 : fffffc00084b027c
x5 : fffffc0009a64000 x4 : fffffe00c0e77400
x3 : fffffc000c0563a8 x2 : fffffffffffffffb
x1 : 000000000000764e x0 : 0000000000000001
Call trace:
 nfs_clear_inode+0x9c/0xd8
 nfs_evict_inode+0x60/0x78
 evict+0x108/0x380
 dispose_list+0x70/0xa0
 evict_inodes+0x194/0x210
 generic_shutdown_super+0xb0/0x220
 nfs_kill_super+0x40/0x88
 deactivate_locked_super+0xb4/0x120
 deactivate_super+0x144/0x160
 cleanup_mnt+0x98/0x148
 __cleanup_mnt+0x38/0x50
 task_work_run+0x114/0x160
 do_notify_resume+0x2f8/0x308
 work_pending+0x8/0x14

The nrequest should be increased/decreased only if PG_INODE_REF flag
was setted.

But in the nfs_inode_remove_request function, it maybe decrease when
no PG_INODE_REF flag, this maybe lead nrequests count error.

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nfs/write.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 85ca49549b39b..52cab65f91cf0 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -786,7 +786,6 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 	struct nfs_inode *nfsi = NFS_I(inode);
 	struct nfs_page *head;
 
-	atomic_long_dec(&nfsi->nrequests);
 	if (nfs_page_group_sync_on_bit(req, PG_REMOVE)) {
 		head = req->wb_head;
 
@@ -799,8 +798,10 @@ static void nfs_inode_remove_request(struct nfs_page *req)
 		spin_unlock(&mapping->private_lock);
 	}
 
-	if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags))
+	if (test_and_clear_bit(PG_INODE_REF, &req->wb_flags)) {
 		nfs_release_request(req);
+		atomic_long_dec(&nfsi->nrequests);
+	}
 }
 
 static void
-- 
2.20.1

[PATCH AUTOSEL 5.3 86/89] NFSv4: Fix leak of clp->cl_acceptor string

[Sasha Levin]

From: Chuck Lever <chuck.lever@oracle.com>

[ Upstream commit 1047ec868332034d1fbcb2fae19fe6d4cb869ff2 ]

Our client can issue multiple SETCLIENTID operations to the same
server in some circumstances. Ensure that calls to
nfs4_proc_setclientid() after the first one do not overwrite the
previously allocated cl_acceptor string.

unreferenced object 0xffff888461031800 (size 32):
  comm "mount.nfs", pid 2227, jiffies 4294822467 (age 1407.749s)
  hex dump (first 32 bytes):
    6e 66 73 40 6b 6c 69 6d 74 2e 69 62 2e 31 30 31  nfs@klimt.ib.101
    35 67 72 61 6e 67 65 72 2e 6e 65 74 00 00 00 00  5granger.net....
  backtrace:
    [<00000000ab820188>] __kmalloc+0x128/0x176
    [<00000000eeaf4ec8>] gss_stringify_acceptor+0xbd/0x1a7 [auth_rpcgss]
    [<00000000e85e3382>] nfs4_proc_setclientid+0x34e/0x46c [nfsv4]
    [<000000003d9cf1fa>] nfs40_discover_server_trunking+0x7a/0xed [nfsv4]
    [<00000000b81c3787>] nfs4_discover_server_trunking+0x81/0x244 [nfsv4]
    [<000000000801b55f>] nfs4_init_client+0x1b0/0x238 [nfsv4]
    [<00000000977daf7f>] nfs4_set_client+0xfe/0x14d [nfsv4]
    [<0000000053a68a2a>] nfs4_create_server+0x107/0x1db [nfsv4]
    [<0000000088262019>] nfs4_remote_mount+0x2c/0x59 [nfsv4]
    [<00000000e84a2fd0>] legacy_get_tree+0x2d/0x4c
    [<00000000797e947c>] vfs_get_tree+0x20/0xc7
    [<00000000ecabaaa8>] fc_mount+0xe/0x36
    [<00000000f15fafc2>] vfs_kern_mount+0x74/0x8d
    [<00000000a3ff4e26>] nfs_do_root_mount+0x8a/0xa3 [nfsv4]
    [<00000000d1c2b337>] nfs4_try_mount+0x58/0xad [nfsv4]
    [<000000004c9bddee>] nfs_fs_mount+0x820/0x869 [nfs]

Fixes: f11b2a1cfbf5 ("nfs4: copy acceptor name from context ... ")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nfs/nfs4proc.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c
index 1406858bae6c9..e1e7d2724b971 100644
--- a/fs/nfs/nfs4proc.c
+++ b/fs/nfs/nfs4proc.c
@@ -6058,6 +6058,7 @@ int nfs4_proc_setclientid(struct nfs_client *clp, u32 program,
 	}
 	status = task->tk_status;
 	if (setclientid.sc_cred) {
+		kfree(clp->cl_acceptor);
 		clp->cl_acceptor = rpcauth_stringify_acceptor(setclientid.sc_cred);
 		put_rpccred(setclientid.sc_cred);
 	}
-- 
2.20.1

[PATCH AUTOSEL 5.3 87/89] SUNRPC: fix race to sk_err after xs_error_report

[Sasha Levin]

From: Benjamin Coddington <bcodding@redhat.com>

[ Upstream commit af84537dbd1b39505d1f3d8023029b4a59666513 ]

Since commit 4f8943f80883 ("SUNRPC: Replace direct task wakeups from
softirq context") there has been a race to the value of the sk_err if both
XPRT_SOCK_WAKE_ERROR and XPRT_SOCK_WAKE_DISCONNECT are set.  In that case,
we may end up losing the sk_err value that existed when xs_error_report was
called.

Fix this by reverting to the previous behavior: instead of using SO_ERROR
to retrieve the value at a later time (which might also return sk_err_soft),
copy the sk_err value onto struct sock_xprt, and use that value to wake
pending tasks.

Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: 4f8943f80883 ("SUNRPC: Replace direct task wakeups from softirq context")
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 include/linux/sunrpc/xprtsock.h |  1 +
 net/sunrpc/xprtsock.c           | 17 ++++++++---------
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/include/linux/sunrpc/xprtsock.h b/include/linux/sunrpc/xprtsock.h
index 7638dbe7bc500..a940de03808dd 100644
--- a/include/linux/sunrpc/xprtsock.h
+++ b/include/linux/sunrpc/xprtsock.h
@@ -61,6 +61,7 @@ struct sock_xprt {
 	struct mutex		recv_mutex;
 	struct sockaddr_storage	srcaddr;
 	unsigned short		srcport;
+	int			xprt_err;
 
 	/*
 	 * UDP socket buffer size parameters
diff --git a/net/sunrpc/xprtsock.c b/net/sunrpc/xprtsock.c
index e2176c167a579..4e0b5bed6c737 100644
--- a/net/sunrpc/xprtsock.c
+++ b/net/sunrpc/xprtsock.c
@@ -1243,19 +1243,21 @@ static void xs_error_report(struct sock *sk)
 {
 	struct sock_xprt *transport;
 	struct rpc_xprt *xprt;
-	int err;
 
 	read_lock_bh(&sk->sk_callback_lock);
 	if (!(xprt = xprt_from_sock(sk)))
 		goto out;
 
 	transport = container_of(xprt, struct sock_xprt, xprt);
-	err = -sk->sk_err;
-	if (err == 0)
+	transport->xprt_err = -sk->sk_err;
+	if (transport->xprt_err == 0)
 		goto out;
 	dprintk("RPC:       xs_error_report client %p, error=%d...\n",
-			xprt, -err);
-	trace_rpc_socket_error(xprt, sk->sk_socket, err);
+			xprt, -transport->xprt_err);
+	trace_rpc_socket_error(xprt, sk->sk_socket, transport->xprt_err);
+
+	/* barrier ensures xprt_err is set before XPRT_SOCK_WAKE_ERROR */
+	smp_mb__before_atomic();
 	xs_run_error_worker(transport, XPRT_SOCK_WAKE_ERROR);
  out:
 	read_unlock_bh(&sk->sk_callback_lock);
@@ -2470,7 +2472,6 @@ static void xs_wake_write(struct sock_xprt *transport)
 static void xs_wake_error(struct sock_xprt *transport)
 {
 	int sockerr;
-	int sockerr_len = sizeof(sockerr);
 
 	if (!test_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
 		return;
@@ -2479,9 +2480,7 @@ static void xs_wake_error(struct sock_xprt *transport)
 		goto out;
 	if (!test_and_clear_bit(XPRT_SOCK_WAKE_ERROR, &transport->sock_state))
 		goto out;
-	if (kernel_getsockopt(transport->sock, SOL_SOCKET, SO_ERROR,
-				(char *)&sockerr, &sockerr_len) != 0)
-		goto out;
+	sockerr = xchg(&transport->xprt_err, 0);
 	if (sockerr < 0)
 		xprt_wake_pending_tasks(&transport->xprt, sockerr);
 out:
-- 
2.20.1