[PATCH 0/3] fix error return code

These patches fix cases where the return code appears to be unintentially
nonnegative.

The complete semantic match that finds the problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier ret,l;
expression e1,e2,e3;
statement S;
@@

if (ret < 0)
 { ... return ret; }
... when != ret = e1
    when forall
(
 goto l;
|
 return ...;
|
 if (<+... ret = e3 ...+>) S
|
*if(...)
 {
  ... when != ret = e2
* return ret;
}
)
// </smpl>

From: Julia Lawall <redacted>

Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier ret;
expression e1,e2;
@@

if (ret < 0)
 { ... return ret; }
 ... when != ret = e1
     when forall
*if(...)
 {
  ... when != ret = e2
* return ret;
 }
// </smpl>

Signed-off-by: Julia Lawall <redacted>

---
 drivers/net/irda/ks959-sir.c    |    1 +
 drivers/net/irda/ksdazzle-sir.c |    1 +
 2 files changed, 2 insertions(+)

diff --git a/drivers/net/irda/ks959-sir.c b/drivers/net/irda/ks959-sir.c
index 824e2a9..5f3aeac 100644
--- a/drivers/net/irda/ks959-sir.c
+++ b/drivers/net/irda/ks959-sir.c

@@ -542,6 +542,7 @@ static int ks959_net_open(struct net_device *netdev)
 	sprintf(hwname, "usb#%d", kingsun->usbdev->devnum);
 	kingsun->irlap = irlap_open(netdev, &kingsun->qos, hwname);
 	if (!kingsun->irlap) {
+		err = -ENOMEM;
 		dev_err(&kingsun->usbdev->dev, "irlap_open failed\n");
 		goto free_mem;
 	}

diff --git a/drivers/net/irda/ksdazzle-sir.c b/drivers/net/irda/ksdazzle-sir.c
index 5a278ab..2d4b6a1 100644
--- a/drivers/net/irda/ksdazzle-sir.c
+++ b/drivers/net/irda/ksdazzle-sir.c

@@ -436,6 +436,7 @@ static int ksdazzle_net_open(struct net_device *netdev)
 	sprintf(hwname, "usb#%d", kingsun->usbdev->devnum);
 	kingsun->irlap = irlap_open(netdev, &kingsun->qos, hwname);
 	if (!kingsun->irlap) {
+		err = -ENOMEM;
 		dev_err(&kingsun->usbdev->dev, "irlap_open failed\n");
 		goto free_mem;
 	}

From: Julia Lawall <redacted>

Move up the initialization of rc so that failure of pci_alloc_consistent
returns -ENOMEM as well.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier ret;
expression e1,e2;
@@

if (ret < 0)
 { ... return ret; }
 ... when != ret = e1
     when forall
*if(...)
 {
  ... when != ret = e2
* return ret;
 }
// </smpl>

Signed-off-by: Julia Lawall <redacted>

---
 drivers/net/wan/dscc4.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wan/dscc4.c b/drivers/net/wan/dscc4.c
index 9eb6479..ef36caf 100644
--- a/drivers/net/wan/dscc4.c
+++ b/drivers/net/wan/dscc4.c

@@ -774,14 +774,15 @@ static int __devinit dscc4_init_one(struct pci_dev *pdev,
 	}
 	/* Global interrupt queue */
 	writel((u32)(((IRQ_RING_SIZE >> 5) - 1) << 20), ioaddr + IQLENR1);
+
+	rc = -ENOMEM;
+
 	priv->iqcfg = (__le32 *) pci_alloc_consistent(pdev,
 		IRQ_RING_SIZE*sizeof(__le32), &priv->iqcfg_dma);
 	if (!priv->iqcfg)
 		goto err_free_irq_5;
 	writel(priv->iqcfg_dma, ioaddr + IQCFG);
 
-	rc = -ENOMEM;
-
 	/*
 	 * SCC 0-3 private rx/tx irq structures
 	 * IQRX/TXi needs to be set soon. Learned it the hard way...

From: Julia Lawall <redacted>

Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
identifier ret;
expression e1,e2;
@@

if (ret < 0)
 { ... return ret; }
 ... when != ret = e1
     when forall
*if(...)
 {
  ... when != ret = e2
* return ret;
 }
// </smpl>

Signed-off-by: Julia Lawall <redacted>

---
 drivers/net/wimax/i2400m/fw.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wimax/i2400m/fw.c b/drivers/net/wimax/i2400m/fw.c
index 283237f..def12b3 100644
--- a/drivers/net/wimax/i2400m/fw.c
+++ b/drivers/net/wimax/i2400m/fw.c

@@ -326,8 +326,10 @@ int i2400m_barker_db_init(const char *_options)
 		unsigned barker;
 
 		options_orig = kstrdup(_options, GFP_KERNEL);
-		if (options_orig == NULL)
+		if (options_orig == NULL) {
+			result = -ENOMEM;
 			goto error_parse;
+		}
 		options = options_orig;
 
 		while ((token = strsep(&options, ",")) != NULL) {

From: Julia Lawall <redacted>
Date: Fri, 17 Aug 2012 09:46:55 +0200

These patches fix cases where the return code appears to be unintentially
nonnegative.

All applied, thanks Julia.