[PATCH 0/6] fix error return code

[PATCH 0/6] fix error return code

[Julia Lawall]

The complate semantic patch that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@ok exists@
identifier f,ret,i;
expression e;
constant c;
@@

// identify a function that returns a negative return value at least once.
f(...) {
... when any
(
return -c@i;
|
ret = -c@i;
... when != ret = e
return ret;
|
if (ret < 0) { ... return ret; }
)
... when any
}

@r exists@
identifier ret,ok.f,fn;
expression e1,e2,e3,e4,e5,e6,x;
statement S,S1;
position p1,p2,p3;
@@

// identify a case where the return variable is set to a non-negative value
// and then returned in error-handling code
f(...) {
... when any
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != \(ret = e1\|ret++\|ret--\|ret+=e1\|ret-=e1\)
    when != &ret
    when any
(
 if (<+... ret = e5 ...+>) S1
|
 if (<+... &ret ...+>) S1
|
if@p2(<+...x = fn(...)...+>)
 {
  ... when != ret = e6
      when forall
 return@p3 ret;
}
|
break;
|
x = fn(...)
... when != \(ret = e4\|ret++\|ret--\|ret+=e4\|ret-=e4\)
    when != &ret
(
 if (<+... ret = e3 ...+>) S
|
 if (<+... &ret ...+>) S
|
if@p2(<+...\(x != 0\|x < 0\|x == NULL\|IS_ERR(x)\)...+>)
 {
  ... when != ret = e2
      when forall
 return@p3 ret;
}
)
)
... when any
}

@printer depends on r@
position p;
identifier ok.f,pr;
constant char [] c;
@@

f(...) { <...pr@p(...,c,...)...> }

@bad0 exists@
identifier r.ret,ok.f,g != {ERR_PTR,IS_ERR};
position p != printer.p;
@@

f(...) { ... when any
g@p(...,ret,...)
... when any
 }

@bad depends on !bad0 exists@
position r.p1,r.p2;
statement S1,S2;
identifier r.ret;
expression e1;
@@

// ignore the above if there is some path where the variable is set to
// something else
(
if@p1 (\(ret < 0\|ret != 0\)) S1
|
ret@p1 = 0
)
... when any
 \(ret = e1\|ret++\|ret--\|ret+=e1\|ret-=e1\|&ret\)
... when any
if@p2(...) S2

@bad1 depends on !bad0 && !bad exists@
position r.p2;
statement S2;
identifier r.ret;
expression e1;
constant c;
@@

ret = -c
... when != \(ret = e1\|ret++\|ret--\|ret+=e1\|ret-=e1\)
    when != &ret
    when any
if@p2(...) S2

@bad2 depends on !bad0 && !bad && !bad1 exists@
position r.p1,r.p2;
identifier r.ret;
expression e1;
statement S2;
constant c;
@@

// likewise ignore it if there has been an intervening return
ret@p1 = 0
... when != if (...) { ... ret = e1 ... return ret; }
    when != if (...) { ... return -c; }
    when any
if@p2(...) S2


@script:python depends on !bad0 && !bad && !bad1 && !bad2@
p1 << r.p1;
p2 << r.p2;
p3 << r.p3;
@@

cocci.print_main("",p1)
cocci.print_secs("",p2)
cocci.print_secs("",p3)

// </smpl>

[PATCH 1/6] NFC: pn533: fix error return code

[Julia Lawall]

From: Julia Lawall <Julia.Lawall@lip6.fr>

Return a negative error code on failure.

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

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
The error code is chosen according to the other call to this function
in the same file.

 drivers/nfc/pn533.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/nfc/pn533.c b/drivers/nfc/pn533.c
index d46a700..a859303 100644
--- a/drivers/nfc/pn533.c
+++ b/drivers/nfc/pn533.c
@@ -2554,8 +2554,10 @@ static int pn533_data_exchange_complete(struct pn533 *dev, void *_arg,
 	}
 
 	skb = pn533_build_response(dev);
-	if (!skb)
+	if (!skb) {
+		rc = -EIO;
 		goto error;
+	}
 
 	arg->cb(arg->cb_context, skb, 0);
 	kfree(arg);

[PATCH 2/6] i7core_edac: fix error return code

[Julia Lawall]

From: Julia Lawall <Julia.Lawall@lip6.fr>

Return a negative error code on failure.

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

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/edac/i7core_edac.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/edac/i7core_edac.c b/drivers/edac/i7core_edac.c
index 9cd0b30..5da90de 100644
--- a/drivers/edac/i7core_edac.c
+++ b/drivers/edac/i7core_edac.c
@@ -1177,7 +1177,7 @@ static int i7core_create_sysfs_devices(struct mem_ctl_info *mci)
 
 	pvt->addrmatch_dev = kzalloc(sizeof(*pvt->addrmatch_dev), GFP_KERNEL);
 	if (!pvt->addrmatch_dev)
-		return rc;
+		return -ENOMEM;
 
 	pvt->addrmatch_dev->type = &addrmatch_type;
 	pvt->addrmatch_dev->bus = mci->dev.bus;
@@ -1198,7 +1198,7 @@ static int i7core_create_sysfs_devices(struct mem_ctl_info *mci)
 		if (!pvt->chancounts_dev) {
 			put_device(pvt->addrmatch_dev);
 			device_del(pvt->addrmatch_dev);
-			return rc;
+			return -ENOMEM;
 		}
 
 		pvt->chancounts_dev->type = &all_channel_counts_type;

[PATCH 3/6] HSI: nokia-modem: fix error return code

[Julia Lawall]

From: Julia Lawall <Julia.Lawall@lip6.fr>

Return a negative error code on failure.

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

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/hsi/clients/nokia-modem.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/hsi/clients/nokia-modem.c b/drivers/hsi/clients/nokia-modem.c
index f0c2145..e07009a 100644
--- a/drivers/hsi/clients/nokia-modem.c
+++ b/drivers/hsi/clients/nokia-modem.c
@@ -199,6 +199,7 @@ static int nokia_modem_probe(struct device *dev)
 	modem->ssi_protocol = hsi_new_client(port, &ssip);
 	if (!modem->ssi_protocol) {
 		dev_err(dev, "Could not register ssi-protocol device\n");
+		err = -ENOMEM;
 		goto error2;
 	}
 

[PATCH 4/6] solos-pci: fix error return code

[Julia Lawall]

From: Julia Lawall <Julia.Lawall@lip6.fr>

Return a negative error code on failure.

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

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/atm/solos-pci.c |    2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/atm/solos-pci.c b/drivers/atm/solos-pci.c
index 7652e8d..21b0bc6 100644
--- a/drivers/atm/solos-pci.c
+++ b/drivers/atm/solos-pci.c
@@ -1225,11 +1225,13 @@ static int fpga_probe(struct pci_dev *dev, const struct pci_device_id *id)
 	card->config_regs = pci_iomap(dev, 0, CONFIG_RAM_SIZE);
 	if (!card->config_regs) {
 		dev_warn(&dev->dev, "Failed to ioremap config registers\n");
+		err = -ENOMEM;
 		goto out_release_regions;
 	}
 	card->buffers = pci_iomap(dev, 1, DATA_RAM_SIZE);
 	if (!card->buffers) {
 		dev_warn(&dev->dev, "Failed to ioremap data buffers\n");
+		err = -ENOMEM;
 		goto out_unmap_config;
 	}
 

[PATCH 5/6] ib_srpt: fix error return code

[Julia Lawall]

From: Julia Lawall <Julia.Lawall@lip6.fr>

Return a negative error code on failure.

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

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/infiniband/ulp/srpt/ib_srpt.c |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/infiniband/ulp/srpt/ib_srpt.c b/drivers/infiniband/ulp/srpt/ib_srpt.c
index 7206547..cbfdce7 100644
--- a/drivers/infiniband/ulp/srpt/ib_srpt.c
+++ b/drivers/infiniband/ulp/srpt/ib_srpt.c
@@ -2135,8 +2135,8 @@ static int srpt_create_ch_ib(struct srpt_rdma_ch *ch)
 
 	ch->thread = kthread_run(srpt_compl_thread, ch, "ib_srpt_compl");
 	if (IS_ERR(ch->thread)) {
-		printk(KERN_ERR "failed to create kernel thread %ld\n",
-		       PTR_ERR(ch->thread));
+		ret = PTR_ERR(ch->thread);
+		printk(KERN_ERR "failed to create kernel thread %ld\n", ret);
 		ch->thread = NULL;
 		goto err_destroy_qp;
 	}
@@ -2580,6 +2580,7 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 	if (!nacl) {
 		printk(KERN_INFO "Rejected login because no ACL has been"
 		       " configured yet for initiator %s.\n", ch->sess_name);
+		ret = -EINVAL;
 		rej->reason = __constant_cpu_to_be32(
 				SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED);
 		goto destroy_ib;
@@ -2590,6 +2591,7 @@ static int srpt_cm_req_recv(struct ib_cm_id *cm_id,
 		rej->reason = __constant_cpu_to_be32(
 				SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES);
 		pr_debug("Failed to create session\n");
+		ret = PTR_ERR(ch->sess);
 		goto deregister_session;
 	}
 	ch->sess->se_node_acl = &nacl->nacl;

[PATCH 6/6] dmaengine: ste_dma40: fix error return code

[Julia Lawall]

From: Julia Lawall <Julia.Lawall@lip6.fr>

Return a negative error code on failure.

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

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

---
 drivers/dma/ste_dma40.c |    1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/dma/ste_dma40.c b/drivers/dma/ste_dma40.c
index 7de218c..c62d26b 100644
--- a/drivers/dma/ste_dma40.c
+++ b/drivers/dma/ste_dma40.c
@@ -3432,6 +3432,7 @@ static int __init d40_lcla_allocate(struct d40_base *base)
 
 			d40_err(base->dev, "Failed to allocate %d pages.\n",
 				base->lcla_pool.pages);
+			ret = -ENOMEM;
 
 			for (j = 0; j < i; j++)
 				free_pages(page_list[j], base->lcla_pool.pages);

Re: [PATCH 4/6] solos-pci: fix error return code

[David Miller]

From: Julia Lawall <Julia.Lawall@lip6.fr>
Date: Sat, 22 Nov 2014 15:39:17 +0100

> From: Julia Lawall <Julia.Lawall@lip6.fr>
> 
> Return a negative error code on failure.
> 
> A simplified version of the semantic match that finds this problem is as
> follows: (http://coccinelle.lip6.fr/)
 ...
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Applied, thanks Julia.

Re: [PATCH 5/6] ib_srpt: fix error return code

[Bart Van Assche]

On 11/22/14 15:39, Julia Lawall wrote:
> Return a negative error code on failure.

Reviewed-by: Bart Van Assche <bvanassche@acm.org>

Re: [PATCH 6/6] dmaengine: ste_dma40: fix error return code

[Linus Walleij]

On Sat, Nov 22, 2014 at 3:39 PM, Julia Lawall <Julia.Lawall@lip6.fr> wrote:

> From: Julia Lawall <Julia.Lawall@lip6.fr>
>
> Return a negative error code on failure.
>
> 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 (\(ret < 0\|ret != 0\))
>  { ... return ret; }
> |
> ret = 0
> )
> ... when != ret = e1
>     when != &ret
> *if(...)
> {
>   ... when != ret = e2
>       when forall
>  return ret;
> }
> // </smpl>
>
> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>

Acked-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij

[PATCH 0/6] fix error return code

[Julia Lawall]

These patches fix cases where the return code appears to be unintentially 0.

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

// <smpl>
@r@
identifier f;
expression ret,e;
constant C;
@@

f(...) { <+...
(
return -C;
|
ret = -C
... when != ret = e
return ret;
|
if (ret < 0) { ... return ret; }
)
...+> }

@s@
identifier r.f,ret;
@@

f(...) { <+... return ret; ...+> }

@@
identifier r.f,s.ret;
expression e,e1,e2,e3,e4,x;
@@

f(...) { <+...
(
if (\(ret != 0\|ret < 0\) || ...) { ... return ...; }
|
ret = 0
)
... when != ret = e1
*x = \(kmalloc\|kzalloc\|kcalloc\|devm_kzalloc\|ioremap\|ioremap_nocache\|devm_ioremap\|devm_ioremap_nocache\)(...);
... when != x = e2
    when != ret = e3
*if (x == NULL || ...)
{
  ... when != ret = e4
*  return ret;
}
...+> }
// </smpl>