Apr 01 2011

[SCSI] bnx2fc: introduce missing kfree 

Author: Julia Lawall <julia@diku.dk>

Error handling code following a kmalloc should free the allocated data.

The semantic match that finds the problem is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// 
@r exists@
local idexpression x;
statement S;
expression E;
identifier f,f1,l;
position p1,p2;
expression *ptr != NULL;
@@

x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
<... when != x
     when != if (...) { <+...x...+> }
(
x->f1 = E
|
 (x->f1 == NULL || ...)
|
 f(...,x->f1,...)
)
...>
(
 return \(0\|<+...x...+>\|ptr\);
|
 return@p2 ...;
)

@script:python@
p1 << r.p1;
p2 << r.p2;
@@

print "* file: %s kmalloc %s return %s" % (p1[0].file,p1[0].line,p2[0].line)
// 

Signed-off-by: Julia Lawall 
Acked-by: Bhanu Prakash Gollapudi 
Signed-off-by: James Bottomley 

---
 drivers/scsi/bnx2fc/bnx2fc_hwi.c | 3 +++
 1 file changed, 3 insertions(+)
 
diff --git a/drivers/scsi/bnx2fc/bnx2fc_hwi.c b/drivers/scsi/bnx2fc/bnx2fc_hwi.c
index 1b680e2..f756d5f 100644
--- a/drivers/scsi/bnx2fc/bnx2fc_hwi.c
+++ b/drivers/scsi/bnx2fc/bnx2fc_hwi.c
@@ -522,6 +522,7 @@ void bnx2fc_process_l2_frame_compl(struct bnx2fc_rport *tgt,
 	fp = fc_frame_alloc(lport, payload_len);
 	if (!fp) {
 		printk(KERN_ERR PFX "fc_frame_alloc failure\n");
+		kfree(unsol_els);
 		return;
 	}
 
@@ -547,6 +548,7 @@ void bnx2fc_process_l2_frame_compl(struct bnx2fc_rport *tgt,
 				 */
 				printk(KERN_ERR PFX "dropping ELS 0x%x\n", op);
 				kfree_skb(skb);
+				kfree(unsol_els);
 				return;
 			}
 		}
@@ -563,6 +565,7 @@ void bnx2fc_process_l2_frame_compl(struct bnx2fc_rport *tgt,
 	} else {
 		BNX2FC_HBA_DBG(lport, "fh_r_ctl = 0x%x\n", fh->fh_r_ctl);
 		kfree_skb(skb);
+		kfree(unsol_els);
 	}
 }

qlambert