Commit 0b3e7388 authored by Julia Lawall's avatar Julia Lawall Committed by Jesse Barnes
Browse files

PCI: introduce missing kfree

Error handling code following a kmalloc should free the allocated data.
Since the subsequent code that could provoke an error does not use the
allocated data, the allocation is just moved below it.

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

)

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

(
if ((x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...)) == NULL) S
|
x@p1 = \(kmalloc\|kzalloc\|kcalloc\)(...);
...
if (x == NULL) S
)
<... when != x
     when != if (...) { <+...x...+> }
x->f = E
...>
(
 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)
// </smpl>

Signed-off-by: default avatarJulia Lawall <julia@diku.dk>
Reviewed-by: default avatarMatthew Wilcox <willy@linux.intel.com>
Reviewed-by: default avatarKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: default avatarJesse Barnes <jbarnes@virtuousgeek.org>
parent 1c35b8e5
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+3 −2
Original line number Diff line number Diff line
@@ -79,14 +79,15 @@ static int __init dummy_probe(struct pcie_device *dev)
	struct slot *slot, *tmp;
	struct pci_dev *pdev = dev->port;
	struct pci_bus *pbus = pdev->subordinate;
	if (!(slot = kzalloc(sizeof(*slot), GFP_KERNEL)))
		return -ENOMEM;
	/* Note: pciehp_detect_mode != PCIEHP_DETECT_ACPI here */
	if (pciehp_get_hp_hw_control_from_firmware(pdev))
		return -ENODEV;
	if (!(pos = pci_find_capability(pdev, PCI_CAP_ID_EXP)))
		return -ENODEV;
	pci_read_config_dword(pdev, pos + PCI_EXP_SLTCAP, &slot_cap);
	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
	if (!slot)
		return -ENOMEM;
	slot->number = slot_cap >> 19;
	list_for_each_entry(tmp, &dummy_slots, slot_list) {
		if (tmp->number == slot->number)