diff mbox series

[2/2] x86/PCI: Slightly simplify pirq_convert_irt_table()

Message ID 84bf047b01452a72642dbe355b02ef016c985a91.1683356951.git.christophe.jaillet@wanadoo.fr
State New
Headers
Series [1/2] x86/PCI: Fix a sanity check in pirq_convert_irt_table() |

Commit Message

Christophe JAILLET May 6, 2023, 7:11 a.m. UTC 
  'size' if computed twice. *ir and *it being the same, the result is the
same as well.

While at it, also use struct_size() which is less verbose, more robust and
more informative.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
 arch/x86/pci/irq.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Comments

Maciej W. Rozycki May 19, 2023, 11:24 a.m. UTC | #1 
On Sat, 6 May 2023, Christophe JAILLET wrote:

> 'size' if computed twice. *ir and *it being the same, the result is the
> same as well.

 There is no `it' data object in this function; I presume you meant `rt'. 
Then `*ir' and `*rt' are of a different type each, hence the calculations 
are not the same.  If they were the same, the function wouldn't be needed 
at all in the first place.  Therefore, NAK.

> While at it, also use struct_size() which is less verbose, more robust and
> more informative.

 This might be a valuable clean-up, thank you, please submit separately.

  Maciej
diff mbox series

Patch

diff --git a/arch/x86/pci/irq.c b/arch/x86/pci/irq.c
index e29b487cc069..6bc51f80eec2 100644
--- a/arch/x86/pci/irq.c
+++ b/arch/x86/pci/irq.c
@@ -140,14 +140,13 @@  static inline struct irq_routing_table *pirq_convert_irt_table(u8 *addr,
 	if (ir->signature != IRT_SIGNATURE || !ir->used || entries < ir->used)
 		return NULL;
 
-	size = sizeof(*ir) + ir->used * sizeof(ir->slots[0]);
+	size = struct_size(ir, slots, ir->used);
 	if (size > limit - addr)
 		return NULL;
 
 	DBG(KERN_DEBUG "PCI: $IRT Interrupt Routing Table found at 0x%lx\n",
 	    __pa(ir));
 
-	size = sizeof(*rt) + ir->used * sizeof(rt->slots[0]);
 	rt = kzalloc(size, GFP_KERNEL);
 	if (!rt)
 		return NULL;