Commit-ID: 20c4d49c0f304f3f945bbd560b26afa98f75a0c4
Gitweb: http://git.kernel.org/tip/20c4d49c0f304f3f945bbd560b26afa98f75a0c4
Author: Dan Carpenter <dan.carpen...@oracle.com>
AuthorDate: Fri, 25 Aug 2017 15:14:09 +0300
Committer: Thomas Gleixner <t...@linutronix.de>
CommitDate: Fri, 25 Aug 2017 22:40:26 +0200
irqdomain: Prevent potential NULL pointer dereference in irq_domain_push_irq()
This code generates a Smatch warning:
kernel/irq/irqdomain.c:1511 irq_domain_push_irq()
warn: variable dereferenced before check 'root_irq_data' (see line 1508)
irq_get_irq_data() can return a NULL pointer, but the code dereferences
the returned pointer before checking it.
Move the NULL pointer check before the dereference.
[ tglx: Rewrote changelog to be precise and conforming to the instructions
in submitting-patches and added a Fixes tag. Sigh! ]
Fixes: 495c38d3001f ("irqdomain: Add irq_domain_{push,pop}_irq() functions")
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
Signed-off-by: Thomas Gleixner <t...@linutronix.de>
Acked-by: David Daney <david.da...@cavium.com>
Cc: Marc Zyngier <marc.zyng...@arm.com>
Cc: kernel-janit...@vger.kernel.org
Link: http://lkml.kernel.org/r/20170825121409.6rfv4vt6ztz2oqkt@mwanda
---
kernel/irq/irqdomain.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 1ff9912..d623517 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -1504,10 +1504,10 @@ int irq_domain_push_irq(struct irq_domain *domain, int
virq, void *arg)
if (WARN_ON(!irq_domain_is_hierarchy(domain)))
return -EINVAL;
- if (domain->parent != root_irq_data->domain)
+ if (!root_irq_data)
return -EINVAL;
- if (!root_irq_data)
+ if (domain->parent != root_irq_data->domain)
return -EINVAL;
child_irq_data = kzalloc_node(sizeof(*child_irq_data), GFP_KERNEL,
