Messages in this thread Patch in this message |  | | Date | Fri, 25 Aug 2017 13:43:39 -0700 | From | tip-bot for Dan Carpenter <> | Subject | [tip:irq/core] irqdomain: Prevent potential NULL pointer dereference in irq_domain_push_irq() |
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Commit-ID: 20c4d49c0f304f3f945bbd560b26afa98f75a0c4 Gitweb: http://git.kernel.org/tip/20c4d49c0f304f3f945bbd560b26afa98f75a0c4 Author: Dan Carpenter <dan.carpenter@oracle.com> AuthorDate: Fri, 25 Aug 2017 15:14:09 +0300 Committer: Thomas Gleixner <tglx@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.carpenter@oracle.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: David Daney <david.daney@cavium.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: kernel-janitors@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,
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