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authorMike Travis <travis@sgi.com>2009-01-11 06:58:09 +0100
committerIngo Molnar <mingo@elte.hu>2009-01-11 19:13:02 +0100
commit802bf931f2688ad125b73db597ce63cc842fb27a (patch)
treee3715fce62ffeaac7f06f352dc538dccac215216 /kernel/irq
parentcpumask: convert other misc kernel functions (diff)
downloadlinux-802bf931f2688ad125b73db597ce63cc842fb27a.tar.xz
linux-802bf931f2688ad125b73db597ce63cc842fb27a.zip
cpumask: fix bug in use cpumask_var_t in irq_desc
Impact: fix bug where new irq_desc uses old cpumask pointers which are freed. As Yinghai pointed out, init_copy_one_irq_desc() copies the old desc to the new desc overwriting the cpumask pointers. Since the old_desc and the cpumask pointers are freed, then memory corruption will occur if these old pointers are used. Move the allocation of these pointers to after the copy. Signed-off-by: Mike Travis <travis@sgi.com> Cc: Yinghai Lu <yinghai@kernel.org>
Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/handle.c8
-rw-r--r--kernel/irq/numa_migrate.c13
2 files changed, 9 insertions, 12 deletions
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
index b8fa1354f01c..f01c0a30cb42 100644
--- a/kernel/irq/handle.c
+++ b/kernel/irq/handle.c
@@ -85,8 +85,6 @@ void init_kstat_irqs(struct irq_desc *desc, int cpu, int nr)
static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
{
- int node = cpu_to_node(cpu);
-
memcpy(desc, &irq_desc_init, sizeof(struct irq_desc));
spin_lock_init(&desc->lock);
@@ -100,7 +98,7 @@ static void init_one_irq_desc(int irq, struct irq_desc *desc, int cpu)
printk(KERN_ERR "can not alloc kstat_irqs\n");
BUG_ON(1);
}
- if (!init_alloc_desc_masks(desc, node, false)) {
+ if (!init_alloc_desc_masks(desc, cpu, false)) {
printk(KERN_ERR "can not alloc irq_desc cpumasks\n");
BUG_ON(1);
}
@@ -188,10 +186,6 @@ struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
printk(KERN_ERR "can not alloc irq_desc\n");
BUG_ON(1);
}
- if (!init_alloc_desc_masks(desc, node, false)) {
- printk(KERN_ERR "can not alloc irq_desc cpumasks\n");
- BUG_ON(1);
- }
init_one_irq_desc(irq, desc, cpu);
irq_desc_ptrs[irq] = desc;
diff --git a/kernel/irq/numa_migrate.c b/kernel/irq/numa_migrate.c
index f001a4ea6414..666260e4c065 100644
--- a/kernel/irq/numa_migrate.c
+++ b/kernel/irq/numa_migrate.c
@@ -38,16 +38,22 @@ static void free_kstat_irqs(struct irq_desc *old_desc, struct irq_desc *desc)
old_desc->kstat_irqs = NULL;
}
-static void init_copy_one_irq_desc(int irq, struct irq_desc *old_desc,
+static bool init_copy_one_irq_desc(int irq, struct irq_desc *old_desc,
struct irq_desc *desc, int cpu)
{
memcpy(desc, old_desc, sizeof(struct irq_desc));
+ if (!init_alloc_desc_masks(desc, cpu, false)) {
+ printk(KERN_ERR "irq %d: can not get new irq_desc cpumask "
+ "for migration.\n", irq);
+ return false;
+ }
spin_lock_init(&desc->lock);
desc->cpu = cpu;
lockdep_set_class(&desc->lock, &irq_desc_lock_class);
init_copy_kstat_irqs(old_desc, desc, cpu, nr_cpu_ids);
init_copy_desc_masks(old_desc, desc);
arch_init_copy_chip_data(old_desc, desc, cpu);
+ return true;
}
static void free_one_irq_desc(struct irq_desc *old_desc, struct irq_desc *desc)
@@ -83,15 +89,12 @@ static struct irq_desc *__real_move_irq_desc(struct irq_desc *old_desc,
desc = old_desc;
goto out_unlock;
}
- if (!init_alloc_desc_masks(desc, node, false)) {
- printk(KERN_ERR "irq %d: can not get new irq_desc cpumask "
- "for migration.\n", irq);
+ if (!init_copy_one_irq_desc(irq, old_desc, desc, cpu)) {
/* still use old one */
kfree(desc);
desc = old_desc;
goto out_unlock;
}
- init_copy_one_irq_desc(irq, old_desc, desc, cpu);
irq_desc_ptrs[irq] = desc;