[PATCH] x86/mm: Fix cpumask_of_node() error condition
From: Peter Zijlstra <peterz@infradead.org>
Date: 2019-09-03 07:54:59
Also in:
linux-alpha, linux-mips, linux-s390, linux-sh, lkml, sparclinux
Subsystem:
the rest, x86 architecture (32-bit and 64-bit), x86 mm · Maintainers:
Linus Torvalds, Thomas Gleixner, Ingo Molnar, Borislav Petkov, Dave Hansen, Andy Lutomirski, Peter Zijlstra
On Mon, Sep 02, 2019 at 08:17:31PM +0200, Ingo Molnar wrote:
Nitpicking: please also fix the kernel message to say ">=".
Full patch below. --- Subject: x86/mm: Fix cpumask_of_node() error condition When CONFIG_DEBUG_PER_CPU_MAPS we validate that the @node argument of cpumask_of_node() is a valid node_id. It however forgets to check for negative numbers. Fix this by explicitly casting to unsigned. (unsigned)node >= nr_node_ids verifies: 0 <= node < nr_node_ids Also ammend the error message to match the condition. Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> --- arch/x86/mm/numa.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index e6dad600614c..4123100e0eaf 100644
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c@@ -861,9 +861,9 @@ void numa_remove_cpu(int cpu) */ const struct cpumask *cpumask_of_node(int node) { - if (node >= nr_node_ids) { + if ((unsigned)node >= nr_node_ids) { printk(KERN_WARNING - "cpumask_of_node(%d): node > nr_node_ids(%u)\n", + "cpumask_of_node(%d): (unsigned)node >= nr_node_ids(%u)\n", node, nr_node_ids); dump_stack(); return cpu_none_mask;