releases/4.14.93/genirq-affinity-don-t-return-with-empty-affinity-masks-on-error.patch

   1 From 0211e12dd0a5385ecffd3557bc570dbad7fcf245 Mon Sep 17 00:00:00 2001
   2 From: Thomas Gleixner <tglx@linutronix.de>
   3 Date: Wed, 4 Apr 2018 12:40:07 +0200
   4 Subject: genirq/affinity: Don't return with empty affinity masks on error
   5
   6 From: Thomas Gleixner <tglx@linutronix.de>
   7
   8 commit 0211e12dd0a5385ecffd3557bc570dbad7fcf245 upstream.
   9
  10 When the allocation of node_to_possible_cpumask fails, then
  11 irq_create_affinity_masks() returns with a pointer to the empty affinity
  12 masks array, which will cause malfunction.
  13
  14 Reorder the allocations so the masks array allocation comes last and every
  15 failure path returns NULL.
  16
  17 Fixes: 9a0ef98e186d ("genirq/affinity: Assign vectors to all present CPUs")
  18 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
  19 Cc: Christoph Hellwig <hch@infradead.org>
  20 Cc: Ming Lei <ming.lei@redhat.com>
  21 Cc: Mihai Carabas <mihai.carabas@oracle.com>
  22 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  23
  24 ---
  25  kernel/irq/affinity.c |   15 ++++++++-------
  26  1 file changed, 8 insertions(+), 7 deletions(-)
  27
  28 --- a/kernel/irq/affinity.c
  29 +++ b/kernel/irq/affinity.c
  30 @@ -108,7 +108,7 @@ irq_create_affinity_masks(int nvecs, con
  31         int affv = nvecs - affd->pre_vectors - affd->post_vectors;
  32         int last_affv = affv + affd->pre_vectors;
  33         nodemask_t nodemsk = NODE_MASK_NONE;
  34 -       struct cpumask *masks;
  35 +       struct cpumask *masks = NULL;
  36         cpumask_var_t nmsk, *node_to_possible_cpumask;
  37
  38         /*
  39 @@ -121,13 +121,13 @@ irq_create_affinity_masks(int nvecs, con
  40         if (!zalloc_cpumask_var(&nmsk, GFP_KERNEL))
  41                 return NULL;
  42
  43 -       masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL);
  44 -       if (!masks)
  45 -               goto out;
  46 -
  47         node_to_possible_cpumask = alloc_node_to_possible_cpumask();
  48         if (!node_to_possible_cpumask)
  49 -               goto out;
  50 +               goto outcpumsk;
  51 +
  52 +       masks = kcalloc(nvecs, sizeof(*masks), GFP_KERNEL);
  53 +       if (!masks)
  54 +               goto outnodemsk;
  55
  56         /* Fill out vectors at the beginning that don't need affinity */
  57         for (curvec = 0; curvec < affd->pre_vectors; curvec++)
  58 @@ -192,8 +192,9 @@ done:
  59         /* Fill out vectors at the end that don't need affinity */
  60         for (; curvec < nvecs; curvec++)
  61                 cpumask_copy(masks + curvec, irq_default_affinity);
  62 +outnodemsk:
  63         free_node_to_possible_cpumask(node_to_possible_cpumask);
  64 -out:
  65 +outcpumsk:
  66         free_cpumask_var(nmsk);
  67         return masks;
  68  }