queue-4.4/nfc-fix-potential-null-pointer-deref-in-nfc_genl_dump_ses_done.patch

   1 From 4cd8371a234d051f9c9557fcbb1f8c523b1c0d10 Mon Sep 17 00:00:00 2001
   2 From: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
   3 Date: Thu, 9 Dec 2021 09:13:07 +0100
   4 Subject: nfc: fix potential NULL pointer deref in nfc_genl_dump_ses_done
   5
   6 From: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
   7
   8 commit 4cd8371a234d051f9c9557fcbb1f8c523b1c0d10 upstream.
   9
  10 The done() netlink callback nfc_genl_dump_ses_done() should check if
  11 received argument is non-NULL, because its allocation could fail earlier
  12 in dumpit() (nfc_genl_dump_ses()).
  13
  14 Fixes: ac22ac466a65 ("NFC: Add a GET_SE netlink API")
  15 Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
  16 Link: https://lore.kernel.org/r/20211209081307.57337-1-krzysztof.kozlowski@canonical.com
  17 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
  18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  19 ---
  20  net/nfc/netlink.c |    6 ++++--
  21  1 file changed, 4 insertions(+), 2 deletions(-)
  22
  23 --- a/net/nfc/netlink.c
  24 +++ b/net/nfc/netlink.c
  25 @@ -1366,8 +1366,10 @@ static int nfc_genl_dump_ses_done(struct
  26  {
  27         struct class_dev_iter *iter = (struct class_dev_iter *) cb->args[0];
  28
  29 -       nfc_device_iter_exit(iter);
  30 -       kfree(iter);
  31 +       if (iter) {
  32 +               nfc_device_iter_exit(iter);
  33 +               kfree(iter);
  34 +       }
  35
  36         return 0;
  37  }