From 04315b072d623ba9200612a4c5f5330f1eb28a27 Mon Sep 17 00:00:00 2001 From: Michal Kubecek Date: Sun, 23 Aug 2020 21:40:24 +0200 Subject: [PATCH 05/17] ioctl: prevent argc underflow in do_perqueue() When first command line argument after "-Q" is "queue_mask", we parse the queue mask and following subcommand without checking if these arguments do actually exist. Add check if we have at least two arguments left after "queue_mask" in the corresponding branch. Fixes: 9ecd54248b1a ("ethtool: introduce new ioctl for per-queue settings") Signed-off-by: Michal Kubecek (cherry picked from commit 39c354e591b66cc29edaab89f90ed03a513ad88f) --- ethtool.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/ethtool.c b/ethtool.c index 4fa7a2c1716f..6c12452be7b4 100644 --- a/ethtool.c +++ b/ethtool.c @@ -5880,6 +5880,8 @@ static int do_perqueue(struct cmd_context *ctx) "The sub commands will be applied to all %d queues\n", n_queues); } else { + if (ctx->argc <= 2) + exit_bad_args(); ctx->argc--; ctx->argp++; if (parse_hex_u32_bitmap(*ctx->argp, MAX_NUM_QUEUE, -- 2.26.2