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From:   Peilin Ye <yepeilin.cs@gmail.com>
To:     Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc:     Peilin Ye <yepeilin.cs@gmail.com>,
        Dan Carpenter <dan.carpenter@oracle.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel-mentees@lists.linuxfoundation.org,
        linux1394-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org
Subject: [Linux-kernel-mentees] [PATCH v2] firewire: Prevent kernel-infoleak in ioctl_get_info()
Date:   Mon, 27 Jul 2020 11:45:21 -0400
Message-Id: <20200727154521.315774-1-yepeilin.cs@gmail.com>
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ioctl_get_info() is copying uninitialized stack memory to userspace due to
the compiler not initializing holes in statically allocated structures.
Fix it by initializing `event` using memset() in fill_bus_reset_event().

Cc: stable@vger.kernel.org
Fixes: 344bbc4de14e ("firewire: Generalize get_config_rom to get_info.")
Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peilin Ye <yepeilin.cs@gmail.com>
---
Change in v2:
    - Add an appropriate `Fixes` tag. (Suggested by Arnd Bergmann
      <arnd@arndb.de>)

 drivers/firewire/core-cdev.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/firewire/core-cdev.c b/drivers/firewire/core-cdev.c
index fb6c651214f3..2341d762df5b 100644
--- a/drivers/firewire/core-cdev.c
+++ b/drivers/firewire/core-cdev.c
@@ -340,6 +340,8 @@ static void fill_bus_reset_event(struct fw_cdev_event_bus_reset *event,
 {
 	struct fw_card *card = client->device->card;
 
+	memset(event, 0, sizeof(*event));
+
 	spin_lock_irq(&card->lock);
 
 	event->closure	     = client->bus_reset_closure;
-- 
2.25.1