lkml.org 
[lkml]   [2022]   [Jan]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.19 17/27] i2c: validate user data in compat ioctl
Date
From: Pavel Skripkin <paskripkin@gmail.com>

[ Upstream commit bb436283e25aaf1533ce061605d23a9564447bdf ]

Wrong user data may cause warning in i2c_transfer(), ex: zero msgs.
Userspace should not be able to trigger warnings, so this patch adds
validation checks for user data in compact ioctl to prevent reported
warnings

Reported-and-tested-by: syzbot+e417648b303855b91d8a@syzkaller.appspotmail.com
Fixes: 7d5cb45655f2 ("i2c compat ioctls: move to ->compat_ioctl()")
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/i2c/i2c-dev.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/i2c/i2c-dev.c b/drivers/i2c/i2c-dev.c
index 57aece8098416..140dd074fdee5 100644
--- a/drivers/i2c/i2c-dev.c
+++ b/drivers/i2c/i2c-dev.c
@@ -544,6 +544,9 @@ static long compat_i2cdev_ioctl(struct file *file, unsigned int cmd, unsigned lo
sizeof(rdwr_arg)))
return -EFAULT;

+ if (!rdwr_arg.msgs || rdwr_arg.nmsgs == 0)
+ return -EINVAL;
+
if (rdwr_arg.nmsgs > I2C_RDWR_IOCTL_MAX_MSGS)
return -EINVAL;

--
2.34.1


\
 
 \ /
  Last update: 2022-01-03 15:26    [W:0.127 / U:0.144 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site