From: Pavel Skripkin paskripkin@gmail.com
stable inclusion from stable-v5.10.90 commit 8d31cbab4c295d7010ebb729e9d02d0e9cece18f bugzilla: 186168 https://gitee.com/openeuler/kernel/issues/I4SHY1
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ 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 Signed-off-by: Chen Jun chenjun102@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- 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 f358120d59b3..dafad891998e 100644 --- a/drivers/i2c/i2c-dev.c +++ b/drivers/i2c/i2c-dev.c @@ -536,6 +536,9 @@ 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;