Commit 9ccfca0f authored Mar 10, 2021 by Lv Yunlong Committed by Greg Kroah-Hartman Apr 07, 2021

scsi: st: Fix a use after free in st_open()

[ Upstream commit c8c165dea4c8f5ad67b1240861e4f6c5395fa4ac ]

In st_open(), if STp->in_use is true, STp will be freed by
scsi_tape_put(). However, STp is still used by DEBC_printk() after. It is
better to DEBC_printk() before scsi_tape_put().

Link: https://lore.kernel.org/r/20210311064636.10522-1-lyl2019@mail.ustc.edu.cn


Acked-by: Kai Mäkisara <kai.makisara@kolumbus.fi>
Signed-off-by: Lv Yunlong <lyl2019@mail.ustc.edu.cn>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

parent 97fe6ebe

drivers/scsi/st.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1267,8 +1267,8 @@ static int st_open(struct inode inode, struct file filp)
		spin_lock(&st_use_lock);
		if (STp->in_use) {
		spin_unlock(&st_use_lock);
		scsi_tape_put(STp);
		DEBC_printk(STp, "Device already in use.\n");
		scsi_tape_put(STp);
		return (-EBUSY);
		}