Commit 860c3d03 authored by Dan Carpenter's avatar Dan Carpenter Committed by Martin K. Petersen
Browse files

scsi: scsi_debug: Fix some bugs in sdebug_error_write() 



There are two bug in this code:

 1) If count is zero, then it will lead to a NULL dereference.  The
    kmalloc() will successfully allocate zero bytes and the test for "if
    (buf[0] == '-')" will read beyond the end of the zero size buffer and
    Oops.

 2) The code does not ensure that the user's string is properly NUL
    terminated which could lead to a read overflow.

Fixes: a9996d72 ("scsi: scsi_debug: Add interface to manage error injection for a single device")
Signed-off-by: default avatarDan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/r/7733643d-e102-4581-8d29-769472011c97@moroto.mountain


Reviewed-by: default avatarWenchao Hao <haowenchao2@huawei.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 27900d71

drivers/scsi/scsi_debug.c

+1 −1
Original line number Diff line number Diff line
@@ -1019,7 +1019,7 @@ static ssize_t sdebug_error_write(struct file *file, const char __user *ubuf, 
	struct sdebug_err_inject *inject;

	struct scsi_device *sdev = (struct scsi_device *)file->f_inode->i_private;



	buf = kmalloc(count, GFP_KERNEL);

	buf = kzalloc(count + 1, GFP_KERNEL);

	if (!buf)

		return -ENOMEM;