sr_ioctl.c uses this pattern:
result = sr_do_ioctl(cd, &cgc);
to-user = buffer[];
kfree(buffer);
return result;
Use of a buffer without checking leaks information. Check result and jump
over the use of buffer if there is an error.
result = sr_do_ioctl(cd, &cgc);
if (result)
goto err;
to-user = buffer[];
err:
kfree(buffer);
return result;
Additionally, initialize the buffer to zero.
This problem can be seen in the 2.4.0 kernel.
Link: https://lore.kernel.org/r/20220411174756.2418435-1-trix@redhat.com
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>