Re: [PATCH] IDE-TAPE NULL terminate strings.

Boris Petkov
2008-09-22T13:57:00Z

On Mon, Sep 22, 2008 at 3:16 PM, Sergei Shtylyov
<sshtylyov@ru.mvista.com> wrote:
> Hello.
>
> Mark de Wever wrote:
>
>> After updating my kernel to 2.6.26 the output for the ide-tape drive
>> during booting is garbled eg
>> ide-tape: hdd <-> ht0: Seagate <98>ß8A51|1À<81>Üº<98>ß STT20000A rev
>> 8A51|1À<81>Üº<98>ß
>
>> This patch fixes the problem by NULL terminating the strings.
>
> Looks like this bugs was introduced by this commit:
>
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commitdiff;h=41f81d545b6b1f585a02d1d8545978714f710e91

.. and I know why :). Those ide_tape_obj members (char fw_rev[6], vendor_id[10],
product_id[18]) were used only once in idetape_get_inquiry_results() so I moved
them there as local stack variables. Originally, they were kzalloc'ed as part of
struct ide_tape_obj and now they contain stack garbage therefore the funny
values. The simple solution would be to zero them out or:

Does the following patch help?

Signed-off-by: Borislav Petkov <petkovbb@gmail.com>

diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index 1bce84b..848d9df 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -2338,7 +2338,7 @@ static void
idetape_get_inquiry_results(ide_drive_t *drive)
{
idetape_tape_t *tape = drive->driver_data;
struct ide_atapi_pc pc;
- char fw_rev[6], vendor_id[10], product_id[18];
+ static char fw_rev[6], vendor_id[10], product_id[18];

idetape_create_inquiry_cmd(&pc);
if (idetape_queue_pc_tail(drive, &pc)) {

--
Regards/Gruss,
Boris