Hi All!
I think I've spotted a bug in the initialisation procedure in the loop driver,
@line 1027-1060, when there is allocation failure:
----BEGIN CODE----
loop_dev = kmalloc(max_loop * sizeof(struct loop_device), GFP_KERNEL);
if (!loop_dev)
return -ENOMEM;
loop_sizes = kmalloc(max_loop * sizeof(int), GFP_KERNEL);
if (!loop_sizes)
goto out_sizes;
loop_blksizes = kmalloc(max_loop * sizeof(int), GFP_KERNEL);
if (!loop_blksizes)
goto out_blksizes;
[...SNIP...]
out_sizes:
kfree(loop_dev);
out_blksizes:
kfree(loop_sizes);
----END CODE----
Two problems arise there:
1) Should allocation of loop_sizes fail, we'll try to free loop_sizes that
was NOT allocated (no problem because kfree does not free a NULL pointer).
But not very clean...
2) Should allocation of loop_blksizes fail, loop_dev will NOT be freed.
That one looks more problematic.
Am I wrong? Have I missed something? Anyway it's been there for ages, I
suppose.
Patch is very straigthforward, and is attached : swap the last 2 pairs of
lines, so that out_blksizes is before out_sizes, and kfree(loop_sizes is
before kfree(loop_dev).
Please CC: answers and comments as I'm no longer subscribed.
Cheers,
Yann.
-- .-----------------.--------------------.------------------.--------------------. | Yann E. MORIN | Real-Time Embedded | /"\ ASCII RIBBON | Erics' conspiracy: | | 0 662 376 056 | Software Designer | \ / CAMPAIGN | ___ | | --==< °_° >==-- °---.----------------: X AGAINST | \e/ There is no | | web: ymorin.free.fr | SETI@home 433 | / \ HTML MAIL | v conspiracy. | °---------------------°----------------°------------------°--------------------°--------------Boundary-00=_H7EC9IB1C70VXNCU5GUZ Content-Type: text/plain; charset="iso-8859-15"; name="loop.c.diff" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="loop.c.diff"
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