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New: ATA Passthrough generates incorrect LBA addresses with OS ASYNC activity, Image of Bus-trace attached

Bug 32362 [email protected] 1 participant 2 messages Mar 31, 2011 – May 12, 2012 SCSI

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https://bugzilla.kernel.org/show_bug.cgi?id=32362

Summary: ATA Passthrough generates incorrect LBA addresses with
OS ASYNC activity, Image of Bus-trace attached
Product: SCSI Drivers
Version: 2.5
Kernel Version: All
Platform: All
OS/Version: Linux
Tree: Mainline
Status: NEW
Severity: blocking
Priority: P1
Component: Other
AssignedTo: [email protected]
ReportedBy: [email protected]
Regression: No

Created an attachment (id=52792)
--> (https://bugzilla.kernel.org/attachment.cgi?id=52792)
Finisar Bus-Trace of SG tools w/System Activity

Bug: Low 28 bits of LBA address to drive after DMA completion (read/write), following the interrupt to the kernel, status is read from the drive with the updated LBA address. The 28 lower bits are then transposed into the NEXT drive commands upper 28bits.

Confirmed: smartmon/sgtools using a Finisar protocol analyzer.

When: Only occurs when using systems whos BIOS is set into Legacy (or ATA/IDE) modes. (Does NOT occur when using AHCI bios mode).

See attached image to see what occured when running SG tools to read the SMART log (command 0x2F)... It becomes very obvious that the ATA Pass-Through driver's actual data becomes over-written with the previous commands LBA address.

Example:

DMA-Write LBA=00000123456

    ->>  BUS:  Cmd 0x2f, LBA=0x0000123456

Read Status: DRDY, drive LBA=0x123457 (LBA updated in HW)

Device Identify LBA=0000000000

    ->>  BUS: Cmd 0xec, LBA=12345700000   <-- BAD/OOPS!!!

(In this case, CMD 0xec ignores LBA)..

However, a cleverly constructed packet could use a read/writes combined with a previously corrupted LBA address to access portions of the drive which should be considered 'restricted/confidential', thus compromising system security and potentially by-passing AV or other security products.

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#1 lore raw

[Bug 32362] ATA Passthrough generates incorrect LBA addresses with OS ASYNC activity, Image of Bus-trace attached

https://bugzilla.kernel.org/show_bug.cgi?id=32362

Alan <[email protected]> changed:

What |Removed |Added
----------------------------------------------------------------------------

                 CC|                            |[email protected]
          Component|Other                       |Serial ATA
         AssignedTo|scsi_drivers-other@kernel-b |[email protected]
                   |ugs.osdl.org                |
            Product|SCSI Drivers                |IO/Storage
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