linux_dsm_epyc7002/include
Mikulas Patocka fd7c092e71 dm: fix truncated status strings
Avoid returning a truncated table or status string instead of setting
the DM_BUFFER_FULL_FLAG when the last target of a table fills the
buffer.

When processing a table or status request, the function retrieve_status
calls ti->type->status. If ti->type->status returns non-zero,
retrieve_status assumes that the buffer overflowed and sets
DM_BUFFER_FULL_FLAG.

However, targets don't return non-zero values from their status method
on overflow. Most targets returns always zero.

If a buffer overflow happens in a target that is not the last in the
table, it gets noticed during the next iteration of the loop in
retrieve_status; but if a buffer overflow happens in the last target, it
goes unnoticed and erroneously truncated data is returned.

In the current code, the targets behave in the following way:
* dm-crypt returns -ENOMEM if there is not enough space to store the
  key, but it returns 0 on all other overflows.
* dm-thin returns errors from the status method if a disk error happened.
  This is incorrect because retrieve_status doesn't check the error
  code, it assumes that all non-zero values mean buffer overflow.
* all the other targets always return 0.

This patch changes the ti->type->status function to return void (because
most targets don't use the return code). Overflow is detected in
retrieve_status: if the status method fills up the remaining space
completely, it is assumed that buffer overflow happened.

Cc: stable@vger.kernel.org
Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-01 22:45:44 +00:00
..
acpi PCI changes for the v3.9 merge window: 2013-02-25 21:18:18 -08:00
asm-generic Merge branch 'next' of git://git.monstr.eu/linux-2.6-microblaze 2013-02-26 19:50:22 -08:00
clocksource arm: arch_timer: add missing inline in stub function 2013-02-11 15:16:05 -08:00
crypto
drm drm: Add HDMI infoframe helpers 2013-02-22 08:20:10 +01:00
keys
linux dm: fix truncated status strings 2013-03-01 22:45:44 +00:00
math-emu
media [media] media: ov7670: Add possibility to disable pixclk during hblank 2013-02-08 14:35:06 -02:00
memory
misc
net hlist: drop the node parameter from iterators 2013-02-27 19:10:24 -08:00
pcmcia
ras
rdma IB/core: Add "type 2" memory windows support 2013-02-21 11:51:45 -08:00
rxrpc
scsi
sound ASoC: Final updates for v3.9 2013-02-16 15:48:48 +01:00
target target: Rename spc_get_write_same_sectors -> sbc_get_write_same_sectors 2013-02-23 12:46:14 -08:00
trace Merge branch 'for-3.9/core' of git://git.kernel.dk/linux-block 2013-02-28 12:52:24 -08:00
uapi nbd: support FLUSH requests 2013-02-27 19:10:22 -08:00
video Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2013-02-25 16:46:44 -08:00
xen xen: event channel arrays are xen_ulong_t and not unsigned long 2013-02-20 08:45:07 -05:00
Kbuild