linux/drivers/block/drbd
Lars Ellenberg 001a88687a drbd: fix potential data corruption and protocol error
We assumed only bios with bi_idx == 0 would end up
in drbd_make_request().

That is wrong.

At least device mapper, in __clone_and_map(), may submit
clones only covering a partial bio, but sharing
the original bvec, by adjusting bi_idx and relevant
other bio members of the clone.

We used __bio_for_each_segment() in various places,
even though that is documented as
 * drivers should not use the __ version unless they _really_ want to
 * run through the entire bio and not just pending pieces

Impact: we would send the full bio bvec, even for the clone
with bi_idx > 0, which will cause data corruption on the
peer (because we submit wrong data at the clone offset),
and will cause a DRBD protocol error, disconnect/reconnect
and resync (thus fixing the corruption),
because the next package header would be expected right
in the middle of the sent data, causing DRBD magic mismatch.

Fix: drop the assert, and use bio_for_each_segment()
instead of the __ version.

Conflicts:

	drbd/drbd_tracing.c

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
2012-05-09 15:16:39 +02:00
..
drbd_actlog.c drbd: Consider the disk-timeout also for meta-data IO operations 2012-05-09 15:16:30 +02:00
drbd_bitmap.c drbd: Consider the disk-timeout also for meta-data IO operations 2012-05-09 15:16:30 +02:00
drbd_int.h drbd: Consider the disk-timeout also for meta-data IO operations 2012-05-09 15:16:30 +02:00
drbd_main.c drbd: fix potential data corruption and protocol error 2012-05-09 15:16:39 +02:00
drbd_nl.c drbd: send intermediate state change results to the peer 2012-05-09 15:15:56 +02:00
drbd_proc.c drbd: cosmetic: fix accidental division instead of modulo when pretty printing 2012-05-09 10:01:39 +02:00
drbd_receiver.c drbd: Fix a potential write ordering issue on SyncTarget nodes 2012-05-09 15:16:38 +02:00
drbd_req.c drbd: fix potential data corruption and protocol error 2012-05-09 15:16:39 +02:00
drbd_req.h drbd: Immediately allow completion of IOs, that wait for IO completions on a failed disk 2012-05-09 10:16:04 +02:00
drbd_strings.c drbd: Rename enum drbd_state_ret_codes to enum drbd_state_rv 2011-03-10 11:36:18 +01:00
drbd_vli.h Fix common misspellings 2011-03-31 11:26:23 -03:00
drbd_worker.c drbd: fix potential data corruption and protocol error 2012-05-09 15:16:39 +02:00
drbd_wrappers.h drbd: Get rid of unnecessary macros (2) 2011-03-10 11:36:15 +01:00
Kconfig drbd: Kconfig fix 2009-12-29 17:38:28 +01:00
Makefile drbd: remove tracing bits 2009-10-01 21:17:58 +02:00