kernel/linux.git/drivers/block/drbd, branch v4.14.286

drbd: remove usage of list iterator variable after loop

2022-05-25T06:41:18+00:00

[ Upstream commit 901aeda62efa21f2eae937bccb71b49ae531be06 ] In preparation to limit the scope of a list iterator to the list traversal loop, use a dedicated pointer to iterate through the list [1]. Since that variable should not be used past the loop iteration, a separate variable is used to 'remember the current location within the loop'. To either continue iterating from that position or skip the iteration (if the previous iteration was complete) list_prepare_entry() is used. Link: https://lore.kernel.org/all/CAHk-=wgRr_D8CB-D9Kg-c=EHreAsk5SqXPwr9Y7k9sA6cWXJ6w@mail.gmail.com/ [1] Signed-off-by: Jakob Koschel Link: https://lore.kernel.org/r/20220331220349.885126-1-jakobkoschel@gmail.com Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

block: drbd: drbd_nl: Make conversion to 'enum drbd_ret_code' explicit

2022-05-15T17:40:26+00:00

commit 1f1e87b4dc4598eac57a69868534b92d65e47e82 upstream. Fixes the following W=1 kernel build warning(s): from drivers/block/drbd/drbd_nl.c:24: drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_set_role’: drivers/block/drbd/drbd_nl.c:793:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion] drivers/block/drbd/drbd_nl.c:795:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion] drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_attach’: drivers/block/drbd/drbd_nl.c:1965:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion] drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_connect’: drivers/block/drbd/drbd_nl.c:2690:10: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion] drivers/block/drbd/drbd_nl.c: In function ‘drbd_adm_disconnect’: drivers/block/drbd/drbd_nl.c:2803:11: warning: implicit conversion from ‘enum drbd_state_rv’ to ‘enum drbd_ret_code’ [-Wenum-conversion] Cc: Philipp Reisner Cc: Lars Ellenberg Cc: Jens Axboe Cc: drbd-dev@lists.linbit.com Cc: linux-block@vger.kernel.org Signed-off-by: Lee Jones Link: https://lore.kernel.org/r/20210312105530.2219008-8-lee.jones@linaro.org Signed-off-by: Jens Axboe Cc: Nathan Chancellor Signed-off-by: Greg Kroah-Hartman

drbd: Fix five use after free bugs in get_initial_state

2022-04-20T07:08:29+00:00

[ Upstream commit aadb22ba2f656581b2f733deb3a467c48cc618f6 ] In get_initial_state, it calls notify_initial_state_done(skb,..) if cb->args[5]==1. If genlmsg_put() failed in notify_initial_state_done(), the skb will be freed by nlmsg_free(skb). Then get_initial_state will goto out and the freed skb will be used by return value skb->len, which is a uaf bug. What's worse, the same problem goes even further: skb can also be freed in the notify_*_state_change -> notify_*_state calls below. Thus 4 additional uaf bugs happened. My patch lets the problem callee functions: notify_initial_state_done and notify_*_state_change return an error code if errors happen. So that the error codes could be propagated and the uaf bugs can be avoid. v2 reports a compilation warning. This v3 fixed this warning and built successfully in my local environment with no additional warnings. v2: https://lore.kernel.org/patchwork/patch/1435218/ Fixes: a29728463b254 ("drbd: Backport the "events2" command") Signed-off-by: Lv Yunlong Reviewed-by: Christoph Böhmwalder Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

drbd: fix potential silent data corruption

2022-04-20T07:08:11+00:00

commit f4329d1f848ac35757d9cc5487669d19dfc5979c upstream. Scenario: --------- bio chain generated by blk_queue_split(). Some split bio fails and propagates its error status to the "parent" bio. But then the (last part of the) parent bio itself completes without error. We would clobber the already recorded error status with BLK_STS_OK, causing silent data corruption. Reproducer: ----------- How to trigger this in the real world within seconds: DRBD on top of degraded parity raid, small stripe_cache_size, large read_ahead setting. Drop page cache (sysctl vm.drop_caches=1, fadvise "DONTNEED", umount and mount again, "reboot"). Cause significant read ahead. Large read ahead request is split by blk_queue_split(). Parts of the read ahead that are already in the stripe cache, or find an available stripe cache to use, can be serviced. Parts of the read ahead that would need "too much work", would need to wait for a "stripe_head" to become available, are rejected immediately. For larger read ahead requests that are split in many pieces, it is very likely that some "splits" will be serviced, but then the stripe cache is exhausted/busy, and the remaining ones will be rejected. Signed-off-by: Lars Ellenberg Signed-off-by: Christoph Böhmwalder Cc: # 4.13.x Link: https://lore.kernel.org/r/20220330185551.3553196-1-christoph.boehmwalder@linbit.com Signed-off-by: Jens Axboe Signed-off-by: Greg Kroah-Hartman

signal: Allow cifs and drbd to receive their terminating signals

2020-01-27T13:46:43+00:00

[ Upstream commit 33da8e7c814f77310250bb54a9db36a44c5de784 ] My recent to change to only use force_sig for a synchronous events wound up breaking signal reception cifs and drbd. I had overlooked the fact that by default kthreads start out with all signals set to SIG_IGN. So a change I thought was safe turned out to have made it impossible for those kernel thread to catch their signals. Reverting the work on force_sig is a bad idea because what the code was doing was very much a misuse of force_sig. As the way force_sig ultimately allowed the signal to happen was to change the signal handler to SIG_DFL. Which after the first signal will allow userspace to send signals to these kernel threads. At least for wake_ack_receiver in drbd that does not appear actively wrong. So correct this problem by adding allow_kernel_signal that will allow signals whose siginfo reports they were sent by the kernel through, but will not allow userspace generated signals, and update cifs and drbd to call allow_kernel_signal in an appropriate place so that their thread can receive this signal. Fixing things this way ensures that userspace won't be able to send signals and cause problems, that it is clear which signals the threads are expecting to receive, and it guarantees that nothing else in the system will be affected. This change was partly inspired by similar cifs and drbd patches that added allow_signal. Reported-by: ronnie sahlberg Reported-by: Christoph Böhmwalder Tested-by: Christoph Böhmwalder Cc: Steve French Cc: Philipp Reisner Cc: David Laight Fixes: 247bc9470b1e ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes") Fixes: 72abe3bcf091 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig") Fixes: fee109901f39 ("signal/drbd: Use send_sig not force_sig") Fixes: 3cf5d076fb4d ("signal: Remove task parameter from force_sig") Signed-off-by: "Eric W. Biederman" Signed-off-by: Sasha Levin

drbd: Change drbd_request_detach_interruptible's return type to int

2019-12-17T19:39:55+00:00

[ Upstream commit 5816a0932b4fd74257b8cc5785bc8067186a8723 ] Clang warns when an implicit conversion is done between enumerated types: drivers/block/drbd/drbd_state.c:708:8: warning: implicit conversion from enumeration type 'enum drbd_ret_code' to different enumeration type 'enum drbd_state_rv' [-Wenum-conversion] rv = ERR_INTR; ~ ^~~~~~~~ drbd_request_detach_interruptible's only call site is in the return statement of adm_detach, which returns an int. Change the return type of drbd_request_detach_interruptible to match, silencing Clang's warning. Reported-by: Nick Desaulniers Reviewed-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

drbd: fix print_st_err()'s prototype to match the definition

2019-12-05T14:37:45+00:00

[ Upstream commit 2c38f035117331eb78d0504843c79ea7c7fabf37 ] print_st_err() is defined with its 4th argument taking an 'enum drbd_state_rv' but its prototype use an int for it. Fix this by using 'enum drbd_state_rv' in the prototype too. Signed-off-by: Luc Van Oostenryck Signed-off-by: Roland Kammerer Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

drbd: do not block when adjusting "disk-options" while IO is frozen

2019-12-05T14:37:45+00:00

[ Upstream commit f708bd08ecbdc23d03aaedf5b3311ebe44cfdb50 ] "suspending" IO is overloaded. It can mean "do not allow new requests" (obviously), but it also may mean "must not complete pending IO", for example while the fencing handlers do their arbitration. When adjusting disk options, we suspend io (disallow new requests), then wait for the activity-log to become unused (drain all IO completions), and possibly replace it with a new activity log of different size. If the other "suspend IO" aspect is active, pending IO completions won't happen, and we would block forever (unkillable drbdsetup process). Fix this by skipping the activity log adjustment if the "al-extents" setting did not change. Also, in case it did change, fail early without blocking if it looks like we would block forever. Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

drbd: reject attach of unsuitable uuids even if connected

2019-12-05T14:37:44+00:00

[ Upstream commit fe43ed97bba3b11521abd934b83ed93143470e4f ] Multiple failure scenario: a) all good Connected Primary/Secondary UpToDate/UpToDate b) lose disk on Primary, Connected Primary/Secondary Diskless/UpToDate c) continue to write to the device, changes only make it to the Secondary storage. d) lose disk on Secondary, Connected Primary/Secondary Diskless/Diskless e) now try to re-attach on Primary This would have succeeded before, even though that is clearly the wrong data set to attach to (missing the modifications from c). Because we only compared our "effective" and the "to-be-attached" data generation uuid tags if (device->state.conn < C_CONNECTED). Fix: change that constraint to (device->state.pdsk != D_UP_TO_DATE) compare the uuids, and reject the attach. This patch also tries to improve the reverse scenario: first lose Secondary, then Primary disk, then try to attach the disk on Secondary. Before this patch, the attach on the Secondary succeeds, but since commit drbd: disconnect, if the wrong UUIDs are attached on a connected peer the Primary will notice unsuitable data, and drop the connection hard. Though unfortunately at a point in time during the handshake where we cannot easily abort the attach on the peer without more refactoring of the handshake. We now reject any attach to "unsuitable" uuids, as long as we can see a Primary role, unless we already have access to "good" data. Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin

drbd: ignore "all zero" peer volume sizes in handshake

2019-12-05T14:37:44+00:00

[ Upstream commit 94c43a13b8d6e3e0dd77b3536b5e04a84936b762 ] During handshake, if we are diskless ourselves, we used to accept any size presented by the peer. Which could be zero if that peer was just brought up and connected to us without having a disk attached first, in which case both peers would just "flip" their volume sizes. Now, even a diskless node will ignore "zero" sizes presented by a diskless peer. Also a currently Diskless Primary will refuse to shrink during handshake: it may be frozen, and waiting for a "suitable" local disk or peer to re-appear (on-no-data-accessible suspend-io). If the peer is smaller than what we used to be, it is not suitable. The logic for a diskless node during handshake is now supposed to be: believe the peer, if - I don't have a current size myself - we agree on the size anyways - I do have a current size, am Secondary, and he has the only disk - I do have a current size, am Primary, and he has the only disk, which is larger than my current size Signed-off-by: Lars Ellenberg Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin