From 2c24b5b1487646f68960f25e13a1b0df645d4f49 Mon Sep 17 00:00:00 2001 From: Tom Caputi Date: Tue, 1 May 2018 14:24:20 -0400 Subject: [PATCH] Fix issues found with zfs diff Two deadlocks / ASSERT failures were introduced in a2c2ed1b which would occur whenever arc_buf_fill() failed to decrypt a block of data. This occurred because the call to arc_buf_destroy() which was responsible for cleaning up the newly created buffer would attempt to take out the hdr lock that it was already holding. This was resolved by calling the underlying functions directly without retaking the lock. In addition, the dmu_diff() code did not properly ensure that keys were loaded and mapped before begining dataset traversal. It turns out that this code does not need to look at any encrypted values, so the code was altered to perform raw IO only. Reviewed by: Matthew Ahrens Reviewed-by: Brian Behlendorf Signed-off-by: Tom Caputi Closes #7354 Closes #7456 --- module/zfs/arc.c | 13 +++-- module/zfs/dmu_diff.c | 18 +++++-- tests/runfiles/linux.run | 2 +- .../functional/cli_root/zfs_diff/Makefile.am | 1 + .../cli_root/zfs_diff/zfs_diff_encrypted.ksh | 53 +++++++++++++++++++ 5 files changed, 80 insertions(+), 7 deletions(-) create mode 100755 tests/zfs-tests/tests/functional/cli_root/zfs_diff/zfs_diff_encrypted.ksh diff --git a/module/zfs/arc.c b/module/zfs/arc.c index 040e94365..fa7f62d99 100644 --- a/module/zfs/arc.c +++ b/module/zfs/arc.c @@ -2132,8 +2132,10 @@ arc_buf_fill(arc_buf_t *buf, spa_t *spa, uint64_t dsobj, arc_fill_flags_t flags) if (HDR_PROTECTED(hdr)) { error = arc_fill_hdr_crypt(hdr, hash_lock, spa, dsobj, !!(flags & ARC_FILL_NOAUTH)); - if (error != 0) + if (error != 0) { + arc_hdr_set_flags(hdr, ARC_FLAG_IO_ERROR); return (error); + } } /* @@ -2234,6 +2236,7 @@ arc_buf_fill(arc_buf_t *buf, spa_t *spa, uint64_t dsobj, arc_fill_flags_t flags) "hdr %p, compress %d, psize %d, lsize %d", hdr, arc_hdr_get_compress(hdr), HDR_GET_PSIZE(hdr), HDR_GET_LSIZE(hdr)); + arc_hdr_set_flags(hdr, ARC_FLAG_IO_ERROR); return (SET_ERROR(EIO)); } } @@ -5815,7 +5818,9 @@ arc_read_done(zio_t *zio) acb->acb_compressed, acb->acb_noauth, B_TRUE, &acb->acb_buf); if (error != 0) { - arc_buf_destroy(acb->acb_buf, acb->acb_private); + (void) remove_reference(hdr, hash_lock, + acb->acb_private); + arc_buf_destroy_impl(acb->acb_buf); acb->acb_buf = NULL; } @@ -6058,7 +6063,9 @@ top: spa, NULL, zb, NULL, 0, 0); } if (rc != 0) { - arc_buf_destroy(buf, private); + (void) remove_reference(hdr, hash_lock, + private); + arc_buf_destroy_impl(buf); buf = NULL; } diff --git a/module/zfs/dmu_diff.c b/module/zfs/dmu_diff.c index 982b96132..76c32b126 100644 --- a/module/zfs/dmu_diff.c +++ b/module/zfs/dmu_diff.c @@ -131,11 +131,14 @@ diff_cb(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *abuf; arc_flags_t aflags = ARC_FLAG_WAIT; int blksz = BP_GET_LSIZE(bp); + int zio_flags = ZIO_FLAG_CANFAIL; int i; + if (BP_IS_PROTECTED(bp)) + zio_flags |= ZIO_FLAG_RAW; + if (arc_read(NULL, spa, bp, arc_getbuf_func, &abuf, - ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, - &aflags, zb) != 0) + ZIO_PRIORITY_ASYNC_READ, zio_flags, &aflags, zb) != 0) return (SET_ERROR(EIO)); blk = abuf->b_data; @@ -206,8 +209,17 @@ dmu_diff(const char *tosnap_name, const char *fromsnap_name, da.da_ddr.ddr_first = da.da_ddr.ddr_last = 0; da.da_err = 0; + /* + * Since zfs diff only looks at dnodes which are stored in plaintext + * (other than bonus buffers), we don't technically need to decrypt + * the dataset to perform this operation. However, the command line + * utility will still fail if the keys are not loaded because the + * dataset isn't mounted and because it will fail when it attempts to + * call the ZFS_IOC_OBJ_TO_STATS ioctl. + */ error = traverse_dataset(tosnap, fromtxg, - TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, diff_cb, &da); + TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA | TRAVERSE_NO_DECRYPT, + diff_cb, &da); if (error != 0) { da.da_err = error; diff --git a/tests/runfiles/linux.run b/tests/runfiles/linux.run index 6dc4df96c..62dfcf44e 100644 --- a/tests/runfiles/linux.run +++ b/tests/runfiles/linux.run @@ -150,7 +150,7 @@ tags = ['functional', 'cli_root', 'zfs_destroy'] [tests/functional/cli_root/zfs_diff] tests = ['zfs_diff_changes', 'zfs_diff_cliargs', 'zfs_diff_timestamp', - 'zfs_diff_types'] + 'zfs_diff_types', 'zfs_diff_encrypted'] tags = ['functional', 'cli_root', 'zfs_diff'] [tests/functional/cli_root/zfs_get] diff --git a/tests/zfs-tests/tests/functional/cli_root/zfs_diff/Makefile.am b/tests/zfs-tests/tests/functional/cli_root/zfs_diff/Makefile.am index afb45371a..db90e0585 100644 --- a/tests/zfs-tests/tests/functional/cli_root/zfs_diff/Makefile.am +++ b/tests/zfs-tests/tests/functional/cli_root/zfs_diff/Makefile.am @@ -7,6 +7,7 @@ dist_pkgdata_SCRIPTS = \ setup.ksh \ zfs_diff_changes.ksh \ zfs_diff_cliargs.ksh \ + zfs_diff_encrypted.ksh \ zfs_diff_timestamp.ksh \ zfs_diff_types.ksh diff --git a/tests/zfs-tests/tests/functional/cli_root/zfs_diff/zfs_diff_encrypted.ksh b/tests/zfs-tests/tests/functional/cli_root/zfs_diff/zfs_diff_encrypted.ksh new file mode 100755 index 000000000..471e9ca68 --- /dev/null +++ b/tests/zfs-tests/tests/functional/cli_root/zfs_diff/zfs_diff_encrypted.ksh @@ -0,0 +1,53 @@ +#!/bin/ksh -p +# +# This file and its contents are supplied under the terms of the +# Common Development and Distribution License ("CDDL"), version 1.0. +# You may only use this file in accordance with the terms of version +# 1.0 of the CDDL. +# +# A full copy of the text of the CDDL should have accompanied this +# source. A copy of the CDDL is also available via the Internet at +# http://www.illumos.org/license/CDDL. +# + +# +# Copyright 2018, Datto Inc. +# + +. $STF_SUITE/include/libtest.shlib + +# +# DESCRIPTION: +# 'zfs diff' should work with encrypted datasets +# +# STRATEGY: +# 1. Create an encrypted dataset +# 2. Create two snapshots of the dataset +# 3. Perform 'zfs diff -Ft' and verify no errors occur +# + +verify_runnable "both" + +function cleanup +{ + datasetexists $TESTPOOL/$TESTFS1 && \ + log_must zfs destroy -r $TESTPOOL/$TESTFS1 +} + +log_assert "'zfs diff' should work with encrypted datasets" +log_onexit cleanup + +# 1. Create an encrypted dataset +log_must eval "echo 'password' | zfs create -o encryption=on \ + -o keyformat=passphrase $TESTPOOL/$TESTFS1" +MNTPOINT="$(get_prop mountpoint $TESTPOOL/$TESTFS1)" + +# 2. Create two snapshots of the dataset +log_must zfs snapshot $TESTPOOL/$TESTFS1@snap1 +log_must touch "$MNTPOINT/file" +log_must zfs snapshot $TESTPOOL/$TESTFS1@snap2 + +# 3. Perform 'zfs diff' and verify no errors occur +log_must zfs diff -Ft $TESTPOOL/$TESTFS1@snap1 $TESTPOOL/$TESTFS1@snap2 + +log_pass "'zfs diff' works with encrypted datasets"