From: Darrick J. Wong <djwong@kernel.org>
Date: Wed, 12 Apr 2023 02:00:12 +0000 (-0700)
Subject: xfs: ensure that all metadata and data blocks are not cow staging extents
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=7ac14fa2bd22e99a06ae16382b394f697cfe2b8a;p=linux.git
xfs: ensure that all metadata and data blocks are not cow staging extents
Make sure that all filesystem metadata blocks and file data blocks are
not also marked as CoW staging extents. The extra checking added here
was inspired by an actual VM host filesystem corruption incident due to
bugs in the CoW handling of 4.x kernels.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
---
diff --git a/fs/xfs/scrub/agheader.c b/fs/xfs/scrub/agheader.c
index 87cb13a6e84a0..1a84153afa917 100644
--- a/fs/xfs/scrub/agheader.c
+++ b/fs/xfs/scrub/agheader.c
@@ -53,6 +53,7 @@ xchk_superblock_xref(
xchk_xref_is_not_inode_chunk(sc, agbno, 1);
xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
xchk_xref_is_not_shared(sc, agbno, 1);
+ xchk_xref_is_not_cow_staging(sc, agbno, 1);
/* scrub teardown will take care of sc->sa for us */
}
@@ -517,6 +518,7 @@ xchk_agf_xref(
xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
xchk_agf_xref_btreeblks(sc);
xchk_xref_is_not_shared(sc, agbno, 1);
+ xchk_xref_is_not_cow_staging(sc, agbno, 1);
xchk_agf_xref_refcblks(sc);
/* scrub teardown will take care of sc->sa for us */
@@ -644,6 +646,7 @@ xchk_agfl_block_xref(
xchk_xref_is_not_inode_chunk(sc, agbno, 1);
xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_AG);
xchk_xref_is_not_shared(sc, agbno, 1);
+ xchk_xref_is_not_cow_staging(sc, agbno, 1);
}
/* Scrub an AGFL block. */
@@ -700,6 +703,7 @@ xchk_agfl_xref(
xchk_xref_is_not_inode_chunk(sc, agbno, 1);
xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
xchk_xref_is_not_shared(sc, agbno, 1);
+ xchk_xref_is_not_cow_staging(sc, agbno, 1);
/*
* Scrub teardown will take care of sc->sa for us. Leave sc->sa
@@ -855,6 +859,7 @@ xchk_agi_xref(
xchk_agi_xref_icounts(sc);
xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_FS);
xchk_xref_is_not_shared(sc, agbno, 1);
+ xchk_xref_is_not_cow_staging(sc, agbno, 1);
xchk_agi_xref_fiblocks(sc);
/* scrub teardown will take care of sc->sa for us */
diff --git a/fs/xfs/scrub/alloc.c b/fs/xfs/scrub/alloc.c
index 5920fe051543e..12dd55ac2a4f1 100644
--- a/fs/xfs/scrub/alloc.c
+++ b/fs/xfs/scrub/alloc.c
@@ -90,6 +90,7 @@ xchk_allocbt_xref(
xchk_xref_is_not_inode_chunk(sc, agbno, len);
xchk_xref_has_no_owner(sc, agbno, len);
xchk_xref_is_not_shared(sc, agbno, len);
+ xchk_xref_is_not_cow_staging(sc, agbno, len);
}
/* Scrub a bnobt/cntbt record. */
diff --git a/fs/xfs/scrub/bmap.c b/fs/xfs/scrub/bmap.c
index 6188eba672e54..be2c4da2808ba 100644
--- a/fs/xfs/scrub/bmap.c
+++ b/fs/xfs/scrub/bmap.c
@@ -328,12 +328,17 @@ xchk_bmap_iextent_xref(
xchk_bmap_xref_rmap(info, irec, agbno);
switch (info->whichfork) {
case XFS_DATA_FORK:
- if (xfs_is_reflink_inode(info->sc->ip))
- break;
- fallthrough;
+ if (!xfs_is_reflink_inode(info->sc->ip))
+ xchk_xref_is_not_shared(info->sc, agbno,
+ irec->br_blockcount);
+ xchk_xref_is_not_cow_staging(info->sc, agbno,
+ irec->br_blockcount);
+ break;
case XFS_ATTR_FORK:
xchk_xref_is_not_shared(info->sc, agbno,
irec->br_blockcount);
+ xchk_xref_is_not_cow_staging(info->sc, agbno,
+ irec->br_blockcount);
break;
case XFS_COW_FORK:
xchk_xref_is_cow_staging(info->sc, agbno,
diff --git a/fs/xfs/scrub/ialloc.c b/fs/xfs/scrub/ialloc.c
index ca5a7e0f5451c..6d08613db32f0 100644
--- a/fs/xfs/scrub/ialloc.c
+++ b/fs/xfs/scrub/ialloc.c
@@ -115,7 +115,7 @@ xchk_iallocbt_chunk(
xchk_btree_set_corrupt(bs->sc, bs->cur, 0);
xchk_iallocbt_chunk_xref(bs->sc, irec, agino, bno, len);
-
+ xchk_xref_is_not_cow_staging(bs->sc, bno, len);
return true;
}
diff --git a/fs/xfs/scrub/inode.c b/fs/xfs/scrub/inode.c
index bbf9432c02c2c..50ebd72f6d959 100644
--- a/fs/xfs/scrub/inode.c
+++ b/fs/xfs/scrub/inode.c
@@ -558,6 +558,7 @@ xchk_inode_xref(
xchk_inode_xref_finobt(sc, ino);
xchk_xref_is_owned_by(sc, agbno, 1, &XFS_RMAP_OINFO_INODES);
xchk_xref_is_not_shared(sc, agbno, 1);
+ xchk_xref_is_not_cow_staging(sc, agbno, 1);
xchk_inode_xref_bmap(sc, dip);
out_free:
diff --git a/fs/xfs/scrub/refcount.c b/fs/xfs/scrub/refcount.c
index 771a591a4aeba..db9e46a4f8d43 100644
--- a/fs/xfs/scrub/refcount.c
+++ b/fs/xfs/scrub/refcount.c
@@ -555,3 +555,24 @@ xchk_xref_is_not_shared(
if (outcome != XBTREE_RECPACKING_EMPTY)
xchk_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
}
+
+/* xref check that the extent is not being used for CoW staging. */
+void
+xchk_xref_is_not_cow_staging(
+ struct xfs_scrub *sc,
+ xfs_agblock_t agbno,
+ xfs_extlen_t len)
+{
+ enum xbtree_recpacking outcome;
+ int error;
+
+ if (!sc->sa.refc_cur || xchk_skip_xref(sc->sm))
+ return;
+
+ error = xfs_refcount_has_records(sc->sa.refc_cur, XFS_REFC_DOMAIN_COW,
+ agbno, len, &outcome);
+ if (!xchk_should_check_xref(sc, &error, &sc->sa.refc_cur))
+ return;
+ if (outcome != XBTREE_RECPACKING_EMPTY)
+ xchk_btree_xref_set_corrupt(sc, sc->sa.refc_cur, 0);
+}
diff --git a/fs/xfs/scrub/scrub.h b/fs/xfs/scrub/scrub.h
index d85c3b883b4ce..b6f452eb9645e 100644
--- a/fs/xfs/scrub/scrub.h
+++ b/fs/xfs/scrub/scrub.h
@@ -172,6 +172,8 @@ void xchk_xref_is_cow_staging(struct xfs_scrub *sc, xfs_agblock_t bno,
xfs_extlen_t len);
void xchk_xref_is_not_shared(struct xfs_scrub *sc, xfs_agblock_t bno,
xfs_extlen_t len);
+void xchk_xref_is_not_cow_staging(struct xfs_scrub *sc, xfs_agblock_t bno,
+ xfs_extlen_t len);
#ifdef CONFIG_XFS_RT
void xchk_xref_is_used_rt_space(struct xfs_scrub *sc, xfs_rtblock_t rtbno,
xfs_extlen_t len);