[PATCH 00/10] xfs: strengthen log intent validation

[PATCH 00/10] xfs: strengthen log intent validation

[Darrick J. Wong]

Hi all,

This patchset hoists the code that checks log intent record validation
into separate functions, and reworks them to use the standard field
validation predicates instead of open-coding them.  This strengthens log
recovery against (some) fuzzed log items.

If you're going to start using this mess, you probably ought to just
pull from my git trees, which are linked below.

This is an extraordinary way to destroy everything.  Enjoy!
Comments and questions are, as always, welcome.

--D

kernel git tree:
https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=fix-recovered-log-intent-validation-5.11
---
 fs/xfs/xfs_bmap_item.c     |   75 ++++++++++++++++++++++++++++----------------
 fs/xfs/xfs_extfree_item.c  |   31 ++++++++++++------
 fs/xfs/xfs_log_recover.c   |    5 ++-
 fs/xfs/xfs_refcount_item.c |   61 ++++++++++++++++++++++--------------
 fs/xfs/xfs_rmap_item.c     |   75 ++++++++++++++++++++++++++++----------------
 fs/xfs/xfs_trace.h         |   19 +++++++++++
 6 files changed, 178 insertions(+), 88 deletions(-)

[PATCH 01/10] xfs: hoist recovered bmap intent checks out of xfs_bui_item_recover

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

When we recover a bmap intent from the log, we need to validate its
contents before we try to replay them.  Hoist the checking code into a
separate function in preparation to refactor this code to use validation
helpers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_bmap_item.c |   71 ++++++++++++++++++++++++++++++------------------
 1 file changed, 44 insertions(+), 27 deletions(-)


diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c
index 9e16a4d0f97c..c90d018fbc2e 100644
--- a/fs/xfs/xfs_bmap_item.c
+++ b/fs/xfs/xfs_bmap_item.c
@@ -417,6 +417,49 @@ const struct xfs_defer_op_type xfs_bmap_update_defer_type = {
 	.cancel_item	= xfs_bmap_update_cancel_item,
 };
 
+/* Is this recovered BUI ok? */
+static inline bool
+xfs_bui_validate(
+	struct xfs_mount		*mp,
+	struct xfs_bui_log_item		*buip)
+{
+	struct xfs_map_extent		*bmap;
+	xfs_fsblock_t			startblock_fsb;
+	xfs_fsblock_t			inode_fsb;
+
+	/* Only one mapping operation per BUI... */
+	if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
+		return false;
+
+	bmap = &buip->bui_format.bui_extents[0];
+	startblock_fsb = XFS_BB_TO_FSB(mp,
+			XFS_FSB_TO_DADDR(mp, bmap->me_startblock));
+	inode_fsb = XFS_BB_TO_FSB(mp, XFS_FSB_TO_DADDR(mp,
+			XFS_INO_TO_FSB(mp, bmap->me_owner)));
+
+	if (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS)
+		return false;
+
+	switch (bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK) {
+	case XFS_BMAP_MAP:
+	case XFS_BMAP_UNMAP:
+		break;
+	default:
+		return false;
+	}
+
+	if (startblock_fsb == 0 ||
+	    bmap->me_len == 0 ||
+	    inode_fsb == 0 ||
+	    startblock_fsb >= mp->m_sb.sb_dblocks ||
+	    bmap->me_len >= mp->m_sb.sb_agblocks ||
+	    inode_fsb >= mp->m_sb.sb_dblocks ||
+	    (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS))
+		return false;
+
+	return true;
+}
+
 /*
  * Process a bmap update intent item that was recovered from the log.
  * We need to update some inode's bmbt.
@@ -433,47 +476,21 @@ xfs_bui_item_recover(
 	struct xfs_mount		*mp = lip->li_mountp;
 	struct xfs_map_extent		*bmap;
 	struct xfs_bud_log_item		*budp;
-	xfs_fsblock_t			startblock_fsb;
-	xfs_fsblock_t			inode_fsb;
 	xfs_filblks_t			count;
 	xfs_exntst_t			state;
 	unsigned int			bui_type;
 	int				whichfork;
 	int				error = 0;
 
-	/* Only one mapping operation per BUI... */
-	if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
+	if (!xfs_bui_validate(mp, buip))
 		return -EFSCORRUPTED;
 
-	/*
-	 * First check the validity of the extent described by the
-	 * BUI.  If anything is bad, then toss the BUI.
-	 */
 	bmap = &buip->bui_format.bui_extents[0];
-	startblock_fsb = XFS_BB_TO_FSB(mp,
-			   XFS_FSB_TO_DADDR(mp, bmap->me_startblock));
-	inode_fsb = XFS_BB_TO_FSB(mp, XFS_FSB_TO_DADDR(mp,
-			XFS_INO_TO_FSB(mp, bmap->me_owner)));
 	state = (bmap->me_flags & XFS_BMAP_EXTENT_UNWRITTEN) ?
 			XFS_EXT_UNWRITTEN : XFS_EXT_NORM;
 	whichfork = (bmap->me_flags & XFS_BMAP_EXTENT_ATTR_FORK) ?
 			XFS_ATTR_FORK : XFS_DATA_FORK;
 	bui_type = bmap->me_flags & XFS_BMAP_EXTENT_TYPE_MASK;
-	switch (bui_type) {
-	case XFS_BMAP_MAP:
-	case XFS_BMAP_UNMAP:
-		break;
-	default:
-		return -EFSCORRUPTED;
-	}
-	if (startblock_fsb == 0 ||
-	    bmap->me_len == 0 ||
-	    inode_fsb == 0 ||
-	    startblock_fsb >= mp->m_sb.sb_dblocks ||
-	    bmap->me_len >= mp->m_sb.sb_agblocks ||
-	    inode_fsb >= mp->m_sb.sb_dblocks ||
-	    (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS))
-		return -EFSCORRUPTED;
 
 	/* Grab the inode. */
 	error = xfs_iget(mp, NULL, bmap->me_owner, 0, 0, &ip);

Re: [PATCH 01/10] xfs: hoist recovered bmap intent checks out of xfs_bui_item_recover

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:37:46PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> When we recover a bmap intent from the log, we need to validate its
> contents before we try to replay them.  Hoist the checking code into a
> separate function in preparation to refactor this code to use validation
> helpers.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 02/10] xfs: improve the code that checks recovered bmap intent items

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

The code that validates recovered bmap intent items is kind of a mess --
it doesn't use the standard xfs type validators, and it doesn't check
for things that it should.  Fix the validator function to use the
standard validation helpers and look for more types of obvious errors.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_bmap_item.c |   26 +++++++++++++-------------
 1 file changed, 13 insertions(+), 13 deletions(-)


diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c
index c90d018fbc2e..19f89a6b65a1 100644
--- a/fs/xfs/xfs_bmap_item.c
+++ b/fs/xfs/xfs_bmap_item.c
@@ -424,18 +424,13 @@ xfs_bui_validate(
 	struct xfs_bui_log_item		*buip)
 {
 	struct xfs_map_extent		*bmap;
-	xfs_fsblock_t			startblock_fsb;
-	xfs_fsblock_t			inode_fsb;
+	xfs_fsblock_t			end;
 
 	/* Only one mapping operation per BUI... */
 	if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
 		return false;
 
 	bmap = &buip->bui_format.bui_extents[0];
-	startblock_fsb = XFS_BB_TO_FSB(mp,
-			XFS_FSB_TO_DADDR(mp, bmap->me_startblock));
-	inode_fsb = XFS_BB_TO_FSB(mp, XFS_FSB_TO_DADDR(mp,
-			XFS_INO_TO_FSB(mp, bmap->me_owner)));
 
 	if (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS)
 		return false;
@@ -448,13 +443,18 @@ xfs_bui_validate(
 		return false;
 	}
 
-	if (startblock_fsb == 0 ||
-	    bmap->me_len == 0 ||
-	    inode_fsb == 0 ||
-	    startblock_fsb >= mp->m_sb.sb_dblocks ||
-	    bmap->me_len >= mp->m_sb.sb_agblocks ||
-	    inode_fsb >= mp->m_sb.sb_dblocks ||
-	    (bmap->me_flags & ~XFS_BMAP_EXTENT_FLAGS))
+	if (!xfs_verify_ino(mp, bmap->me_owner))
+		return false;
+
+	if (bmap->me_startoff + bmap->me_len <= bmap->me_startoff)
+		return false;
+
+	if (bmap->me_startblock + bmap->me_len <= bmap->me_startblock)
+		return false;
+
+	end = bmap->me_startblock + bmap->me_len - 1;
+	if (!xfs_verify_fsbno(mp, bmap->me_startblock) ||
+	    !xfs_verify_fsbno(mp, end))
 		return false;
 
 	return true;

Re: [PATCH 02/10] xfs: improve the code that checks recovered bmap intent items

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:37:52PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> The code that validates recovered bmap intent items is kind of a mess --
> it doesn't use the standard xfs type validators, and it doesn't check
> for things that it should.  Fix the validator function to use the
> standard validation helpers and look for more types of obvious errors.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
> ---

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 03/10] xfs: hoist recovered rmap intent checks out of xfs_rui_item_recover

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

When we recover a rmap intent from the log, we need to validate its
contents before we try to replay them.  Hoist the checking code into a
separate function in preparation to refactor this code to use validation
helpers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_rmap_item.c |   65 ++++++++++++++++++++++++++++--------------------
 1 file changed, 38 insertions(+), 27 deletions(-)


diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c
index 7adc996ca6e3..871ed7fc43ee 100644
--- a/fs/xfs/xfs_rmap_item.c
+++ b/fs/xfs/xfs_rmap_item.c
@@ -460,6 +460,42 @@ const struct xfs_defer_op_type xfs_rmap_update_defer_type = {
 	.cancel_item	= xfs_rmap_update_cancel_item,
 };
 
+/* Is this recovered RUI ok? */
+static inline bool
+xfs_rui_validate_map(
+	struct xfs_mount		*mp,
+	struct xfs_map_extent		*rmap)
+{
+	xfs_fsblock_t			startblock_fsb;
+	bool				op_ok;
+
+	startblock_fsb = XFS_BB_TO_FSB(mp,
+			   XFS_FSB_TO_DADDR(mp, rmap->me_startblock));
+	switch (rmap->me_flags & XFS_RMAP_EXTENT_TYPE_MASK) {
+	case XFS_RMAP_EXTENT_MAP:
+	case XFS_RMAP_EXTENT_MAP_SHARED:
+	case XFS_RMAP_EXTENT_UNMAP:
+	case XFS_RMAP_EXTENT_UNMAP_SHARED:
+	case XFS_RMAP_EXTENT_CONVERT:
+	case XFS_RMAP_EXTENT_CONVERT_SHARED:
+	case XFS_RMAP_EXTENT_ALLOC:
+	case XFS_RMAP_EXTENT_FREE:
+		op_ok = true;
+		break;
+	default:
+		op_ok = false;
+		break;
+	}
+	if (!op_ok || startblock_fsb == 0 ||
+	    rmap->me_len == 0 ||
+	    startblock_fsb >= mp->m_sb.sb_dblocks ||
+	    rmap->me_len >= mp->m_sb.sb_agblocks ||
+	    (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS))
+		return false;
+
+	return true;
+}
+
 /*
  * Process an rmap update intent item that was recovered from the log.
  * We need to update the rmapbt.
@@ -475,10 +511,8 @@ xfs_rui_item_recover(
 	struct xfs_trans		*tp;
 	struct xfs_btree_cur		*rcur = NULL;
 	struct xfs_mount		*mp = lip->li_mountp;
-	xfs_fsblock_t			startblock_fsb;
 	enum xfs_rmap_intent_type	type;
 	xfs_exntst_t			state;
-	bool				op_ok;
 	int				i;
 	int				whichfork;
 	int				error = 0;
@@ -488,32 +522,9 @@ xfs_rui_item_recover(
 	 * RUI.  If any are bad, then assume that all are bad and
 	 * just toss the RUI.
 	 */
-	for (i = 0; i < ruip->rui_format.rui_nextents; i++) {
-		rmap = &ruip->rui_format.rui_extents[i];
-		startblock_fsb = XFS_BB_TO_FSB(mp,
-				   XFS_FSB_TO_DADDR(mp, rmap->me_startblock));
-		switch (rmap->me_flags & XFS_RMAP_EXTENT_TYPE_MASK) {
-		case XFS_RMAP_EXTENT_MAP:
-		case XFS_RMAP_EXTENT_MAP_SHARED:
-		case XFS_RMAP_EXTENT_UNMAP:
-		case XFS_RMAP_EXTENT_UNMAP_SHARED:
-		case XFS_RMAP_EXTENT_CONVERT:
-		case XFS_RMAP_EXTENT_CONVERT_SHARED:
-		case XFS_RMAP_EXTENT_ALLOC:
-		case XFS_RMAP_EXTENT_FREE:
-			op_ok = true;
-			break;
-		default:
-			op_ok = false;
-			break;
-		}
-		if (!op_ok || startblock_fsb == 0 ||
-		    rmap->me_len == 0 ||
-		    startblock_fsb >= mp->m_sb.sb_dblocks ||
-		    rmap->me_len >= mp->m_sb.sb_agblocks ||
-		    (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS))
+	for (i = 0; i < ruip->rui_format.rui_nextents; i++)
+		if (!xfs_rui_validate_map(mp, &ruip->rui_format.rui_extents[i]))
 			return -EFSCORRUPTED;
-	}
 
 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate,
 			mp->m_rmap_maxlevels, 0, XFS_TRANS_RESERVE, &tp);

Re: [PATCH 03/10] xfs: hoist recovered rmap intent checks out of xfs_rui_item_recover

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:37:58PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> When we recover a rmap intent from the log, we need to validate its
> contents before we try to replay them.  Hoist the checking code into a
> separate function in preparation to refactor this code to use validation
> helpers.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 04/10] xfs: improve the code that checks recovered rmap intent items

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

The code that validates recovered rmap intent items is kind of a mess --
it doesn't use the standard xfs type validators, and it doesn't check
for things that it should.  Fix the validator function to use the
standard validation helpers and look for more types of obvious errors.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_rmap_item.c |   31 +++++++++++++++++++------------
 1 file changed, 19 insertions(+), 12 deletions(-)


diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c
index 871ed7fc43ee..2779cbee8fa8 100644
--- a/fs/xfs/xfs_rmap_item.c
+++ b/fs/xfs/xfs_rmap_item.c
@@ -466,11 +466,11 @@ xfs_rui_validate_map(
 	struct xfs_mount		*mp,
 	struct xfs_map_extent		*rmap)
 {
-	xfs_fsblock_t			startblock_fsb;
-	bool				op_ok;
+	xfs_fsblock_t			end;
+
+	if (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS)
+		return false;
 
-	startblock_fsb = XFS_BB_TO_FSB(mp,
-			   XFS_FSB_TO_DADDR(mp, rmap->me_startblock));
 	switch (rmap->me_flags & XFS_RMAP_EXTENT_TYPE_MASK) {
 	case XFS_RMAP_EXTENT_MAP:
 	case XFS_RMAP_EXTENT_MAP_SHARED:
@@ -480,17 +480,24 @@ xfs_rui_validate_map(
 	case XFS_RMAP_EXTENT_CONVERT_SHARED:
 	case XFS_RMAP_EXTENT_ALLOC:
 	case XFS_RMAP_EXTENT_FREE:
-		op_ok = true;
 		break;
 	default:
-		op_ok = false;
-		break;
+		return false;
 	}
-	if (!op_ok || startblock_fsb == 0 ||
-	    rmap->me_len == 0 ||
-	    startblock_fsb >= mp->m_sb.sb_dblocks ||
-	    rmap->me_len >= mp->m_sb.sb_agblocks ||
-	    (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS))
+
+	if (!xfs_verify_ino(mp, rmap->me_owner) &&
+	    !XFS_RMAP_NON_INODE_OWNER(rmap->me_owner))
+		return false;
+
+	if (rmap->me_startoff + rmap->me_len <= rmap->me_startoff)
+		return false;
+
+	if (rmap->me_startblock + rmap->me_len <= rmap->me_startblock)
+		return false;
+
+	end = rmap->me_startblock + rmap->me_len - 1;
+	if (!xfs_verify_fsbno(mp, rmap->me_startblock) ||
+	    !xfs_verify_fsbno(mp, end))
 		return false;
 
 	return true;

Re: [PATCH 04/10] xfs: improve the code that checks recovered rmap intent items

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:38:04PM -0800, Darrick J. Wong wrote:
> +	if (!xfs_verify_ino(mp, rmap->me_owner) &&
> +	    !XFS_RMAP_NON_INODE_OWNER(rmap->me_owner))
> +		return false;

Wouldn't it make sense to reverse the order of the checks here?

> +	end = rmap->me_startblock + rmap->me_len - 1;
> +	if (!xfs_verify_fsbno(mp, rmap->me_startblock) ||
> +	    !xfs_verify_fsbno(mp, end))
>  		return false;

Nit: why not simply:

	if (!xfs_verify_fsbno(mp, rmap->me_startblock))
		return false;
	if (!xfs_verify_fsbno(mp, rmap->me_startblock + rmap->me_len - 1))
		return false;

?

Re: [PATCH 04/10] xfs: improve the code that checks recovered rmap intent items

[Darrick J. Wong]

On Tue, Dec 01, 2020 at 10:05:35AM +0000, Christoph Hellwig wrote:
> On Mon, Nov 30, 2020 at 07:38:04PM -0800, Darrick J. Wong wrote:
> > +	if (!xfs_verify_ino(mp, rmap->me_owner) &&
> > +	    !XFS_RMAP_NON_INODE_OWNER(rmap->me_owner))
> > +		return false;
> 
> Wouldn't it make sense to reverse the order of the checks here?

Yep.  Fixed.

> > +	end = rmap->me_startblock + rmap->me_len - 1;
> > +	if (!xfs_verify_fsbno(mp, rmap->me_startblock) ||
> > +	    !xfs_verify_fsbno(mp, end))
> >  		return false;
> 
> Nit: why not simply:
> 
> 	if (!xfs_verify_fsbno(mp, rmap->me_startblock))
> 		return false;
> 	if (!xfs_verify_fsbno(mp, rmap->me_startblock + rmap->me_len - 1))
> 		return false;
> 
> ?

Yeah.

--D

[PATCH v2 04/10] xfs: improve the code that checks recovered rmap intent items

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

The code that validates recovered rmap intent items is kind of a mess --
it doesn't use the standard xfs type validators, and it doesn't check
for things that it should.  Fix the validator function to use the
standard validation helpers and look for more types of obvious errors.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
v2: reverse the owner tests, simplify the startblock checks
---
 fs/xfs/xfs_rmap_item.c |   30 ++++++++++++++++++------------
 1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c
index 871ed7fc43ee..36fe368531d2 100644
--- a/fs/xfs/xfs_rmap_item.c
+++ b/fs/xfs/xfs_rmap_item.c
@@ -466,11 +466,9 @@ xfs_rui_validate_map(
 	struct xfs_mount		*mp,
 	struct xfs_map_extent		*rmap)
 {
-	xfs_fsblock_t			startblock_fsb;
-	bool				op_ok;
+	if (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS)
+		return false;
 
-	startblock_fsb = XFS_BB_TO_FSB(mp,
-			   XFS_FSB_TO_DADDR(mp, rmap->me_startblock));
 	switch (rmap->me_flags & XFS_RMAP_EXTENT_TYPE_MASK) {
 	case XFS_RMAP_EXTENT_MAP:
 	case XFS_RMAP_EXTENT_MAP_SHARED:
@@ -480,17 +478,25 @@ xfs_rui_validate_map(
 	case XFS_RMAP_EXTENT_CONVERT_SHARED:
 	case XFS_RMAP_EXTENT_ALLOC:
 	case XFS_RMAP_EXTENT_FREE:
-		op_ok = true;
 		break;
 	default:
-		op_ok = false;
-		break;
+		return false;
 	}
-	if (!op_ok || startblock_fsb == 0 ||
-	    rmap->me_len == 0 ||
-	    startblock_fsb >= mp->m_sb.sb_dblocks ||
-	    rmap->me_len >= mp->m_sb.sb_agblocks ||
-	    (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS))
+
+	if (!XFS_RMAP_NON_INODE_OWNER(rmap->me_owner) &&
+	    !xfs_verify_ino(mp, rmap->me_owner))
+		return false;
+
+	if (rmap->me_startoff + rmap->me_len <= rmap->me_startoff)
+		return false;
+
+	if (rmap->me_startblock + rmap->me_len <= rmap->me_startblock)
+		return false;
+
+	if (!xfs_verify_fsbno(mp, rmap->me_startblock))
+		return false;
+
+	if (!xfs_verify_fsbno(mp, rmap->me_startblock + rmap->me_len - 1))
 		return false;
 
 	return true;

[PATCH 05/10] xfs: hoist recovered refcount intent checks out of xfs_cui_item_recover

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

When we recover a refcount intent from the log, we need to validate its
contents before we try to replay them.  Hoist the checking code into a
separate function in preparation to refactor this code to use validation
helpers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_refcount_item.c |   58 +++++++++++++++++++++++++++-----------------
 1 file changed, 35 insertions(+), 23 deletions(-)


diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c
index 7529eb63ce94..de344bd7e73c 100644
--- a/fs/xfs/xfs_refcount_item.c
+++ b/fs/xfs/xfs_refcount_item.c
@@ -417,6 +417,38 @@ const struct xfs_defer_op_type xfs_refcount_update_defer_type = {
 	.cancel_item	= xfs_refcount_update_cancel_item,
 };
 
+/* Is this recovered CUI ok? */
+static inline bool
+xfs_cui_validate_phys(
+	struct xfs_mount		*mp,
+	struct xfs_phys_extent		*refc)
+{
+	xfs_fsblock_t			startblock_fsb;
+	bool				op_ok;
+
+	startblock_fsb = XFS_BB_TO_FSB(mp,
+			   XFS_FSB_TO_DADDR(mp, refc->pe_startblock));
+	switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
+	case XFS_REFCOUNT_INCREASE:
+	case XFS_REFCOUNT_DECREASE:
+	case XFS_REFCOUNT_ALLOC_COW:
+	case XFS_REFCOUNT_FREE_COW:
+		op_ok = true;
+		break;
+	default:
+		op_ok = false;
+		break;
+	}
+	if (!op_ok || startblock_fsb == 0 ||
+	    refc->pe_len == 0 ||
+	    startblock_fsb >= mp->m_sb.sb_dblocks ||
+	    refc->pe_len >= mp->m_sb.sb_agblocks ||
+	    (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS))
+		return false;
+
+	return true;
+}
+
 /*
  * Process a refcount update intent item that was recovered from the log.
  * We need to update the refcountbt.
@@ -433,11 +465,9 @@ xfs_cui_item_recover(
 	struct xfs_trans		*tp;
 	struct xfs_btree_cur		*rcur = NULL;
 	struct xfs_mount		*mp = lip->li_mountp;
-	xfs_fsblock_t			startblock_fsb;
 	xfs_fsblock_t			new_fsb;
 	xfs_extlen_t			new_len;
 	unsigned int			refc_type;
-	bool				op_ok;
 	bool				requeue_only = false;
 	enum xfs_refcount_intent_type	type;
 	int				i;
@@ -448,28 +478,10 @@ xfs_cui_item_recover(
 	 * CUI.  If any are bad, then assume that all are bad and
 	 * just toss the CUI.
 	 */
-	for (i = 0; i < cuip->cui_format.cui_nextents; i++) {
-		refc = &cuip->cui_format.cui_extents[i];
-		startblock_fsb = XFS_BB_TO_FSB(mp,
-				   XFS_FSB_TO_DADDR(mp, refc->pe_startblock));
-		switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
-		case XFS_REFCOUNT_INCREASE:
-		case XFS_REFCOUNT_DECREASE:
-		case XFS_REFCOUNT_ALLOC_COW:
-		case XFS_REFCOUNT_FREE_COW:
-			op_ok = true;
-			break;
-		default:
-			op_ok = false;
-			break;
-		}
-		if (!op_ok || startblock_fsb == 0 ||
-		    refc->pe_len == 0 ||
-		    startblock_fsb >= mp->m_sb.sb_dblocks ||
-		    refc->pe_len >= mp->m_sb.sb_agblocks ||
-		    (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS))
+	for (i = 0; i < cuip->cui_format.cui_nextents; i++)
+		if (!xfs_cui_validate_phys(mp,
+					   &cuip->cui_format.cui_extents[i]))
 			return -EFSCORRUPTED;
-	}
 
 	/*
 	 * Under normal operation, refcount updates are deferred, so we

Re: [PATCH 05/10] xfs: hoist recovered refcount intent checks out of xfs_cui_item_recover

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:38:10PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> When we recover a refcount intent from the log, we need to validate its
> contents before we try to replay them.  Hoist the checking code into a
> separate function in preparation to refactor this code to use validation
> helpers.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 06/10] xfs: improve the code that checks recovered refcount intent items

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

The code that validates recovered refcount intent items is kind of a
mess -- it doesn't use the standard xfs type validators, and it doesn't
check for things that it should.  Fix the validator function to use the
standard validation helpers and look for more types of obvious errors.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_refcount_item.c |   24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)


diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c
index de344bd7e73c..20e5c22bb754 100644
--- a/fs/xfs/xfs_refcount_item.c
+++ b/fs/xfs/xfs_refcount_item.c
@@ -423,27 +423,27 @@ xfs_cui_validate_phys(
 	struct xfs_mount		*mp,
 	struct xfs_phys_extent		*refc)
 {
-	xfs_fsblock_t			startblock_fsb;
-	bool				op_ok;
+	xfs_fsblock_t			end;
+
+	if (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS)
+		return false;
 
-	startblock_fsb = XFS_BB_TO_FSB(mp,
-			   XFS_FSB_TO_DADDR(mp, refc->pe_startblock));
 	switch (refc->pe_flags & XFS_REFCOUNT_EXTENT_TYPE_MASK) {
 	case XFS_REFCOUNT_INCREASE:
 	case XFS_REFCOUNT_DECREASE:
 	case XFS_REFCOUNT_ALLOC_COW:
 	case XFS_REFCOUNT_FREE_COW:
-		op_ok = true;
 		break;
 	default:
-		op_ok = false;
-		break;
+		return false;
 	}
-	if (!op_ok || startblock_fsb == 0 ||
-	    refc->pe_len == 0 ||
-	    startblock_fsb >= mp->m_sb.sb_dblocks ||
-	    refc->pe_len >= mp->m_sb.sb_agblocks ||
-	    (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS))
+
+	if (refc->pe_startblock + refc->pe_len <= refc->pe_startblock)
+		return false;
+
+	end = refc->pe_startblock + refc->pe_len - 1;
+	if (!xfs_verify_fsbno(mp, refc->pe_startblock) ||
+	    !xfs_verify_fsbno(mp, end))
 		return false;
 
 	return true;

Re: [PATCH 06/10] xfs: improve the code that checks recovered refcount intent items

[Christoph Hellwig]

Looks good (minus the same nitpick as for the other one):

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 07/10] xfs: hoist recovered extent-free intent checks out of xfs_efi_item_recover

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

When we recover a extent-free intent from the log, we need to validate
its contents before we try to replay them.  Hoist the checking code into
a separate function in preparation to refactor this code to use
validation helpers.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_extfree_item.c |   31 +++++++++++++++++++++----------
 1 file changed, 21 insertions(+), 10 deletions(-)


diff --git a/fs/xfs/xfs_extfree_item.c b/fs/xfs/xfs_extfree_item.c
index 6c11bfc3d452..b5710b7fc263 100644
--- a/fs/xfs/xfs_extfree_item.c
+++ b/fs/xfs/xfs_extfree_item.c
@@ -578,6 +578,25 @@ const struct xfs_defer_op_type xfs_agfl_free_defer_type = {
 	.cancel_item	= xfs_extent_free_cancel_item,
 };
 
+/* Is this recovered EFI ok? */
+static inline bool
+xfs_efi_validate_ext(
+	struct xfs_mount		*mp,
+	struct xfs_extent		*extp)
+{
+	xfs_fsblock_t			startblock_fsb;
+
+	startblock_fsb = XFS_BB_TO_FSB(mp,
+			   XFS_FSB_TO_DADDR(mp, extp->ext_start));
+	if (startblock_fsb == 0 ||
+	    extp->ext_len == 0 ||
+	    startblock_fsb >= mp->m_sb.sb_dblocks ||
+	    extp->ext_len >= mp->m_sb.sb_agblocks)
+		return false;
+
+	return true;
+}
+
 /*
  * Process an extent free intent item that was recovered from
  * the log.  We need to free the extents that it describes.
@@ -592,7 +611,6 @@ xfs_efi_item_recover(
 	struct xfs_efd_log_item		*efdp;
 	struct xfs_trans		*tp;
 	struct xfs_extent		*extp;
-	xfs_fsblock_t			startblock_fsb;
 	int				i;
 	int				error = 0;
 
@@ -601,16 +619,9 @@ xfs_efi_item_recover(
 	 * EFI.  If any are bad, then assume that all are bad and
 	 * just toss the EFI.
 	 */
-	for (i = 0; i < efip->efi_format.efi_nextents; i++) {
-		extp = &efip->efi_format.efi_extents[i];
-		startblock_fsb = XFS_BB_TO_FSB(mp,
-				   XFS_FSB_TO_DADDR(mp, extp->ext_start));
-		if (startblock_fsb == 0 ||
-		    extp->ext_len == 0 ||
-		    startblock_fsb >= mp->m_sb.sb_dblocks ||
-		    extp->ext_len >= mp->m_sb.sb_agblocks)
+	for (i = 0; i < efip->efi_format.efi_nextents; i++)
+		if (!xfs_efi_validate_ext(mp, &efip->efi_format.efi_extents[i]))
 			return -EFSCORRUPTED;
-	}
 
 	error = xfs_trans_alloc(mp, &M_RES(mp)->tr_itruncate, 0, 0, 0, &tp);
 	if (error)

Re: [PATCH 07/10] xfs: hoist recovered extent-free intent checks out of xfs_efi_item_recover

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:38:22PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> When we recover a extent-free intent from the log, we need to validate
> its contents before we try to replay them.  Hoist the checking code into
> a separate function in preparation to refactor this code to use
> validation helpers.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 08/10] xfs: improve the code that checks recovered extent-free intent items

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

The code that validates recovered extent-free intent items is kind of a
mess -- it doesn't use the standard xfs type validators, and it doesn't
check for things that it should.  Fix the validator function to use the
standard validation helpers and look for more types of obvious errors.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_extfree_item.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)


diff --git a/fs/xfs/xfs_extfree_item.c b/fs/xfs/xfs_extfree_item.c
index b5710b7fc263..b1c004016709 100644
--- a/fs/xfs/xfs_extfree_item.c
+++ b/fs/xfs/xfs_extfree_item.c
@@ -584,14 +584,14 @@ xfs_efi_validate_ext(
 	struct xfs_mount		*mp,
 	struct xfs_extent		*extp)
 {
-	xfs_fsblock_t			startblock_fsb;
+	xfs_fsblock_t			end;
 
-	startblock_fsb = XFS_BB_TO_FSB(mp,
-			   XFS_FSB_TO_DADDR(mp, extp->ext_start));
-	if (startblock_fsb == 0 ||
-	    extp->ext_len == 0 ||
-	    startblock_fsb >= mp->m_sb.sb_dblocks ||
-	    extp->ext_len >= mp->m_sb.sb_agblocks)
+	if (extp->ext_start + extp->ext_len <= extp->ext_start)
+		return false;
+
+	end = extp->ext_start + extp->ext_len - 1;
+	if (!xfs_verify_fsbno(mp, extp->ext_start) ||
+	    !xfs_verify_fsbno(mp, end))
 		return false;
 
 	return true;

Re: [PATCH 08/10] xfs: improve the code that checks recovered extent-free intent items

[Christoph Hellwig]

Looks good modulo the end nitpick:

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 09/10] xfs: validate feature support when recovering rmap/refcount/bmap intents

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

The bmap, rmap, and refcount log intent items were added to support the
rmap and reflink features.  Because these features come with changes to
the ondisk format, the log items aren't tied to a log incompat flags.

However, the log recovery routines don't actually check for those
feature flags.  The kernel has no business replayng an intent item for a
feature that isn't enabled, so check that as part of recovered log item
validation.  (Note that kernels pre-dating rmap and reflink will fail
the mount on the unknown log item type code.)

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_bmap_item.c     |    4 ++++
 fs/xfs/xfs_refcount_item.c |    3 +++
 fs/xfs/xfs_rmap_item.c     |    3 +++
 3 files changed, 10 insertions(+)


diff --git a/fs/xfs/xfs_bmap_item.c b/fs/xfs/xfs_bmap_item.c
index 19f89a6b65a1..f36005c999b2 100644
--- a/fs/xfs/xfs_bmap_item.c
+++ b/fs/xfs/xfs_bmap_item.c
@@ -426,6 +426,10 @@ xfs_bui_validate(
 	struct xfs_map_extent		*bmap;
 	xfs_fsblock_t			end;
 
+	if (!xfs_sb_version_hasrmapbt(&mp->m_sb) &&
+	    !xfs_sb_version_hasreflink(&mp->m_sb))
+		return false;
+
 	/* Only one mapping operation per BUI... */
 	if (buip->bui_format.bui_nextents != XFS_BUI_MAX_FAST_EXTENTS)
 		return false;
diff --git a/fs/xfs/xfs_refcount_item.c b/fs/xfs/xfs_refcount_item.c
index 20e5c22bb754..2017108b37a1 100644
--- a/fs/xfs/xfs_refcount_item.c
+++ b/fs/xfs/xfs_refcount_item.c
@@ -425,6 +425,9 @@ xfs_cui_validate_phys(
 {
 	xfs_fsblock_t			end;
 
+	if (!xfs_sb_version_hasreflink(&mp->m_sb))
+		return false;
+
 	if (refc->pe_flags & ~XFS_REFCOUNT_EXTENT_FLAGS)
 		return false;
 
diff --git a/fs/xfs/xfs_rmap_item.c b/fs/xfs/xfs_rmap_item.c
index 2779cbee8fa8..13871882ffb6 100644
--- a/fs/xfs/xfs_rmap_item.c
+++ b/fs/xfs/xfs_rmap_item.c
@@ -468,6 +468,9 @@ xfs_rui_validate_map(
 {
 	xfs_fsblock_t			end;
 
+	if (!xfs_sb_version_hasrmapbt(&mp->m_sb))
+		return false;
+
 	if (rmap->me_flags & ~XFS_RMAP_EXTENT_FLAGS)
 		return false;
 

Re: [PATCH 09/10] xfs: validate feature support when recovering rmap/refcount/bmap intents

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:38:34PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> The bmap, rmap, and refcount log intent items were added to support the
> rmap and reflink features.  Because these features come with changes to
> the ondisk format, the log items aren't tied to a log incompat flags.
> 
> However, the log recovery routines don't actually check for those
> feature flags.  The kernel has no business replayng an intent item for a
> feature that isn't enabled, so check that as part of recovered log item
> validation.  (Note that kernels pre-dating rmap and reflink will fail
> the mount on the unknown log item type code.)
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>

[PATCH 10/10] xfs: trace log intent item recovery failures

[Darrick J. Wong]

From: Darrick J. Wong <darrick.wong@oracle.com>

Add a trace point so that we can capture when a recovered log intent
item fails to recover.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
---
 fs/xfs/xfs_log_recover.c |    5 ++++-
 fs/xfs/xfs_trace.h       |   19 +++++++++++++++++++
 2 files changed, 23 insertions(+), 1 deletion(-)


diff --git a/fs/xfs/xfs_log_recover.c b/fs/xfs/xfs_log_recover.c
index 87886b7f77da..ed92c72976c9 100644
--- a/fs/xfs/xfs_log_recover.c
+++ b/fs/xfs/xfs_log_recover.c
@@ -2559,8 +2559,11 @@ xlog_recover_process_intents(
 		spin_unlock(&ailp->ail_lock);
 		error = lip->li_ops->iop_recover(lip, &capture_list);
 		spin_lock(&ailp->ail_lock);
-		if (error)
+		if (error) {
+			trace_xfs_error_return(log->l_mp, error,
+					lip->li_ops->iop_recover);
 			break;
+		}
 	}
 
 	xfs_trans_ail_cursor_done(&cur);
diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h
index 86951652d3ed..99383b1acd49 100644
--- a/fs/xfs/xfs_trace.h
+++ b/fs/xfs/xfs_trace.h
@@ -103,6 +103,25 @@ DEFINE_ATTR_LIST_EVENT(xfs_attr_list_notfound);
 DEFINE_ATTR_LIST_EVENT(xfs_attr_leaf_list);
 DEFINE_ATTR_LIST_EVENT(xfs_attr_node_list);
 
+TRACE_EVENT(xfs_error_return,
+	TP_PROTO(struct xfs_mount *mp, int error, void *caller_ip),
+	TP_ARGS(mp, error, caller_ip),
+	TP_STRUCT__entry(
+		__field(dev_t, dev)
+		__field(int, error)
+		__field(void *, caller_ip)
+	),
+	TP_fast_assign(
+		__entry->dev = mp->m_super->s_dev;
+		__entry->error = error;
+		__entry->caller_ip = caller_ip;
+	),
+	TP_printk("dev %d:%d error %d caller %pS",
+		  MAJOR(__entry->dev), MINOR(__entry->dev),
+		  __entry->error, __entry->caller_ip)
+
+);
+
 DECLARE_EVENT_CLASS(xfs_perag_class,
 	TP_PROTO(struct xfs_mount *mp, xfs_agnumber_t agno, int refcount,
 		 unsigned long caller_ip),

Re: [PATCH 10/10] xfs: trace log intent item recovery failures

[Christoph Hellwig]

On Mon, Nov 30, 2020 at 07:38:41PM -0800, Darrick J. Wong wrote:
> From: Darrick J. Wong <darrick.wong@oracle.com>
> 
> Add a trace point so that we can capture when a recovered log intent
> item fails to recover.
> 
> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>

Looks good,

Reviewed-by: Christoph Hellwig <hch@lst.de>