[PATCH 3/9] xfs: validate attr leaf buffer owners

Darrick J. Wong
2023-12-31T20:33:22Z

Create a leaf block header checking function to validate the owner field
of xattr leaf blocks.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
fs/xfs/libxfs/xfs_attr.c | 10 ++++---
fs/xfs/libxfs/xfs_attr_leaf.c | 55 ++++++++++++++++++++++++++++++++++-------
fs/xfs/libxfs/xfs_attr_leaf.h | 4 ++-
fs/xfs/libxfs/xfs_da_btree.c | 42 +++++++++++++++++++++++++++++++
fs/xfs/libxfs/xfs_da_btree.h | 1 +
fs/xfs/libxfs/xfs_swapext.c | 3 +-
fs/xfs/scrub/dabtree.c | 7 +++++
fs/xfs/xfs_attr_list.c | 25 ++++++++++++++++---
8 files changed, 128 insertions(+), 19 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c
index fa49c795f4074..1e94e933d7682 100644
--- a/fs/xfs/libxfs/xfs_attr.c
+++ b/fs/xfs/libxfs/xfs_attr.c
@@ -647,8 +647,8 @@ xfs_attr_leaf_remove_attr(
int forkoff;
int error;

- error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno,
- &bp);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner,
+ args->blkno, &bp);
if (error)
return error;

@@ -679,7 +679,7 @@ xfs_attr_leaf_shrink(
if (!xfs_attr_is_leaf(dp))
return 0;

- error = xfs_attr3_leaf_read(args->trans, args->dp, 0, &bp);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 0, &bp);
if (error)
return error;

@@ -1160,7 +1160,7 @@ xfs_attr_leaf_try_add(
struct xfs_buf *bp;
int error;

- error = xfs_attr3_leaf_read(args->trans, args->dp, 0, &bp);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 0, &bp);
if (error)
return error;

@@ -1208,7 +1208,7 @@ xfs_attr_leaf_hasname(
{
int error = 0;

- error = xfs_attr3_leaf_read(args->trans, args->dp, 0, bp);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner, 0, bp);
if (error)
return error;

diff --git a/fs/xfs/libxfs/xfs_attr_leaf.c b/fs/xfs/libxfs/xfs_attr_leaf.c
index 01f93122f4286..3face870b4dac 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.c
+++ b/fs/xfs/libxfs/xfs_attr_leaf.c
@@ -388,6 +388,26 @@ xfs_attr3_leaf_verify(
return NULL;
}

+xfs_failaddr_t
+xfs_attr3_leaf_header_check(
+ struct xfs_buf *bp,
+ xfs_ino_t owner)
+{
+ struct xfs_mount *mp = bp->b_mount;
+
+ if (xfs_has_crc(mp)) {
+ struct xfs_attr3_leafblock *hdr3 = bp->b_addr;
+
+ ASSERT(hdr3->hdr.info.hdr.magic ==
+ cpu_to_be16(XFS_ATTR3_LEAF_MAGIC));
+
+ if (be64_to_cpu(hdr3->hdr.info.owner) != owner)
+ return __this_address;
+ }
+
+ return NULL;
+}
+
static void
xfs_attr3_leaf_write_verify(
struct xfs_buf *bp)
@@ -448,16 +468,30 @@ int
xfs_attr3_leaf_read(
struct xfs_trans *tp,
struct xfs_inode *dp,
+ xfs_ino_t owner,
xfs_dablk_t bno,
struct xfs_buf **bpp)
{
+ xfs_failaddr_t fa;
int err;

err = xfs_da_read_buf(tp, dp, bno, 0, bpp, XFS_ATTR_FORK,
&xfs_attr3_leaf_buf_ops);
- if (!err && tp && *bpp)
+ if (err || !(*bpp))
+ return err;
+
+ fa = xfs_attr3_leaf_header_check(*bpp, owner);
+ if (fa) {
+ __xfs_buf_mark_corrupt(*bpp, fa);
+ xfs_trans_brelse(tp, *bpp);
+ *bpp = NULL;
+ xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);
+ return -EFSCORRUPTED;
+ }
+
+ if (tp)
xfs_trans_buf_set_type(tp, *bpp, XFS_BLFT_ATTR_LEAF_BUF);
- return err;
+ return 0;
}

/*========================================================================
@@ -1232,7 +1266,7 @@ xfs_attr3_leaf_to_node(
error = xfs_da_grow_inode(args, &blkno);
if (error)
goto out;
- error = xfs_attr3_leaf_read(args->trans, dp, 0, &bp1);
+ error = xfs_attr3_leaf_read(args->trans, dp, args->owner, 0, &bp1);
if (error)
goto out;

@@ -2067,7 +2101,7 @@ xfs_attr3_leaf_toosmall(
if (blkno == 0)
continue;
error = xfs_attr3_leaf_read(state->args->trans, state->args->dp,
- blkno, &bp);
+ state->args->owner, blkno, &bp);
if (error)
return error;

@@ -2788,7 +2822,8 @@ xfs_attr3_leaf_clearflag(
/*
* Set up the operation.
*/
- error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner,
+ args->blkno, &bp);
if (error)
return error;

@@ -2852,7 +2887,8 @@ xfs_attr3_leaf_setflag(
/*
* Set up the operation.
*/
- error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner,
+ args->blkno, &bp);
if (error)
return error;

@@ -2911,7 +2947,8 @@ xfs_attr3_leaf_flipflags(
/*
* Read the block containing the "old" attr
*/
- error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno, &bp1);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner,
+ args->blkno, &bp1);
if (error)
return error;

@@ -2919,8 +2956,8 @@ xfs_attr3_leaf_flipflags(
* Read the block containing the "new" attr, if it is different
*/
if (args->blkno2 != args->blkno) {
- error = xfs_attr3_leaf_read(args->trans, args->dp, args->blkno2,
- &bp2);
+ error = xfs_attr3_leaf_read(args->trans, args->dp, args->owner,
+ args->blkno2, &bp2);
if (error)
return error;
} else {
diff --git a/fs/xfs/libxfs/xfs_attr_leaf.h b/fs/xfs/libxfs/xfs_attr_leaf.h
index ce6743463c868..70edddedd1ad3 100644
--- a/fs/xfs/libxfs/xfs_attr_leaf.h
+++ b/fs/xfs/libxfs/xfs_attr_leaf.h
@@ -101,12 +101,14 @@ int xfs_attr_leaf_order(struct xfs_buf *leaf1_bp,
struct xfs_buf *leaf2_bp);
int xfs_attr_leaf_newentsize(struct xfs_da_args *args, int *local);
int xfs_attr3_leaf_read(struct xfs_trans *tp, struct xfs_inode *dp,
- xfs_dablk_t bno, struct xfs_buf **bpp);
+ xfs_ino_t owner, xfs_dablk_t bno, struct xfs_buf **bpp);
void xfs_attr3_leaf_hdr_from_disk(struct xfs_da_geometry *geo,
struct xfs_attr3_icleaf_hdr *to,
struct xfs_attr_leafblock *from);
void xfs_attr3_leaf_hdr_to_disk(struct xfs_da_geometry *geo,
struct xfs_attr_leafblock *to,
struct xfs_attr3_icleaf_hdr *from);
+xfs_failaddr_t xfs_attr3_leaf_header_check(struct xfs_buf *bp,
+ xfs_ino_t owner);

#endif /* __XFS_ATTR_LEAF_H__ */
diff --git a/fs/xfs/libxfs/xfs_da_btree.c b/fs/xfs/libxfs/xfs_da_btree.c
index a69d04ed74935..a7782055db6cd 100644
--- a/fs/xfs/libxfs/xfs_da_btree.c
+++ b/fs/xfs/libxfs/xfs_da_btree.c
@@ -251,6 +251,25 @@ xfs_da3_node_verify(
return NULL;
}

+xfs_failaddr_t
+xfs_da3_header_check(
+ struct xfs_buf *bp,
+ xfs_ino_t owner)
+{
+ struct xfs_mount *mp = bp->b_mount;
+ struct xfs_da_blkinfo *hdr = bp->b_addr;
+
+ if (!xfs_has_crc(mp))
+ return NULL;
+
+ switch (hdr->magic) {
+ case cpu_to_be16(XFS_ATTR3_LEAF_MAGIC):
+ return xfs_attr3_leaf_header_check(bp, owner);
+ }
+
+ return NULL;
+}
+
static void
xfs_da3_node_write_verify(
struct xfs_buf *bp)
@@ -1590,6 +1609,7 @@ xfs_da3_node_lookup_int(
struct xfs_da_node_entry *btree;
struct xfs_da3_icnode_hdr nodehdr;
struct xfs_da_args *args;
+ xfs_failaddr_t fa;
xfs_dablk_t blkno;
xfs_dahash_t hashval;
xfs_dahash_t btreehashval;
@@ -1628,6 +1648,12 @@ xfs_da3_node_lookup_int(

if (magic == XFS_ATTR_LEAF_MAGIC ||
magic == XFS_ATTR3_LEAF_MAGIC) {
+ fa = xfs_attr3_leaf_header_check(blk->bp, args->owner);
+ if (fa) {
+ __xfs_buf_mark_corrupt(blk->bp, fa);
+ xfs_da_mark_sick(args);
+ return -EFSCORRUPTED;
+ }
blk->magic = XFS_ATTR_LEAF_MAGIC;
blk->hashval = xfs_attr_leaf_lasthash(blk->bp, NULL);
break;
@@ -1995,6 +2021,7 @@ xfs_da3_path_shift(
struct xfs_da_node_entry *btree;
struct xfs_da3_icnode_hdr nodehdr;
struct xfs_buf *bp;
+ xfs_failaddr_t fa;
xfs_dablk_t blkno = 0;
int level;
int error;
@@ -2086,6 +2113,12 @@ xfs_da3_path_shift(
break;
case XFS_ATTR_LEAF_MAGIC:
case XFS_ATTR3_LEAF_MAGIC:
+ fa = xfs_attr3_leaf_header_check(blk->bp, args->owner);
+ if (fa) {
+ __xfs_buf_mark_corrupt(blk->bp, fa);
+ xfs_da_mark_sick(args);
+ return -EFSCORRUPTED;
+ }
blk->magic = XFS_ATTR_LEAF_MAGIC;
ASSERT(level == path->active-1);
blk->index = 0;
@@ -2288,6 +2321,7 @@ xfs_da3_swap_lastblock(
struct xfs_buf *last_buf;
struct xfs_buf *sib_buf;
struct xfs_buf *par_buf;
+ xfs_failaddr_t fa;
xfs_dahash_t dead_hash;
xfs_fileoff_t lastoff;
xfs_dablk_t dead_blkno;
@@ -2324,6 +2358,14 @@ xfs_da3_swap_lastblock(
error = xfs_da3_node_read(tp, dp, last_blkno, &last_buf, w);
if (error)
return error;
+ fa = xfs_da3_header_check(last_buf, args->owner);
+ if (fa) {
+ __xfs_buf_mark_corrupt(last_buf, fa);
+ xfs_trans_brelse(tp, last_buf);
+ xfs_da_mark_sick(args);
+ return -EFSCORRUPTED;
+ }
+
/*
* Copy the last block into the dead buffer and log it.
*/
diff --git a/fs/xfs/libxfs/xfs_da_btree.h b/fs/xfs/libxfs/xfs_da_btree.h
index 7fb13f26edaa7..99618e0c8a72b 100644
--- a/fs/xfs/libxfs/xfs_da_btree.h
+++ b/fs/xfs/libxfs/xfs_da_btree.h
@@ -236,6 +236,7 @@ void xfs_da3_node_hdr_from_disk(struct xfs_mount *mp,
struct xfs_da3_icnode_hdr *to, struct xfs_da_intnode *from);
void xfs_da3_node_hdr_to_disk(struct xfs_mount *mp,
struct xfs_da_intnode *to, struct xfs_da3_icnode_hdr *from);
+xfs_failaddr_t xfs_da3_header_check(struct xfs_buf *bp, xfs_ino_t owner);

extern struct kmem_cache *xfs_da_state_cache;

diff --git a/fs/xfs/libxfs/xfs_swapext.c b/fs/xfs/libxfs/xfs_swapext.c
index ced2365fa7b59..0446376365ec7 100644
--- a/fs/xfs/libxfs/xfs_swapext.c
+++ b/fs/xfs/libxfs/xfs_swapext.c
@@ -535,7 +535,8 @@ xfs_swapext_attr_to_sf(
if (!xfs_attr_is_leaf(sxi->sxi_ip2))
return 0;

- error = xfs_attr3_leaf_read(tp, sxi->sxi_ip2, 0, &bp);
+ error = xfs_attr3_leaf_read(tp, sxi->sxi_ip2, sxi->sxi_ip2->i_ino, 0,
+ &bp);
if (error)
return error;

diff --git a/fs/xfs/scrub/dabtree.c b/fs/xfs/scrub/dabtree.c
index fa6385a99ac4e..c71254088dffe 100644
--- a/fs/xfs/scrub/dabtree.c
+++ b/fs/xfs/scrub/dabtree.c
@@ -320,6 +320,7 @@ xchk_da_btree_block(
struct xfs_da3_blkinfo *hdr3;
struct xfs_da_args *dargs = &ds->dargs;
struct xfs_inode *ip = ds->dargs.dp;
+ xfs_failaddr_t fa;
xfs_ino_t owner;
int *pmaxrecs;
struct xfs_da3_icnode_hdr nodehdr;
@@ -442,6 +443,12 @@ xchk_da_btree_block(
goto out_freebp;
}

+ fa = xfs_da3_header_check(blk->bp, dargs->owner);
+ if (fa) {
+ xchk_da_set_corrupt(ds, level);
+ goto out_freebp;
+ }
+
/*
* If we've been handed a block that is below the dabtree root, does
* its hashval match what the parent block expected to see?
diff --git a/fs/xfs/xfs_attr_list.c b/fs/xfs/xfs_attr_list.c
index dcfa8e8e146a3..2954ed7cfaf43 100644
--- a/fs/xfs/xfs_attr_list.c
+++ b/fs/xfs/xfs_attr_list.c
@@ -215,6 +215,7 @@ xfs_attr_node_list_lookup(
struct xfs_mount *mp = dp->i_mount;
struct xfs_trans *tp = context->tp;
struct xfs_buf *bp;
+ xfs_failaddr_t fa;
int i;
int error = 0;
unsigned int expected_level = 0;
@@ -274,6 +275,12 @@ xfs_attr_node_list_lookup(
}
}

+ fa = xfs_attr3_leaf_header_check(bp, dp->i_ino);
+ if (fa) {
+ __xfs_buf_mark_corrupt(bp, fa);
+ goto out_releasebuf;
+ }
+
if (expected_level != 0)
goto out_corruptbuf;

@@ -282,6 +289,7 @@ xfs_attr_node_list_lookup(

out_corruptbuf:
xfs_buf_mark_corrupt(bp);
+out_releasebuf:
xfs_trans_brelse(tp, bp);
xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);
return -EFSCORRUPTED;
@@ -298,6 +306,7 @@ xfs_attr_node_list(
struct xfs_buf *bp;
struct xfs_inode *dp = context->dp;
struct xfs_mount *mp = dp->i_mount;
+ xfs_failaddr_t fa;
int error = 0;

trace_xfs_attr_node_list(context);
@@ -331,6 +340,15 @@ xfs_attr_node_list(
case XFS_ATTR_LEAF_MAGIC:
case XFS_ATTR3_LEAF_MAGIC:
leaf = bp->b_addr;
+ fa = xfs_attr3_leaf_header_check(bp,
+ dp->i_ino);
+ if (fa) {
+ __xfs_buf_mark_corrupt(bp, fa);
+ xfs_trans_brelse(context->tp, bp);
+ xfs_dirattr_mark_sick(dp, XFS_ATTR_FORK);
+ bp = NULL;
+ break;
+ }
xfs_attr3_leaf_hdr_from_disk(mp->m_attr_geo,
&leafhdr, leaf);
entries = xfs_attr3_leaf_entryp(leaf);
@@ -381,8 +399,8 @@ xfs_attr_node_list(
break;
cursor->blkno = leafhdr.forw;
xfs_trans_brelse(context->tp, bp);
- error = xfs_attr3_leaf_read(context->tp, dp, cursor->blkno,
- &bp);
+ error = xfs_attr3_leaf_read(context->tp, dp, dp->i_ino,
+ cursor->blkno, &bp);
if (error)
return error;
}
@@ -502,7 +520,8 @@ xfs_attr_leaf_list(
trace_xfs_attr_leaf_list(context);

context->cursor.blkno = 0;
- error = xfs_attr3_leaf_read(context->tp, context->dp, 0, &bp);
+ error = xfs_attr3_leaf_read(context->tp, context->dp,
+ context->dp->i_ino, 0, &bp);
if (error)
return error;