From 3a19bb147c72d2e9b77137bf5130b9cfb50a5eef Mon Sep 17 00:00:00 2001 From: Chandan Babu R Date: Fri, 22 Jan 2021 16:48:13 -0800 Subject: [PATCH] xfs: Check for extent overflow when adding/removing xattrs Adding/removing an xattr can cause XFS_DA_NODE_MAXDEPTH extents to be added. One extra extent for dabtree in case a local attr is large enough to cause a double split. It can also cause extent count to increase proportional to the size of a remote xattr's value. Reviewed-by: Darrick J. Wong Reviewed-by: Christoph Hellwig Reviewed-by: Allison Henderson Signed-off-by: Chandan Babu R Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_attr.c | 13 +++++++++++++ fs/xfs/libxfs/xfs_inode_fork.h | 10 ++++++++++ 2 files changed, 23 insertions(+) diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c index fd8e6418a0d3..be51e7068dcd 100644 --- a/fs/xfs/libxfs/xfs_attr.c +++ b/fs/xfs/libxfs/xfs_attr.c @@ -396,6 +396,7 @@ xfs_attr_set( struct xfs_trans_res tres; bool rsvd = (args->attr_filter & XFS_ATTR_ROOT); int error, local; + int rmt_blks = 0; unsigned int total; if (XFS_FORCED_SHUTDOWN(dp->i_mount)) @@ -442,11 +443,15 @@ xfs_attr_set( tres.tr_logcount = XFS_ATTRSET_LOG_COUNT; tres.tr_logflags = XFS_TRANS_PERM_LOG_RES; total = args->total; + + if (!local) + rmt_blks = xfs_attr3_rmt_blocks(mp, args->valuelen); } else { XFS_STATS_INC(mp, xs_attr_remove); tres = M_RES(mp)->tr_attrrm; total = XFS_ATTRRM_SPACE_RES(mp); + rmt_blks = xfs_attr3_rmt_blocks(mp, XFS_XATTR_SIZE_MAX); } /* @@ -460,6 +465,14 @@ xfs_attr_set( xfs_ilock(dp, XFS_ILOCK_EXCL); xfs_trans_ijoin(args->trans, dp, 0); + + if (args->value || xfs_inode_hasattr(dp)) { + error = xfs_iext_count_may_overflow(dp, XFS_ATTR_FORK, + XFS_IEXT_ATTR_MANIP_CNT(rmt_blks)); + if (error) + goto out_trans_cancel; + } + if (args->value) { unsigned int quota_flags = XFS_QMOPT_RES_REGBLKS; diff --git a/fs/xfs/libxfs/xfs_inode_fork.h b/fs/xfs/libxfs/xfs_inode_fork.h index ea1a9dd8a763..8d89838e23f8 100644 --- a/fs/xfs/libxfs/xfs_inode_fork.h +++ b/fs/xfs/libxfs/xfs_inode_fork.h @@ -60,6 +60,16 @@ struct xfs_ifork { #define XFS_IEXT_DIR_MANIP_CNT(mp) \ ((XFS_DA_NODE_MAXDEPTH + 1 + 1) * (mp)->m_dir_geo->fsbcount) +/* + * Adding/removing an xattr can cause XFS_DA_NODE_MAXDEPTH extents to + * be added. One extra extent for dabtree in case a local attr is + * large enough to cause a double split. It can also cause extent + * count to increase proportional to the size of a remote xattr's + * value. + */ +#define XFS_IEXT_ATTR_MANIP_CNT(rmt_blks) \ + (XFS_DA_NODE_MAXDEPTH + max(1, rmt_blks)) + /* * Fork handling. */ -- 2.25.1