From 005e716151c52c29566b5c9aa31f9e814693bd8d Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Thu, 15 Aug 2024 11:49:33 -0700 Subject: [PATCH] xfs: apply rt extent alignment constraints to CoW extsize hint The copy-on-write extent size hint is subject to the same alignment constraints as the regular extent size hint. Since we're in the process of adding reflink (and therefore CoW) to the realtime device, we must apply the same scattered rextsize alignment validation strategies to both hints to deal with the possibility of rextsize changing. Therefore, fix the inode validator to perform rextsize alignment checks on regular realtime files, and to remove misaligned directory hints. Signed-off-by: Darrick J. Wong --- fs/xfs/libxfs/xfs_inode_buf.c | 25 ++++++++++++++++++++----- fs/xfs/xfs_inode_item.c | 14 ++++++++++++++ fs/xfs/xfs_ioctl.c | 17 +++++++++++++++-- 3 files changed, 49 insertions(+), 7 deletions(-) diff --git a/fs/xfs/libxfs/xfs_inode_buf.c b/fs/xfs/libxfs/xfs_inode_buf.c index 1cc262201507..dcb30ad521f0 100644 --- a/fs/xfs/libxfs/xfs_inode_buf.c +++ b/fs/xfs/libxfs/xfs_inode_buf.c @@ -912,11 +912,29 @@ xfs_inode_validate_cowextsize( bool rt_flag; bool hint_flag; uint32_t cowextsize_bytes; + uint32_t blocksize_bytes; rt_flag = (flags & XFS_DIFLAG_REALTIME); hint_flag = (flags2 & XFS_DIFLAG2_COWEXTSIZE); cowextsize_bytes = XFS_FSB_TO_B(mp, cowextsize); + /* + * Similar to extent size hints, a directory can be configured to + * propagate realtime status and a CoW extent size hint to newly + * created files even if there is no realtime device, and the hints on + * disk can become misaligned if the sysadmin changes the rt extent + * size while adding the realtime device. + * + * Therefore, we can only enforce the rextsize alignment check against + * regular realtime files, and rely on callers to decide when alignment + * checks are appropriate, and fix things up as needed. + */ + + if (rt_flag) + blocksize_bytes = XFS_FSB_TO_B(mp, mp->m_sb.sb_rextsize); + else + blocksize_bytes = mp->m_sb.sb_blocksize; + if (hint_flag && !xfs_has_reflink(mp)) return __this_address; @@ -930,16 +948,13 @@ xfs_inode_validate_cowextsize( if (mode && !hint_flag && cowextsize != 0) return __this_address; - if (hint_flag && rt_flag) - return __this_address; - - if (cowextsize_bytes % mp->m_sb.sb_blocksize) + if (cowextsize_bytes % blocksize_bytes) return __this_address; if (cowextsize > XFS_MAX_BMBT_EXTLEN) return __this_address; - if (cowextsize > mp->m_sb.sb_agblocks / 2) + if (!rt_flag && cowextsize > mp->m_sb.sb_agblocks / 2) return __this_address; return NULL; diff --git a/fs/xfs/xfs_inode_item.c b/fs/xfs/xfs_inode_item.c index 1275e8a35ea4..5338c7fa12c9 100644 --- a/fs/xfs/xfs_inode_item.c +++ b/fs/xfs/xfs_inode_item.c @@ -157,6 +157,20 @@ xfs_inode_item_precommit( if (flags & XFS_ILOG_IVERSION) flags = ((flags & ~XFS_ILOG_IVERSION) | XFS_ILOG_CORE); + /* + * Inode verifiers do not check that the CoW extent size hint is an + * integer multiple of the rt extent size on a directory with both + * rtinherit and cowextsize flags set. If we're logging a directory + * that is misconfigured in this way, clear the hint. + */ + if ((ip->i_diflags & XFS_DIFLAG_RTINHERIT) && + (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) && + xfs_extlen_to_rtxmod(ip->i_mount, ip->i_cowextsize) > 0) { + ip->i_diflags2 &= ~XFS_DIFLAG2_COWEXTSIZE; + ip->i_cowextsize = 0; + flags |= XFS_ILOG_CORE; + } + if (!iip->ili_item.li_buf) { struct xfs_buf *bp; int error; diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 0ed2af0b1ff7..d621b270704c 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -467,8 +467,21 @@ xfs_fill_fsxattr( } } - if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) - fa->fsx_cowextsize = XFS_FSB_TO_B(mp, ip->i_cowextsize); + if (ip->i_diflags2 & XFS_DIFLAG2_COWEXTSIZE) { + /* + * Don't let a misaligned CoW extent size hint on a directory + * escape to userspace if it won't pass the setattr checks + * later. + */ + if ((ip->i_diflags & XFS_DIFLAG_RTINHERIT) && + ip->i_cowextsize % mp->m_sb.sb_rextsize > 0) { + fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE; + fa->fsx_cowextsize = 0; + } else { + fa->fsx_cowextsize = XFS_FSB_TO_B(mp, ip->i_cowextsize); + } + } + fa->fsx_projid = ip->i_projid; if (ifp && !xfs_need_iread_extents(ifp)) fa->fsx_nextents = xfs_iext_count(ifp); -- 2.50.1