From 6b69e485894b355b333bd286f0f0958e41d8754a Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Wed, 12 May 2021 12:49:19 -0700 Subject: xfs: standardize extent size hint validation While chasing a bug involving invalid extent size hints being propagated into newly created realtime files, I noticed that the xfs_ioctl_setattr checks for the extent size hints weren't the same as the ones now encoded in libxfs and used for validation in repair and mkfs. Because the checks in libxfs are more stringent than the ones in the ioctl, it's possible for a live system to set inode flags that immediately result in corruption warnings. Specifically, it's possible to set an extent size hint on an rtinherit directory without checking if the hint is aligned to the realtime extent size, which makes no sense since that combination is used only to seed new realtime files. Replace the open-coded and inadequate checks with the libxfs verifier versions and update the code comments a bit. Signed-off-by: Darrick J. Wong Reviewed-by: Brian Foster Reviewed-by: Christoph Hellwig --- fs/xfs/xfs_ioctl.c | 90 +++++++++++++----------------------------------------- 1 file changed, 21 insertions(+), 69 deletions(-) (limited to 'fs/xfs/xfs_ioctl.c') diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 3925bfcb2365..6407921aca96 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1267,20 +1267,8 @@ out_error: } /* - * extent size hint validation is somewhat cumbersome. Rules are: - * - * 1. extent size hint is only valid for directories and regular files - * 2. FS_XFLAG_EXTSIZE is only valid for regular files - * 3. FS_XFLAG_EXTSZINHERIT is only valid for directories. - * 4. can only be changed on regular files if no extents are allocated - * 5. can be changed on directories at any time - * 6. extsize hint of 0 turns off hints, clears inode flags. - * 7. Extent size must be a multiple of the appropriate block size. - * 8. for non-realtime files, the extent size hint must be limited - * to half the AG size to avoid alignment extending the extent beyond the - * limits of the AG. - * - * Please keep this function in sync with xfs_scrub_inode_extsize. + * Validate a proposed extent size hint. For regular files, the hint can only + * be changed if no extents are allocated. */ static int xfs_ioctl_setattr_check_extsize( @@ -1288,86 +1276,50 @@ xfs_ioctl_setattr_check_extsize( struct fileattr *fa) { struct xfs_mount *mp = ip->i_mount; - xfs_extlen_t size; - xfs_fsblock_t extsize_fsb; + xfs_failaddr_t failaddr; + uint16_t new_diflags; if (!fa->fsx_valid) return 0; if (S_ISREG(VFS_I(ip)->i_mode) && ip->i_df.if_nextents && - ((ip->i_extsize << mp->m_sb.sb_blocklog) != fa->fsx_extsize)) + XFS_FSB_TO_B(mp, ip->i_extsize) != fa->fsx_extsize) return -EINVAL; - if (fa->fsx_extsize == 0) - return 0; - - extsize_fsb = XFS_B_TO_FSB(mp, fa->fsx_extsize); - if (extsize_fsb > MAXEXTLEN) + if (fa->fsx_extsize & mp->m_blockmask) return -EINVAL; - if (XFS_IS_REALTIME_INODE(ip) || - (fa->fsx_xflags & FS_XFLAG_REALTIME)) { - size = mp->m_sb.sb_rextsize << mp->m_sb.sb_blocklog; - } else { - size = mp->m_sb.sb_blocksize; - if (extsize_fsb > mp->m_sb.sb_agblocks / 2) - return -EINVAL; - } - - if (fa->fsx_extsize % size) - return -EINVAL; + new_diflags = xfs_flags2diflags(ip, fa->fsx_xflags); - return 0; + failaddr = xfs_inode_validate_extsize(ip->i_mount, + XFS_B_TO_FSB(mp, fa->fsx_extsize), + VFS_I(ip)->i_mode, new_diflags); + return failaddr != NULL ? -EINVAL : 0; } -/* - * CoW extent size hint validation rules are: - * - * 1. CoW extent size hint can only be set if reflink is enabled on the fs. - * The inode does not have to have any shared blocks, but it must be a v3. - * 2. FS_XFLAG_COWEXTSIZE is only valid for directories and regular files; - * for a directory, the hint is propagated to new files. - * 3. Can be changed on files & directories at any time. - * 4. CoW extsize hint of 0 turns off hints, clears inode flags. - * 5. Extent size must be a multiple of the appropriate block size. - * 6. The extent size hint must be limited to half the AG size to avoid - * alignment extending the extent beyond the limits of the AG. - * - * Please keep this function in sync with xfs_scrub_inode_cowextsize. - */ static int xfs_ioctl_setattr_check_cowextsize( struct xfs_inode *ip, struct fileattr *fa) { struct xfs_mount *mp = ip->i_mount; - xfs_extlen_t size; - xfs_fsblock_t cowextsize_fsb; + xfs_failaddr_t failaddr; + uint64_t new_diflags2; + uint16_t new_diflags; if (!fa->fsx_valid) return 0; - if (!(fa->fsx_xflags & FS_XFLAG_COWEXTSIZE)) - return 0; - - if (!xfs_sb_version_hasreflink(&ip->i_mount->m_sb)) - return -EINVAL; - - if (fa->fsx_cowextsize == 0) - return 0; - - cowextsize_fsb = XFS_B_TO_FSB(mp, fa->fsx_cowextsize); - if (cowextsize_fsb > MAXEXTLEN) - return -EINVAL; - - size = mp->m_sb.sb_blocksize; - if (cowextsize_fsb > mp->m_sb.sb_agblocks / 2) + if (fa->fsx_cowextsize & mp->m_blockmask) return -EINVAL; - if (fa->fsx_cowextsize % size) - return -EINVAL; + new_diflags = xfs_flags2diflags(ip, fa->fsx_xflags); + new_diflags2 = xfs_flags2diflags2(ip, fa->fsx_xflags); - return 0; + failaddr = xfs_inode_validate_cowextsize(ip->i_mount, + XFS_B_TO_FSB(mp, fa->fsx_cowextsize), + VFS_I(ip)->i_mode, new_diflags, new_diflags2); + return failaddr != NULL ? -EINVAL : 0; } static int -- cgit v1.2.3