From 4d1b97f9ce7c0d2af2bb85b12d48e6902172a28e Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Fri, 7 Jan 2022 17:45:51 -0800 Subject: xfs: kill the XFS_IOC_{ALLOC,FREE}SP* ioctls According to the glibc compat header for Irix 4, these ioctls originated in April 1991 as a (somewhat clunky) way to preallocate space at the end of a file on an EFS filesystem. XFS, which was released in Irix 5.3 in December 1993, picked up these ioctls to maintain compatibility and they were ported to Linux in the early 2000s. Recently it was pointed out to me they still lurk in the kernel, even though the Linux fallocate syscall supplanted the functionality a long time ago. fstests doesn't seem to include any real functional or stress tests for these ioctls, which means that the code quality is ... very questionable. Most notably, it was a stale disk block exposure vector for 21 years and nobody noticed or complained. As mature programmers say, "If you're not testing it, it's broken." Given all that, let's withdraw these ioctls from the XFS userspace API. Normally we'd set a long deprecation process, but I estimate that there aren't any real users, so let's trigger a warning in dmesg and return -ENOTTY. See: CVE-2021-4155 Augments: 983d8e60f508 ("xfs: map unwritten blocks in XFS_IOC_{ALLOC,FREE}SP just like fallocate") Signed-off-by: Darrick J. Wong Reviewed-by: Eric Sandeen Reviewed-by: Dave Chinner --- fs/xfs/xfs_bmap_util.c | 7 ++-- fs/xfs/xfs_bmap_util.h | 2 +- fs/xfs/xfs_file.c | 3 +- fs/xfs/xfs_ioctl.c | 92 +++----------------------------------------------- fs/xfs/xfs_ioctl.h | 6 ---- fs/xfs/xfs_ioctl32.c | 27 --------------- 6 files changed, 10 insertions(+), 127 deletions(-) (limited to 'fs') diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 73a36b7be3bd..575060a7c768 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -771,8 +771,7 @@ int xfs_alloc_file_space( struct xfs_inode *ip, xfs_off_t offset, - xfs_off_t len, - int alloc_type) + xfs_off_t len) { xfs_mount_t *mp = ip->i_mount; xfs_off_t count; @@ -865,8 +864,8 @@ xfs_alloc_file_space( goto error; error = xfs_bmapi_write(tp, ip, startoffset_fsb, - allocatesize_fsb, alloc_type, 0, imapp, - &nimaps); + allocatesize_fsb, XFS_BMAPI_PREALLOC, 0, imapp, + &nimaps); if (error) goto error; diff --git a/fs/xfs/xfs_bmap_util.h b/fs/xfs/xfs_bmap_util.h index 9f993168b55b..24b37d211f1d 100644 --- a/fs/xfs/xfs_bmap_util.h +++ b/fs/xfs/xfs_bmap_util.h @@ -54,7 +54,7 @@ int xfs_bmap_last_extent(struct xfs_trans *tp, struct xfs_inode *ip, /* preallocation and hole punch interface */ int xfs_alloc_file_space(struct xfs_inode *ip, xfs_off_t offset, - xfs_off_t len, int alloc_type); + xfs_off_t len); int xfs_free_file_space(struct xfs_inode *ip, xfs_off_t offset, xfs_off_t len); int xfs_collapse_file_space(struct xfs_inode *, xfs_off_t offset, diff --git a/fs/xfs/xfs_file.c b/fs/xfs/xfs_file.c index 27594738b0d1..d81a28cada35 100644 --- a/fs/xfs/xfs_file.c +++ b/fs/xfs/xfs_file.c @@ -1052,8 +1052,7 @@ xfs_file_fallocate( } if (!xfs_is_always_cow_inode(ip)) { - error = xfs_alloc_file_space(ip, offset, len, - XFS_BMAPI_PREALLOC); + error = xfs_alloc_file_space(ip, offset, len); if (error) goto out_unlock; } diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index 29231a8c8a45..64a7ef4a7298 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -627,86 +627,6 @@ xfs_attrmulti_by_handle( return error; } -int -xfs_ioc_space( - struct file *filp, - xfs_flock64_t *bf) -{ - struct inode *inode = file_inode(filp); - struct xfs_inode *ip = XFS_I(inode); - struct iattr iattr; - enum xfs_prealloc_flags flags = XFS_PREALLOC_CLEAR; - uint iolock = XFS_IOLOCK_EXCL | XFS_MMAPLOCK_EXCL; - int error; - - if (inode->i_flags & (S_IMMUTABLE|S_APPEND)) - return -EPERM; - - if (!(filp->f_mode & FMODE_WRITE)) - return -EBADF; - - if (!S_ISREG(inode->i_mode)) - return -EINVAL; - - if (xfs_is_always_cow_inode(ip)) - return -EOPNOTSUPP; - - if (filp->f_flags & O_DSYNC) - flags |= XFS_PREALLOC_SYNC; - if (filp->f_mode & FMODE_NOCMTIME) - flags |= XFS_PREALLOC_INVISIBLE; - - error = mnt_want_write_file(filp); - if (error) - return error; - - xfs_ilock(ip, iolock); - error = xfs_break_layouts(inode, &iolock, BREAK_UNMAP); - if (error) - goto out_unlock; - inode_dio_wait(inode); - - switch (bf->l_whence) { - case 0: /*SEEK_SET*/ - break; - case 1: /*SEEK_CUR*/ - bf->l_start += filp->f_pos; - break; - case 2: /*SEEK_END*/ - bf->l_start += XFS_ISIZE(ip); - break; - default: - error = -EINVAL; - goto out_unlock; - } - - if (bf->l_start < 0 || bf->l_start > inode->i_sb->s_maxbytes) { - error = -EINVAL; - goto out_unlock; - } - - if (bf->l_start > XFS_ISIZE(ip)) { - error = xfs_alloc_file_space(ip, XFS_ISIZE(ip), - bf->l_start - XFS_ISIZE(ip), 0); - if (error) - goto out_unlock; - } - - iattr.ia_valid = ATTR_SIZE; - iattr.ia_size = bf->l_start; - error = xfs_vn_setattr_size(file_mnt_user_ns(filp), file_dentry(filp), - &iattr); - if (error) - goto out_unlock; - - error = xfs_update_prealloc_flags(ip, flags); - -out_unlock: - xfs_iunlock(ip, iolock); - mnt_drop_write_file(filp); - return error; -} - /* Return 0 on success or positive error */ int xfs_fsbulkstat_one_fmt( @@ -1964,13 +1884,11 @@ xfs_file_ioctl( case XFS_IOC_ALLOCSP: case XFS_IOC_FREESP: case XFS_IOC_ALLOCSP64: - case XFS_IOC_FREESP64: { - xfs_flock64_t bf; - - if (copy_from_user(&bf, arg, sizeof(bf))) - return -EFAULT; - return xfs_ioc_space(filp, &bf); - } + case XFS_IOC_FREESP64: + xfs_warn_once(mp, + "%s should use fallocate; XFS_IOC_{ALLOC,FREE}SP ioctl unsupported", + current->comm); + return -ENOTTY; case XFS_IOC_DIOINFO: { struct xfs_buftarg *target = xfs_inode_buftarg(ip); struct dioattr da; diff --git a/fs/xfs/xfs_ioctl.h b/fs/xfs/xfs_ioctl.h index 845d3bcab74b..d4abba2c13c1 100644 --- a/fs/xfs/xfs_ioctl.h +++ b/fs/xfs/xfs_ioctl.h @@ -10,12 +10,6 @@ struct xfs_bstat; struct xfs_ibulk; struct xfs_inogrp; - -extern int -xfs_ioc_space( - struct file *filp, - xfs_flock64_t *bf); - int xfs_ioc_swapext( xfs_swapext_t *sxp); diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c index 8783af203cfc..004ed2a251e8 100644 --- a/fs/xfs/xfs_ioctl32.c +++ b/fs/xfs/xfs_ioctl32.c @@ -27,22 +27,6 @@ _IOC(_IOC_DIR(cmd), _IOC_TYPE(cmd), _IOC_NR(cmd), sizeof(type)) #ifdef BROKEN_X86_ALIGNMENT -STATIC int -xfs_compat_flock64_copyin( - xfs_flock64_t *bf, - compat_xfs_flock64_t __user *arg32) -{ - if (get_user(bf->l_type, &arg32->l_type) || - get_user(bf->l_whence, &arg32->l_whence) || - get_user(bf->l_start, &arg32->l_start) || - get_user(bf->l_len, &arg32->l_len) || - get_user(bf->l_sysid, &arg32->l_sysid) || - get_user(bf->l_pid, &arg32->l_pid) || - copy_from_user(bf->l_pad, &arg32->l_pad, 4*sizeof(u32))) - return -EFAULT; - return 0; -} - STATIC int xfs_compat_ioc_fsgeometry_v1( struct xfs_mount *mp, @@ -445,17 +429,6 @@ xfs_file_compat_ioctl( switch (cmd) { #if defined(BROKEN_X86_ALIGNMENT) - case XFS_IOC_ALLOCSP_32: - case XFS_IOC_FREESP_32: - case XFS_IOC_ALLOCSP64_32: - case XFS_IOC_FREESP64_32: { - struct xfs_flock64 bf; - - if (xfs_compat_flock64_copyin(&bf, arg)) - return -EFAULT; - cmd = _NATIVE_IOC(cmd, struct xfs_flock64); - return xfs_ioc_space(filp, &bf); - } case XFS_IOC_FSGEOMETRY_V1_32: return xfs_compat_ioc_fsgeometry_v1(ip->i_mount, arg); case XFS_IOC_FSGROWFSDATA_32: { -- cgit v1.2.3