Replace fiemap_check_flags with a fiemap_validate helpers that also takes the inode and mapped range, and performs the sanity check and truncation previously done in fiemap_check_range. This way the validation is inside the file system itself and thus properly works for the stacked overlayfs case as well. Signed-off-by: Christoph Hellwig <hch@xxxxxx> --- Documentation/filesystems/fiemap.txt | 8 ++--- fs/btrfs/inode.c | 2 +- fs/cifs/smb2ops.c | 3 +- fs/ext4/extents.c | 5 +-- fs/f2fs/data.c | 3 +- fs/ioctl.c | 51 +++++++++++----------------- fs/iomap/fiemap.c | 2 +- fs/nilfs2/inode.c | 2 +- fs/ocfs2/extent_map.c | 3 +- include/linux/fiemap.h | 3 +- 10 files changed, 37 insertions(+), 45 deletions(-) diff --git a/Documentation/filesystems/fiemap.txt b/Documentation/filesystems/fiemap.txt index ac87e6fda842b..cf757a9191ef2 100644 --- a/Documentation/filesystems/fiemap.txt +++ b/Documentation/filesystems/fiemap.txt @@ -203,15 +203,13 @@ EINTR once fatal signal received. Flag checking should be done at the beginning of the ->fiemap callback via the -fiemap_check_flags() helper: - -int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); +fiemap_validate() helper. The struct fieinfo should be passed in as received from ioctl_fiemap(). The set of fiemap flags which the fs understands should be passed via fs_flags. If -fiemap_check_flags finds invalid user flags, it will place the bad values in +fiemap_validate finds invalid user flags, it will place the bad values in fieinfo->fi_flags and return -EBADR. If the file system gets -EBADR, from -fiemap_check_flags(), it should immediately exit, returning that error back to +fiemap_validate(), it should immediately exit, returning that error back to ioctl_fiemap(). diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 320d1062068d3..8382b9edcbb09 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8250,7 +8250,7 @@ static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, { int ret; - ret = fiemap_check_flags(fieinfo, BTRFS_FIEMAP_FLAGS); + ret = fiemap_validate(inode, fieinfo, start, &len, BTRFS_FIEMAP_FLAGS); if (ret) return ret; diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c index 09047f1ddfb66..bf00329e720e4 100644 --- a/fs/cifs/smb2ops.c +++ b/fs/cifs/smb2ops.c @@ -3408,7 +3408,8 @@ static int smb3_fiemap(struct cifs_tcon *tcon, int i, num, rc, flags, last_blob; u64 next; - if (fiemap_check_flags(fei, FIEMAP_FLAG_SYNC)) + if (fiemap_validate(cfile->dentry->d_inode, fei, start, &len, + FIEMAP_FLAG_SYNC)) return -EBADR; xid = get_xid(); diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index a41ae7c510170..4541ff2ecc469 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -4908,8 +4908,9 @@ int ext4_get_es_cache(struct inode *inode, struct fiemap_extent_info *fieinfo, fieinfo->fi_flags &= ~FIEMAP_FLAG_CACHE; } - if (fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC)) - return -EBADR; + error = fiemap_validate(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC); + if (error) + return error; error = ext4_fiemap_check_ranges(inode, start, &len); if (error) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 25abbbb65ba09..a33e03ecd5e89 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1825,7 +1825,8 @@ int f2fs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, return ret; } - ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR); + ret = fiemap_validate(inode, fieinfo, start, &len, + FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR); if (ret) return ret; diff --git a/fs/ioctl.c b/fs/ioctl.c index cbc84e23d00bd..11e95fa010ae8 100644 --- a/fs/ioctl.c +++ b/fs/ioctl.c @@ -141,8 +141,11 @@ int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical, EXPORT_SYMBOL(fiemap_fill_next_extent); /** - * fiemap_check_flags - check validity of requested flags for fiemap + * fiemap_validate - check validity of requested flags for fiemap + * @inode: Inode to operate on * @fieinfo: Fiemap context passed into ->fiemap + * @start: Start of the mapped range + * @len: Length of the mapped range, can be truncated by this function. * @fs_flags: Set of fiemap flags that the file system understands * * Called from file system ->fiemap callback. This will compute the @@ -154,48 +157,38 @@ EXPORT_SYMBOL(fiemap_fill_next_extent); * * Returns 0 on success, -EBADR on bad flags. */ -int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags) +int fiemap_validate(struct inode *inode, struct fiemap_extent_info *fieinfo, + u64 start, u64 *len, u32 fs_flags) { + u64 maxbytes = inode->i_sb->s_maxbytes; u32 incompat_flags; - incompat_flags = fieinfo->fi_flags & ~(FIEMAP_FLAGS_COMPAT & fs_flags); - if (incompat_flags) { - fieinfo->fi_flags = incompat_flags; - return -EBADR; - } - return 0; -} -EXPORT_SYMBOL(fiemap_check_flags); - -static int fiemap_check_ranges(struct super_block *sb, - u64 start, u64 len, u64 *new_len) -{ - u64 maxbytes = (u64) sb->s_maxbytes; - - *new_len = len; - - if (len == 0) + if (*len == 0) return -EINVAL; - if (start > maxbytes) return -EFBIG; /* * Shrink request scope to what the fs can actually handle. */ - if (len > maxbytes || (maxbytes - len) < start) - *new_len = maxbytes - start; + if (*len > maxbytes || (maxbytes - *len) < start) + *len = maxbytes - start; + + incompat_flags = fieinfo->fi_flags & ~(FIEMAP_FLAGS_COMPAT & fs_flags); + if (incompat_flags) { + fieinfo->fi_flags = incompat_flags; + return -EBADR; + } return 0; } +EXPORT_SYMBOL(fiemap_validate); static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap) { struct fiemap fiemap; struct fiemap_extent_info fieinfo = { 0, }; struct inode *inode = file_inode(filp); - struct super_block *sb = inode->i_sb; - u64 len; int error; if (!inode->i_op->fiemap) @@ -207,11 +200,6 @@ static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap) if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS) return -EINVAL; - error = fiemap_check_ranges(sb, fiemap.fm_start, fiemap.fm_length, - &len); - if (error) - return error; - fieinfo.fi_flags = fiemap.fm_flags; fieinfo.fi_extents_max = fiemap.fm_extent_count; fieinfo.fi_extents_start = ufiemap->fm_extents; @@ -224,7 +212,8 @@ static int ioctl_fiemap(struct file *filp, struct fiemap __user *ufiemap) if (fieinfo.fi_flags & FIEMAP_FLAG_SYNC) filemap_write_and_wait(inode->i_mapping); - error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start, len); + error = inode->i_op->fiemap(inode, &fieinfo, fiemap.fm_start, + fiemap.fm_length); fiemap.fm_flags = fieinfo.fi_flags; fiemap.fm_mapped_extents = fieinfo.fi_extents_mapped; if (copy_to_user(ufiemap, &fiemap, sizeof(fiemap))) @@ -312,7 +301,7 @@ static int __generic_block_fiemap(struct inode *inode, bool past_eof = false, whole_file = false; int ret = 0; - ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC); + ret = fiemap_validate(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC); if (ret) return ret; diff --git a/fs/iomap/fiemap.c b/fs/iomap/fiemap.c index dd04e4added15..eb21a483ee776 100644 --- a/fs/iomap/fiemap.c +++ b/fs/iomap/fiemap.c @@ -75,7 +75,7 @@ int iomap_fiemap(struct inode *inode, struct fiemap_extent_info *fi, ctx.fi = fi; ctx.prev.type = IOMAP_HOLE; - ret = fiemap_check_flags(fi, FIEMAP_FLAG_SYNC); + ret = fiemap_validate(inode, fi, start, &len, FIEMAP_FLAG_SYNC); if (ret) return ret; diff --git a/fs/nilfs2/inode.c b/fs/nilfs2/inode.c index 6e1aca38931f3..93402e7fd2104 100644 --- a/fs/nilfs2/inode.c +++ b/fs/nilfs2/inode.c @@ -1006,7 +1006,7 @@ int nilfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, unsigned int blkbits = inode->i_blkbits; int ret, n; - ret = fiemap_check_flags(fieinfo, FIEMAP_FLAG_SYNC); + ret = fiemap_validate(inode, fieinfo, start, &len, FIEMAP_FLAG_SYNC); if (ret) return ret; diff --git a/fs/ocfs2/extent_map.c b/fs/ocfs2/extent_map.c index e3e2d1b2af51a..5b6c2b52a68bd 100644 --- a/fs/ocfs2/extent_map.c +++ b/fs/ocfs2/extent_map.c @@ -746,7 +746,8 @@ int ocfs2_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, struct buffer_head *di_bh = NULL; struct ocfs2_extent_rec rec; - ret = fiemap_check_flags(fieinfo, OCFS2_FIEMAP_FLAGS); + ret = fiemap_validate(inode, fieinfo, map_start, &map_len, + OCFS2_FIEMAP_FLAGS); if (ret) return ret; diff --git a/include/linux/fiemap.h b/include/linux/fiemap.h index 240d4f7d9116a..a5b328bbb69b6 100644 --- a/include/linux/fiemap.h +++ b/include/linux/fiemap.h @@ -13,9 +13,10 @@ struct fiemap_extent_info { fiemap_extent array */ }; +int fiemap_validate(struct inode *inode, struct fiemap_extent_info *fieinfo, + u64 start, u64 *len, u32 fs_flags); int fiemap_fill_next_extent(struct fiemap_extent_info *info, u64 logical, u64 phys, u64 len, u32 flags); -int fiemap_check_flags(struct fiemap_extent_info *fieinfo, u32 fs_flags); int generic_block_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo, u64 start, u64 len, -- 2.26.1