[PATCH 1/5] vfs: create a generic checking and prep function for FS_IOC_SETFLAGS
From: Darrick J. Wong <hidden>
Date: 2019-06-28 18:35:58
Also in:
linux-btrfs, linux-efi, linux-f2fs-devel, linux-fsdevel, linux-xfs, lkml
Subsystem:
btrfs file system, efi variable filesystem, ext2 file system, ext4 file system, f2fs file system, filesystems (vfs and infrastructure), gfs2 file system, hfsplus filesystem, jfs filesystem, nilfs2 filesystem, oracle cluster filesystem 2 (ocfs2), orangefs filesystem, the rest, ubi file system (ubifs) · Maintainers:
Chris Mason, David Sterba, Jeremy Kerr, Ard Biesheuvel, Jan Kara, "Theodore Ts'o", Jaegeuk Kim, Chao Yu, Alexander Viro, Christian Brauner, Andreas Gruenbacher, Viacheslav Dubeyko, John Paul Adrian Glaubitz, Yangtao Li, Dave Kleikamp, Ryusuke Konishi, Mark Fasheh, Joel Becker, Joseph Qi, Mike Marshall, Linus Torvalds, Richard Weinberger
From: Darrick J. Wong <redacted> Create a generic function to check incoming FS_IOC_SETFLAGS flag values and later prepare the inode for updates so that we can standardize the implementations that follow ext4's flag values. Note that the efivarfs implementation no longer fails a no-op SETFLAGS without CAP_LINUX_IMMUTABLE since that's the behavior in ext*. Signed-off-by: Darrick J. Wong <redacted> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: David Sterba <dsterba@suse.com> Reviewed-by: Bob Peterson <redacted> --- fs/btrfs/ioctl.c | 13 +++++-------- fs/efivarfs/file.c | 26 +++++++++++++++++--------- fs/ext2/ioctl.c | 16 ++++------------ fs/ext4/ioctl.c | 13 +++---------- fs/f2fs/file.c | 7 ++++--- fs/gfs2/file.c | 42 +++++++++++++++++++++++++++++------------- fs/hfsplus/ioctl.c | 21 ++++++++++++--------- fs/inode.c | 24 ++++++++++++++++++++++++ fs/jfs/ioctl.c | 22 +++++++--------------- fs/nilfs2/ioctl.c | 9 ++------- fs/ocfs2/ioctl.c | 13 +++---------- fs/orangefs/file.c | 35 ++++++++++++++++++++++++++--------- fs/reiserfs/ioctl.c | 10 ++++------ fs/ubifs/ioctl.c | 13 +++---------- include/linux/fs.h | 3 +++ 15 files changed, 146 insertions(+), 121 deletions(-)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 6dafa857bbb9..d3d9b4abb09b 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c@@ -187,7 +187,7 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg) struct btrfs_inode *binode = BTRFS_I(inode); struct btrfs_root *root = binode->root; struct btrfs_trans_handle *trans; - unsigned int fsflags; + unsigned int fsflags, old_fsflags; int ret; const char *comp = NULL; u32 binode_flags = binode->flags;
@@ -212,13 +212,10 @@ static int btrfs_ioctl_setflags(struct file *file, void __user *arg) inode_lock(inode); fsflags = btrfs_mask_fsflags_for_type(inode, fsflags); - if ((fsflags ^ btrfs_inode_flags_to_fsflags(binode->flags)) & - (FS_APPEND_FL | FS_IMMUTABLE_FL)) { - if (!capable(CAP_LINUX_IMMUTABLE)) { - ret = -EPERM; - goto out_unlock; - } - } + old_fsflags = btrfs_inode_flags_to_fsflags(binode->flags); + ret = vfs_ioc_setflags_prepare(inode, old_fsflags, fsflags); + if (ret) + goto out_unlock; if (fsflags & FS_SYNC_FL) binode_flags |= BTRFS_INODE_SYNC;
diff --git a/fs/efivarfs/file.c b/fs/efivarfs/file.c
index 8e568428c88b..a3cc10b1bfe1 100644
--- a/fs/efivarfs/file.c
+++ b/fs/efivarfs/file.c@@ -110,16 +110,22 @@ static ssize_t efivarfs_file_read(struct file *file, char __user *userbuf, return size; } -static int -efivarfs_ioc_getxflags(struct file *file, void __user *arg) +static inline unsigned int efivarfs_getflags(struct inode *inode) { - struct inode *inode = file->f_mapping->host; unsigned int i_flags; unsigned int flags = 0; i_flags = inode->i_flags; if (i_flags & S_IMMUTABLE) flags |= FS_IMMUTABLE_FL; + return flags; +} + +static int +efivarfs_ioc_getxflags(struct file *file, void __user *arg) +{ + struct inode *inode = file->f_mapping->host; + unsigned int flags = efivarfs_getflags(inode); if (copy_to_user(arg, &flags, sizeof(flags))) return -EFAULT;
@@ -132,6 +138,7 @@ efivarfs_ioc_setxflags(struct file *file, void __user *arg) struct inode *inode = file->f_mapping->host; unsigned int flags; unsigned int i_flags = 0; + unsigned int oldflags = efivarfs_getflags(inode); int error; if (!inode_owner_or_capable(inode))
@@ -143,9 +150,6 @@ efivarfs_ioc_setxflags(struct file *file, void __user *arg) if (flags & ~FS_IMMUTABLE_FL) return -EOPNOTSUPP; - if (!capable(CAP_LINUX_IMMUTABLE)) - return -EPERM; - if (flags & FS_IMMUTABLE_FL) i_flags |= S_IMMUTABLE;
@@ -155,12 +159,16 @@ efivarfs_ioc_setxflags(struct file *file, void __user *arg) return error; inode_lock(inode); + + error = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (error) + goto out; + inode_set_flags(inode, i_flags, S_IMMUTABLE); +out: inode_unlock(inode); - mnt_drop_write_file(file); - - return 0; + return error; } static long
diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
index 0367c0039e68..1b853fb0b163 100644
--- a/fs/ext2/ioctl.c
+++ b/fs/ext2/ioctl.c@@ -60,18 +60,10 @@ long ext2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) } oldflags = ei->i_flags; - /* - * The IMMUTABLE and APPEND_ONLY flags can only be changed by - * the relevant capability. - * - * This test looks nicer. Thanks to Pauline Middelink - */ - if ((flags ^ oldflags) & (EXT2_APPEND_FL | EXT2_IMMUTABLE_FL)) { - if (!capable(CAP_LINUX_IMMUTABLE)) { - inode_unlock(inode); - ret = -EPERM; - goto setflags_out; - } + ret = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (ret) { + inode_unlock(inode); + goto setflags_out; } flags = flags & EXT2_FL_USER_MODIFIABLE;
diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index e486e49b31ed..272b6e44191b 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c@@ -289,16 +289,9 @@ static int ext4_ioctl_setflags(struct inode *inode, /* The JOURNAL_DATA flag is modifiable only by root */ jflag = flags & EXT4_JOURNAL_DATA_FL; - /* - * The IMMUTABLE and APPEND_ONLY flags can only be changed by - * the relevant capability. - * - * This test looks nicer. Thanks to Pauline Middelink - */ - if ((flags ^ oldflags) & (EXT4_APPEND_FL | EXT4_IMMUTABLE_FL)) { - if (!capable(CAP_LINUX_IMMUTABLE)) - goto flags_out; - } + err = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (err) + goto flags_out; /* * The JOURNAL_DATA flag can only be changed by
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 45b45f37d347..845ae6f43ebc 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c@@ -1670,6 +1670,7 @@ static int __f2fs_ioc_setflags(struct inode *inode, unsigned int flags) { struct f2fs_inode_info *fi = F2FS_I(inode); unsigned int oldflags; + int err; /* Is it quota file? Do not allow user to mess with it */ if (IS_NOQUOTA(inode))
@@ -1679,9 +1680,9 @@ static int __f2fs_ioc_setflags(struct inode *inode, unsigned int flags) oldflags = fi->i_flags; - if ((flags ^ oldflags) & (F2FS_APPEND_FL | F2FS_IMMUTABLE_FL)) - if (!capable(CAP_LINUX_IMMUTABLE)) - return -EPERM; + err = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (err) + return err; flags = flags & F2FS_FL_USER_MODIFIABLE; flags |= oldflags & ~F2FS_FL_USER_MODIFIABLE;
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c
index d174b1f8fd08..1cb0c3afd3dc 100644
--- a/fs/gfs2/file.c
+++ b/fs/gfs2/file.c@@ -136,27 +136,36 @@ static struct { {FS_JOURNAL_DATA_FL, GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA}, }; +static inline u32 gfs2_gfsflags_to_fsflags(struct inode *inode, u32 gfsflags) +{ + int i; + u32 fsflags = 0; + + if (S_ISDIR(inode->i_mode)) + gfsflags &= ~GFS2_DIF_JDATA; + else + gfsflags &= ~GFS2_DIF_INHERIT_JDATA; + + for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++) + if (gfsflags & fsflag_gfs2flag[i].gfsflag) + fsflags |= fsflag_gfs2flag[i].fsflag; + return fsflags; +} + static int gfs2_get_flags(struct file *filp, u32 __user *ptr) { struct inode *inode = file_inode(filp); struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder gh; - int i, error; - u32 gfsflags, fsflags = 0; + int error; + u32 fsflags; gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh); error = gfs2_glock_nq(&gh); if (error) goto out_uninit; - gfsflags = ip->i_diskflags; - if (S_ISDIR(inode->i_mode)) - gfsflags &= ~GFS2_DIF_JDATA; - else - gfsflags &= ~GFS2_DIF_INHERIT_JDATA; - for (i = 0; i < ARRAY_SIZE(fsflag_gfs2flag); i++) - if (gfsflags & fsflag_gfs2flag[i].gfsflag) - fsflags |= fsflag_gfs2flag[i].fsflag; + fsflags = gfs2_gfsflags_to_fsflags(inode, ip->i_diskflags); if (put_user(fsflags, ptr)) error = -EFAULT;
@@ -200,9 +209,11 @@ void gfs2_set_inode_flags(struct inode *inode) * @filp: file pointer * @reqflags: The flags to set * @mask: Indicates which flags are valid + * @fsflags: The FS_* inode flags passed in * */ -static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) +static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask, + const u32 fsflags) { struct inode *inode = file_inode(filp); struct gfs2_inode *ip = GFS2_I(inode);
@@ -210,7 +221,7 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) struct buffer_head *bh; struct gfs2_holder gh; int error; - u32 new_flags, flags; + u32 new_flags, flags, oldflags; error = mnt_want_write_file(filp); if (error)
@@ -220,6 +231,11 @@ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) if (error) goto out_drop_write; + oldflags = gfs2_gfsflags_to_fsflags(inode, ip->i_diskflags); + error = vfs_ioc_setflags_prepare(inode, oldflags, fsflags); + if (error) + goto out; + error = -EACCES; if (!inode_owner_or_capable(inode)) goto out;
@@ -308,7 +324,7 @@ static int gfs2_set_flags(struct file *filp, u32 __user *ptr) mask &= ~(GFS2_DIF_TOPDIR | GFS2_DIF_INHERIT_JDATA); } - return do_gfs2_set_flags(filp, gfsflags, mask); + return do_gfs2_set_flags(filp, gfsflags, mask, fsflags); } static int gfs2_getlabel(struct file *filp, char __user *label)
diff --git a/fs/hfsplus/ioctl.c b/fs/hfsplus/ioctl.c
index 5e6502ef7415..ce15b9496b77 100644
--- a/fs/hfsplus/ioctl.c
+++ b/fs/hfsplus/ioctl.c@@ -57,9 +57,8 @@ static int hfsplus_ioctl_bless(struct file *file, int __user *user_flags) return 0; } -static int hfsplus_ioctl_getflags(struct file *file, int __user *user_flags) +static inline unsigned int hfsplus_getflags(struct inode *inode) { - struct inode *inode = file_inode(file); struct hfsplus_inode_info *hip = HFSPLUS_I(inode); unsigned int flags = 0;
@@ -69,6 +68,13 @@ static int hfsplus_ioctl_getflags(struct file *file, int __user *user_flags) flags |= FS_APPEND_FL; if (hip->userflags & HFSPLUS_FLG_NODUMP) flags |= FS_NODUMP_FL; + return flags; +} + +static int hfsplus_ioctl_getflags(struct file *file, int __user *user_flags) +{ + struct inode *inode = file_inode(file); + unsigned int flags = hfsplus_getflags(inode); return put_user(flags, user_flags); }
@@ -78,6 +84,7 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags) struct inode *inode = file_inode(file); struct hfsplus_inode_info *hip = HFSPLUS_I(inode); unsigned int flags, new_fl = 0; + unsigned int oldflags = hfsplus_getflags(inode); int err = 0; err = mnt_want_write_file(file);
@@ -96,13 +103,9 @@ static int hfsplus_ioctl_setflags(struct file *file, int __user *user_flags) inode_lock(inode); - if ((flags & (FS_IMMUTABLE_FL|FS_APPEND_FL)) || - inode->i_flags & (S_IMMUTABLE|S_APPEND)) { - if (!capable(CAP_LINUX_IMMUTABLE)) { - err = -EPERM; - goto out_unlock_inode; - } - } + err = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (err) + goto out_unlock_inode; /* don't silently ignore unsupported ext2 flags */ if (flags & ~(FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NODUMP_FL)) {
diff --git a/fs/inode.c b/fs/inode.c
index 4348cfb14562..9cd1b6501e97 100644
--- a/fs/inode.c
+++ b/fs/inode.c@@ -2190,3 +2190,27 @@ struct timespec64 current_time(struct inode *inode) return timespec64_trunc(now, inode->i_sb->s_time_gran); } EXPORT_SYMBOL(current_time); + +/* + * Generic function to check FS_IOC_SETFLAGS values and reject any invalid + * configurations. + * + * Note: the caller should be holding i_mutex, or else be sure that they have + * exclusive access to the inode structure. + */ +int vfs_ioc_setflags_prepare(struct inode *inode, unsigned int oldflags, + unsigned int flags) +{ + /* + * The IMMUTABLE and APPEND_ONLY flags can only be changed by + * the relevant capability. + * + * This test looks nicer. Thanks to Pauline Middelink + */ + if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL) && + !capable(CAP_LINUX_IMMUTABLE)) + return -EPERM; + + return 0; +} +EXPORT_SYMBOL(vfs_ioc_setflags_prepare);
diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
index ba34dae8bd9f..10ee0ecca1a8 100644
--- a/fs/jfs/ioctl.c
+++ b/fs/jfs/ioctl.c@@ -98,24 +98,16 @@ long jfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) /* Lock against other parallel changes of flags */ inode_lock(inode); - oldflags = jfs_inode->mode2; - - /* - * The IMMUTABLE and APPEND_ONLY flags can only be changed by - * the relevant capability. - */ - if ((oldflags & JFS_IMMUTABLE_FL) || - ((flags ^ oldflags) & - (JFS_APPEND_FL | JFS_IMMUTABLE_FL))) { - if (!capable(CAP_LINUX_IMMUTABLE)) { - inode_unlock(inode); - err = -EPERM; - goto setflags_out; - } + oldflags = jfs_map_ext2(jfs_inode->mode2 & JFS_FL_USER_VISIBLE, + 0); + err = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (err) { + inode_unlock(inode); + goto setflags_out; } flags = flags & JFS_FL_USER_MODIFIABLE; - flags |= oldflags & ~JFS_FL_USER_MODIFIABLE; + flags |= jfs_inode->mode2 & ~JFS_FL_USER_MODIFIABLE; jfs_inode->mode2 = flags; jfs_set_inode_flags(inode);
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 9b96d79eea6c..91b9dac6b2cc 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c@@ -148,13 +148,8 @@ static int nilfs_ioctl_setflags(struct inode *inode, struct file *filp, oldflags = NILFS_I(inode)->i_flags; - /* - * The IMMUTABLE and APPEND_ONLY flags can only be changed by the - * relevant capability. - */ - ret = -EPERM; - if (((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) && - !capable(CAP_LINUX_IMMUTABLE)) + ret = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (ret) goto out; ret = nilfs_transaction_begin(inode->i_sb, &ti, 0);
diff --git a/fs/ocfs2/ioctl.c b/fs/ocfs2/ioctl.c
index 994726ada857..d6f7b299eb23 100644
--- a/fs/ocfs2/ioctl.c
+++ b/fs/ocfs2/ioctl.c@@ -106,16 +106,9 @@ static int ocfs2_set_inode_attr(struct inode *inode, unsigned flags, flags = flags & mask; flags |= oldflags & ~mask; - /* - * The IMMUTABLE and APPEND_ONLY flags can only be changed by - * the relevant capability. - */ - status = -EPERM; - if ((oldflags & OCFS2_IMMUTABLE_FL) || ((flags ^ oldflags) & - (OCFS2_APPEND_FL | OCFS2_IMMUTABLE_FL))) { - if (!capable(CAP_LINUX_IMMUTABLE)) - goto bail_unlock; - } + status = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (status) + goto bail_unlock; handle = ocfs2_start_trans(osb, OCFS2_INODE_UPDATE_CREDITS); if (IS_ERR(handle)) {
diff --git a/fs/orangefs/file.c b/fs/orangefs/file.c
index a35c17017210..5b1dd00e8eca 100644
--- a/fs/orangefs/file.c
+++ b/fs/orangefs/file.c@@ -357,11 +357,28 @@ static ssize_t orangefs_file_write_iter(struct kiocb *iocb, return ret; } +static int orangefs_getflags(struct inode *inode, unsigned long *uval) +{ + __u64 val = 0; + int ret; + + ret = orangefs_inode_getxattr(inode, + "user.pvfs2.meta_hint", + &val, sizeof(val)); + if (ret < 0 && ret != -ENODATA) + return ret; + else if (ret == -ENODATA) + val = 0; + uval = val; + return 0; +} + /* * Perform a miscellaneous operation on a file. */ static long orangefs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { + struct inode *inode = file_ioctl(file); int ret = -ENOTTY; __u64 val = 0; unsigned long uval;
@@ -375,15 +392,9 @@ static long orangefs_ioctl(struct file *file, unsigned int cmd, unsigned long ar * and append flags */ if (cmd == FS_IOC_GETFLAGS) { - val = 0; - ret = orangefs_inode_getxattr(file_inode(file), - "user.pvfs2.meta_hint", - &val, sizeof(val)); - if (ret < 0 && ret != -ENODATA) + ret = orangefs_getflags(inode, &uval); + if (ret) return ret; - else if (ret == -ENODATA) - val = 0; - uval = val; gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_ioctl: FS_IOC_GETFLAGS: %llu\n", (unsigned long long)uval);
@@ -404,11 +415,17 @@ static long orangefs_ioctl(struct file *file, unsigned int cmd, unsigned long ar gossip_err("orangefs_ioctl: the FS_IOC_SETFLAGS only supports setting one of FS_IMMUTABLE_FL|FS_APPEND_FL|FS_NOATIME_FL\n"); return -EINVAL; } + ret = orangefs_getflags(inode, &old_uval); + if (ret) + return ret; + ret = vfs_ioc_setflags_prepare(inode, old_uval, uval); + if (ret) + return ret; val = uval; gossip_debug(GOSSIP_FILE_DEBUG, "orangefs_ioctl: FS_IOC_SETFLAGS: %llu\n", (unsigned long long)val); - ret = orangefs_inode_setxattr(file_inode(file), + ret = orangefs_inode_setxattr(inode, "user.pvfs2.meta_hint", &val, sizeof(val), 0); }
diff --git a/fs/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c
index acbbaf7a0bb2..45e1a5d11af3 100644
--- a/fs/reiserfs/ioctl.c
+++ b/fs/reiserfs/ioctl.c@@ -74,13 +74,11 @@ long reiserfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) err = -EPERM; goto setflags_out; } - if (((flags ^ REISERFS_I(inode)-> - i_attrs) & (REISERFS_IMMUTABLE_FL | - REISERFS_APPEND_FL)) - && !capable(CAP_LINUX_IMMUTABLE)) { - err = -EPERM; + err = vfs_ioc_setflags_prepare(inode, + REISERFS_I(inode)->i_attrs, + flags); + if (err) goto setflags_out; - } if ((flags & REISERFS_NOTAIL_FL) && S_ISREG(inode->i_mode)) { int result;
diff --git a/fs/ubifs/ioctl.c b/fs/ubifs/ioctl.c
index 4f1a397fda69..034ad14710d1 100644
--- a/fs/ubifs/ioctl.c
+++ b/fs/ubifs/ioctl.c@@ -107,18 +107,11 @@ static int setflags(struct inode *inode, int flags) if (err) return err; - /* - * The IMMUTABLE and APPEND_ONLY flags can only be changed by - * the relevant capability. - */ mutex_lock(&ui->ui_mutex); oldflags = ubifs2ioctl(ui->flags); - if ((flags ^ oldflags) & (FS_APPEND_FL | FS_IMMUTABLE_FL)) { - if (!capable(CAP_LINUX_IMMUTABLE)) { - err = -EPERM; - goto out_unlock; - } - } + err = vfs_ioc_setflags_prepare(inode, oldflags, flags); + if (err) + goto out_unlock; ui->flags = ioctl2ubifs(flags); ubifs_set_inode_flags(inode);
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 79ffa2958bd8..3f74066d3f44 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h@@ -3555,4 +3555,7 @@ static inline struct sock *io_uring_get_socket(struct file *file) } #endif +int vfs_ioc_setflags_prepare(struct inode *inode, unsigned int oldflags, + unsigned int flags); + #endif /* _LINUX_FS_H */