[PATCH v2 1/4] vfs: create a generic checking function for FS_IOC_SETFLAGS
From: Darrick J. Wong
Date: Tue Jun 11 2019 - 20:48:42 EST
From: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
Create a generic checking function for the incoming FS_IOC_SETFLAGS flag
values so that we can standardize the implementations that follow ext4's
flag values.
Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx>
---
v2: fix jfs locking and remove its opencoded flags check
---
fs/btrfs/ioctl.c | 13 +++++--------
fs/efivarfs/file.c | 18 +++++++++++++-----
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 | 17 +++++++++++++++++
fs/jfs/ioctl.c | 22 +++++++---------------
fs/nilfs2/ioctl.c | 9 ++-------
fs/ocfs2/ioctl.c | 13 +++----------
fs/reiserfs/ioctl.c | 10 ++++------
fs/ubifs/ioctl.c | 13 +++----------
include/linux/fs.h | 2 ++
14 files changed, 108 insertions(+), 108 deletions(-)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 6dafa857bbb9..f408aa93b0cf 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_check(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..f4f6c1bec132 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))
@@ -143,8 +150,9 @@ efivarfs_ioc_setxflags(struct file *file, void __user *arg)
if (flags & ~FS_IMMUTABLE_FL)
return -EOPNOTSUPP;
- if (!capable(CAP_LINUX_IMMUTABLE))
- return -EPERM;
+ error = vfs_ioc_setflags_check(inode, oldflags, flags);
+ if (error)
+ return error;
if (flags & FS_IMMUTABLE_FL)
i_flags |= S_IMMUTABLE;
diff --git a/fs/ext2/ioctl.c b/fs/ext2/ioctl.c
index 0367c0039e68..88b3b9720023 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_check(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..5126ee351a84 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_check(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..a969d5497e03 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_check(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..99f53cf699c6 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_check(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..862a3c9481d7 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_check(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 df6542ec3b88..0ce60b720608 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -2170,3 +2170,20 @@ 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. */
+int vfs_ioc_setflags_check(struct inode *inode, int oldflags, 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_check);
diff --git a/fs/jfs/ioctl.c b/fs/jfs/ioctl.c
index ba34dae8bd9f..b485c2d7620f 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_check(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..0632336d2515 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_check(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..467a2faf0305 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_check(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/reiserfs/ioctl.c b/fs/reiserfs/ioctl.c
index acbbaf7a0bb2..92bcb1ecd994 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_check(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..bdea836fc38b 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_check(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 f7fdfe93e25d..1825d055808c 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3546,4 +3546,6 @@ static inline struct sock *io_uring_get_socket(struct file *file)
}
#endif
+int vfs_ioc_setflags_check(struct inode *inode, int oldflags, int flags);
+
#endif /* _LINUX_FS_H */