[PATCH v4 2/2] f2fs: fix compat F2FS_IOC_{MOVE,GARBAGE_COLLECT}_RANGE
From: Chao Yu
Date: Fri Nov 06 2020 - 01:54:11 EST
Eric reported a ioctl bug in below link:
https://lore.kernel.org/linux-f2fs-devel/20201103032234.GB2875@sol.localdomain/
That said, on some 32-bit architectures, u64 has only 32-bit alignment,
notably i386 and x86_32, so that size of struct f2fs_gc_range compiled
in x86_32 is 20 bytes, however the size in x86_64 is 24 bytes, binary
compiled in x86_32 can not call F2FS_IOC_GARBAGE_COLLECT_RANGE successfully
due to mismatched value of ioctl command in between binary and f2fs
module, similarly, F2FS_IOC_MOVE_RANGE will fail too.
In this patch we introduce two ioctls for compatibility of above special
32-bit binary:
- F2FS_IOC32_GARBAGE_COLLECT_RANGE
- F2FS_IOC32_MOVE_RANGE
Reported-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
v4:
- add Reported-by tag
- avoid redundant codes for cleanup
- move compat definitions to .c
fs/f2fs/file.c | 127 +++++++++++++++++++++++++++++++++++++++----------
1 file changed, 101 insertions(+), 26 deletions(-)
diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 22ae8ae0072f..1464a8d8e969 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -2480,26 +2480,19 @@ static int f2fs_ioc_gc(struct file *filp, unsigned long arg)
return ret;
}
-static int f2fs_ioc_gc_range(struct file *filp, unsigned long arg)
+static int __f2fs_ioc_gc_range(struct file *filp, struct f2fs_gc_range *range)
{
- struct inode *inode = file_inode(filp);
- struct f2fs_sb_info *sbi = F2FS_I_SB(inode);
- struct f2fs_gc_range range;
+ struct f2fs_sb_info *sbi = F2FS_I_SB(file_inode(filp));
u64 end;
int ret;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
-
- if (copy_from_user(&range, (struct f2fs_gc_range __user *)arg,
- sizeof(range)))
- return -EFAULT;
-
if (f2fs_readonly(sbi->sb))
return -EROFS;
- end = range.start + range.len;
- if (end < range.start || range.start < MAIN_BLKADDR(sbi) ||
+ end = range->start + range->len;
+ if (end < range->start || range->start < MAIN_BLKADDR(sbi) ||
end >= MAX_BLKADDR(sbi))
return -EINVAL;
@@ -2508,7 +2501,7 @@ static int f2fs_ioc_gc_range(struct file *filp, unsigned long arg)
return ret;
do_more:
- if (!range.sync) {
+ if (!range->sync) {
if (!down_write_trylock(&sbi->gc_lock)) {
ret = -EBUSY;
goto out;
@@ -2517,20 +2510,30 @@ static int f2fs_ioc_gc_range(struct file *filp, unsigned long arg)
down_write(&sbi->gc_lock);
}
- ret = f2fs_gc(sbi, range.sync, true, GET_SEGNO(sbi, range.start));
+ ret = f2fs_gc(sbi, range->sync, true, GET_SEGNO(sbi, range->start));
if (ret) {
if (ret == -EBUSY)
ret = -EAGAIN;
goto out;
}
- range.start += BLKS_PER_SEC(sbi);
- if (range.start <= end)
+ range->start += BLKS_PER_SEC(sbi);
+ if (range->start <= end)
goto do_more;
out:
mnt_drop_write_file(filp);
return ret;
}
+static int f2fs_ioc_gc_range(struct file *filp, unsigned long arg)
+{
+ struct f2fs_gc_range range;
+
+ if (copy_from_user(&range, (struct f2fs_gc_range __user *)arg,
+ sizeof(range)))
+ return -EFAULT;
+ return __f2fs_ioc_gc_range(filp, &range);
+}
+
static int f2fs_ioc_write_checkpoint(struct file *filp, unsigned long arg)
{
struct inode *inode = file_inode(filp);
@@ -2867,9 +2870,9 @@ static int f2fs_move_file_range(struct file *file_in, loff_t pos_in,
return ret;
}
-static int f2fs_ioc_move_range(struct file *filp, unsigned long arg)
+static int __f2fs_ioc_move_range(struct file *filp,
+ struct f2fs_move_range *range)
{
- struct f2fs_move_range range;
struct fd dst;
int err;
@@ -2877,11 +2880,7 @@ static int f2fs_ioc_move_range(struct file *filp, unsigned long arg)
!(filp->f_mode & FMODE_WRITE))
return -EBADF;
- if (copy_from_user(&range, (struct f2fs_move_range __user *)arg,
- sizeof(range)))
- return -EFAULT;
-
- dst = fdget(range.dst_fd);
+ dst = fdget(range->dst_fd);
if (!dst.file)
return -EBADF;
@@ -2894,8 +2893,8 @@ static int f2fs_ioc_move_range(struct file *filp, unsigned long arg)
if (err)
goto err_out;
- err = f2fs_move_file_range(filp, range.pos_in, dst.file,
- range.pos_out, range.len);
+ err = f2fs_move_file_range(filp, range->pos_in, dst.file,
+ range->pos_out, range->len);
mnt_drop_write_file(filp);
err_out:
@@ -2903,6 +2902,16 @@ static int f2fs_ioc_move_range(struct file *filp, unsigned long arg)
return err;
}
+static int f2fs_ioc_move_range(struct file *filp, unsigned long arg)
+{
+ struct f2fs_move_range range;
+
+ if (copy_from_user(&range, (struct f2fs_move_range __user *)arg,
+ sizeof(range)))
+ return -EFAULT;
+ return __f2fs_ioc_move_range(filp, &range);
+}
+
static int f2fs_ioc_flush_device(struct file *filp, unsigned long arg)
{
struct inode *inode = file_inode(filp);
@@ -4230,6 +4239,70 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
}
#ifdef CONFIG_COMPAT
+#if defined(__KERNEL__)
+struct compat_f2fs_gc_range {
+ u32 sync;
+ compat_u64 start;
+ compat_u64 len;
+};
+#define F2FS_IOC32_GARBAGE_COLLECT_RANGE _IOW(F2FS_IOCTL_MAGIC, 11,\
+ struct compat_f2fs_gc_range)
+#endif
+static int f2fs_compat_ioc_gc_range(struct file *file, unsigned long arg)
+{
+ struct f2fs_sb_info *sbi = F2FS_I_SB(file_inode(file));
+ struct compat_f2fs_gc_range __user *urange;
+ struct f2fs_gc_range range;
+ int err;
+
+ if (unlikely(f2fs_cp_error(sbi)))
+ return -EIO;
+ if (!f2fs_is_checkpoint_ready(sbi))
+ return -ENOSPC;
+
+ urange = compat_ptr(arg);
+ err = get_user(range.sync, &urange->sync);
+ err |= get_user(range.start, &urange->start);
+ err |= get_user(range.len, &urange->len);
+ if (err)
+ return -EFAULT;
+
+ return __f2fs_ioc_gc_range(file, &range);
+}
+
+#if defined(__KERNEL__)
+struct compat_f2fs_move_range {
+ u32 dst_fd;
+ compat_u64 pos_in;
+ compat_u64 pos_out;
+ compat_u64 len;
+};
+#define F2FS_IOC32_MOVE_RANGE _IOWR(F2FS_IOCTL_MAGIC, 9, \
+ struct compat_f2fs_move_range)
+#endif
+static int f2fs_compat_ioc_move_range(struct file *file, unsigned long arg)
+{
+ struct f2fs_sb_info *sbi = F2FS_I_SB(file_inode(file));
+ struct compat_f2fs_move_range __user *urange;
+ struct f2fs_move_range range;
+ int err;
+
+ if (unlikely(f2fs_cp_error(sbi)))
+ return -EIO;
+ if (!f2fs_is_checkpoint_ready(sbi))
+ return -ENOSPC;
+
+ urange = compat_ptr(arg);
+ err = get_user(range.dst_fd, &urange->dst_fd);
+ err |= get_user(range.pos_in, &urange->pos_in);
+ err |= get_user(range.pos_out, &urange->pos_out);
+ err |= get_user(range.len, &urange->len);
+ if (err)
+ return -EFAULT;
+
+ return __f2fs_ioc_move_range(file, &range);
+}
+
long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
switch (cmd) {
@@ -4242,6 +4315,10 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case FS_IOC32_GETVERSION:
cmd = FS_IOC_GETVERSION;
break;
+ case F2FS_IOC32_GARBAGE_COLLECT_RANGE:
+ return f2fs_compat_ioc_gc_range(file, arg);
+ case F2FS_IOC32_MOVE_RANGE:
+ return f2fs_compat_ioc_move_range(file, arg);
case F2FS_IOC_START_ATOMIC_WRITE:
case F2FS_IOC_COMMIT_ATOMIC_WRITE:
case F2FS_IOC_START_VOLATILE_WRITE:
@@ -4259,10 +4336,8 @@ long f2fs_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
case FS_IOC_GET_ENCRYPTION_KEY_STATUS:
case FS_IOC_GET_ENCRYPTION_NONCE:
case F2FS_IOC_GARBAGE_COLLECT:
- case F2FS_IOC_GARBAGE_COLLECT_RANGE:
case F2FS_IOC_WRITE_CHECKPOINT:
case F2FS_IOC_DEFRAGMENT:
- case F2FS_IOC_MOVE_RANGE:
case F2FS_IOC_FLUSH_DEVICE:
case F2FS_IOC_GET_FEATURES:
case FS_IOC_FSGETXATTR:
--
2.26.2