mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-11-04 02:30:34 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

btrfs: Fix 32/64-bit problem with BTRFS_SET_RECEIVED_SUBVOL ioctl

Browse source 
The structure for BTRFS_SET_RECEIVED_IOCTL packs differently on 32-bit
and 64-bit systems. This means that it is impossible to use btrfs
receive on a system with a 64-bit kernel and 32-bit userspace, because
the structure size (and hence the ioctl number) is different.

This patch adds a compatibility structure and ioctl to deal with the
above case.

Signed-off-by: Hugo Mills <hugo@carfax.org.uk>
Signed-off-by: Josef Bacik <jbacik@fb.com>
This commit is contained in:
Hugo Mills 2014-01-30 20:17:00 +00:00 committed by Josef Bacik
parent d86477b303
commit abccd00f8a
1 changed files with 111 additions and 12 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

123
fs/btrfs/ioctl.c
View file

@ -59,6 +59,32 @@
#include "props.h"
#include "sysfs.h"
#ifdef CONFIG_64BIT
/* If we have a 32-bit userspace and 64-bit kernel, then the UAPI
* structures are incorrect, as the timespec structure from userspace
* is 4 bytes too small. We define these alternatives here to teach
* the kernel about the 32-bit struct packing.
*/
struct btrfs_ioctl_timespec_32 {
__u64 sec;
__u32 nsec;
} __attribute__ ((__packed__));
struct btrfs_ioctl_received_subvol_args_32 {
char uuid[BTRFS_UUID_SIZE]; /* in */
__u64 stransid; /* in */
__u64 rtransid; /* out */
struct btrfs_ioctl_timespec_32 stime; /* in */
struct btrfs_ioctl_timespec_32 rtime; /* out */
__u64 flags; /* in */
__u64 reserved[16]; /* in */
} __attribute__ ((__packed__));
#define BTRFS_IOC_SET_RECEIVED_SUBVOL_32 _IOWR(BTRFS_IOCTL_MAGIC, 37, \
struct btrfs_ioctl_received_subvol_args_32)
#endif
static int btrfs_clone(struct inode *src, struct inode *inode,
u64 off, u64 olen, u64 olen_aligned, u64 destoff);
@ -4375,10 +4401,9 @@ static long btrfs_ioctl_quota_rescan_wait(struct file *file, void __user *arg)
return btrfs_qgroup_wait_for_completion(root->fs_info);
}
static long btrfs_ioctl_set_received_subvol(struct file *file,
void __user *arg)
static long _btrfs_ioctl_set_received_subvol(struct file *file,
struct btrfs_ioctl_received_subvol_args *sa)
{
struct btrfs_ioctl_received_subvol_args *sa = NULL;
struct inode *inode = file_inode(file);
struct btrfs_root *root = BTRFS_I(inode)->root;
struct btrfs_root_item *root_item = &root->root_item;
@ -4406,13 +4431,6 @@ static long btrfs_ioctl_set_received_subvol(struct file *file,
goto out;
}
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa)) {
ret = PTR_ERR(sa);
sa = NULL;
goto out;
}
/*
* 1 - root item
* 2 - uuid items (received uuid + subvol uuid)
@ -4466,14 +4484,91 @@ static long btrfs_ioctl_set_received_subvol(struct file *file,
goto out;
}
out:
up_write(&root->fs_info->subvol_sem);
mnt_drop_write_file(file);
return ret;
}
#ifdef CONFIG_64BIT
static long btrfs_ioctl_set_received_subvol_32(struct file *file,
void __user *arg)
{
struct btrfs_ioctl_received_subvol_args_32 *args32 = NULL;
struct btrfs_ioctl_received_subvol_args *args64 = NULL;
int ret = 0;
args32 = memdup_user(arg, sizeof(*args32));
if (IS_ERR(args32)) {
ret = PTR_ERR(args32);
args32 = NULL;
goto out;
}
args64 = kmalloc(sizeof(*args64), GFP_NOFS);
if (IS_ERR(args64)) {
ret = PTR_ERR(args64);
args64 = NULL;
goto out;
}
memcpy(args64->uuid, args32->uuid, BTRFS_UUID_SIZE);
args64->stransid = args32->stransid;
args64->rtransid = args32->rtransid;
args64->stime.sec = args32->stime.sec;
args64->stime.nsec = args32->stime.nsec;
args64->rtime.sec = args32->rtime.sec;
args64->rtime.nsec = args32->rtime.nsec;
args64->flags = args32->flags;
ret = _btrfs_ioctl_set_received_subvol(file, args64);
if (ret)
goto out;
memcpy(args32->uuid, args64->uuid, BTRFS_UUID_SIZE);
args32->stransid = args64->stransid;
args32->rtransid = args64->rtransid;
args32->stime.sec = args64->stime.sec;
args32->stime.nsec = args64->stime.nsec;
args32->rtime.sec = args64->rtime.sec;
args32->rtime.nsec = args64->rtime.nsec;
args32->flags = args64->flags;
ret = copy_to_user(arg, args32, sizeof(*args32));
if (ret)
ret = -EFAULT;
out:
kfree(args32);
kfree(args64);
return ret;
}
#endif
static long btrfs_ioctl_set_received_subvol(struct file *file,
void __user *arg)
{
struct btrfs_ioctl_received_subvol_args *sa = NULL;
int ret = 0;
sa = memdup_user(arg, sizeof(*sa));
if (IS_ERR(sa)) {
ret = PTR_ERR(sa);
sa = NULL;
goto out;
}
ret = _btrfs_ioctl_set_received_subvol(file, sa);
if (ret)
goto out;
ret = copy_to_user(arg, sa, sizeof(*sa));
if (ret)
ret = -EFAULT;
out:
kfree(sa);
up_write(&root->fs_info->subvol_sem);
mnt_drop_write_file(file);
return ret;
}
@ -4792,6 +4887,10 @@ long btrfs_ioctl(struct file *file, unsigned int
return btrfs_ioctl_balance_progress(root, argp);
case BTRFS_IOC_SET_RECEIVED_SUBVOL:
return btrfs_ioctl_set_received_subvol(file, argp);
#ifdef CONFIG_64BIT
case BTRFS_IOC_SET_RECEIVED_SUBVOL_32:
return btrfs_ioctl_set_received_subvol_32(file, argp);
#endif
case BTRFS_IOC_SEND:
return btrfs_ioctl_send(file, argp);
case BTRFS_IOC_GET_DEV_STATS: