Revision 7561cea5dbb97fecb952548a0fb74fb105bf4664 authored by Darrick J. Wong on 01 July 2022, 16:08:33 UTC, committed by Darrick J. Wong on 01 July 2022, 16:09:52 UTC
KASAN reported the following use after free bug when running generic/475: XFS (dm-0): Mounting V5 Filesystem XFS (dm-0): Starting recovery (logdev: internal) XFS (dm-0): Ending recovery (logdev: internal) Buffer I/O error on dev dm-0, logical block 20639616, async page read Buffer I/O error on dev dm-0, logical block 20639617, async page read XFS (dm-0): log I/O error -5 XFS (dm-0): Filesystem has been shut down due to log error (0x2). XFS (dm-0): Unmounting Filesystem XFS (dm-0): Please unmount the filesystem and rectify the problem(s). ================================================================== BUG: KASAN: use-after-free in do_raw_spin_lock+0x246/0x270 Read of size 4 at addr ffff888109dd84c4 by task 3:1H/136 CPU: 3 PID: 136 Comm: 3:1H Not tainted 5.19.0-rc4-xfsx #rc4 8e53ab5ad0fddeb31cee5e7063ff9c361915a9c4 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.15.0-1 04/01/2014 Workqueue: xfs-log/dm-0 xlog_ioend_work [xfs] Call Trace: <TASK> dump_stack_lvl+0x34/0x44 print_report.cold+0x2b8/0x661 ? do_raw_spin_lock+0x246/0x270 kasan_report+0xab/0x120 ? do_raw_spin_lock+0x246/0x270 do_raw_spin_lock+0x246/0x270 ? rwlock_bug.part.0+0x90/0x90 xlog_force_shutdown+0xf6/0x370 [xfs 4ad76ae0d6add7e8183a553e624c31e9ed567318] xlog_ioend_work+0x100/0x190 [xfs 4ad76ae0d6add7e8183a553e624c31e9ed567318] process_one_work+0x672/0x1040 worker_thread+0x59b/0xec0 ? __kthread_parkme+0xc6/0x1f0 ? process_one_work+0x1040/0x1040 ? process_one_work+0x1040/0x1040 kthread+0x29e/0x340 ? kthread_complete_and_exit+0x20/0x20 ret_from_fork+0x1f/0x30 </TASK> Allocated by task 154099: kasan_save_stack+0x1e/0x40 __kasan_kmalloc+0x81/0xa0 kmem_alloc+0x8d/0x2e0 [xfs] xlog_cil_init+0x1f/0x540 [xfs] xlog_alloc_log+0xd1e/0x1260 [xfs] xfs_log_mount+0xba/0x640 [xfs] xfs_mountfs+0xf2b/0x1d00 [xfs] xfs_fs_fill_super+0x10af/0x1910 [xfs] get_tree_bdev+0x383/0x670 vfs_get_tree+0x7d/0x240 path_mount+0xdb7/0x1890 __x64_sys_mount+0x1fa/0x270 do_syscall_64+0x2b/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 Freed by task 154151: kasan_save_stack+0x1e/0x40 kasan_set_track+0x21/0x30 kasan_set_free_info+0x20/0x30 ____kasan_slab_free+0x110/0x190 slab_free_freelist_hook+0xab/0x180 kfree+0xbc/0x310 xlog_dealloc_log+0x1b/0x2b0 [xfs] xfs_unmountfs+0x119/0x200 [xfs] xfs_fs_put_super+0x6e/0x2e0 [xfs] generic_shutdown_super+0x12b/0x3a0 kill_block_super+0x95/0xd0 deactivate_locked_super+0x80/0x130 cleanup_mnt+0x329/0x4d0 task_work_run+0xc5/0x160 exit_to_user_mode_prepare+0xd4/0xe0 syscall_exit_to_user_mode+0x1d/0x40 entry_SYSCALL_64_after_hwframe+0x46/0xb0 This appears to be a race between the unmount process, which frees the CIL and waits for in-flight iclog IO; and the iclog IO completion. When generic/475 runs, it starts fsstress in the background, waits a few seconds, and substitutes a dm-error device to simulate a disk falling out of a machine. If the fsstress encounters EIO on a pure data write, it will exit but the filesystem will still be online. The next thing the test does is unmount the filesystem, which tries to clean the log, free the CIL, and wait for iclog IO completion. If an iclog was being written when the dm-error switch occurred, it can race with log unmounting as follows: Thread 1 Thread 2 xfs_log_unmount xfs_log_clean xfs_log_quiesce xlog_ioend_work <observe error> xlog_force_shutdown test_and_set_bit(XLOG_IOERROR) xfs_log_force <log is shut down, nop> xfs_log_umount_write <log is shut down, nop> xlog_dealloc_log xlog_cil_destroy <wait for iclogs> spin_lock(&log->l_cilp->xc_push_lock) <KABOOM> Therefore, free the CIL after waiting for the iclogs to complete. I /think/ this race has existed for quite a few years now, though I don't remember the ~2014 era logging code well enough to know if it was a real threat then or if the actual race was exposed only more recently. Fixes: ac983517ec59 ("xfs: don't sleep in xlog_cil_force_lsn on shutdown") Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Dave Chinner <dchinner@redhat.com>
1 parent 8944c6f
ioctl.c
// SPDX-License-Identifier: GPL-2.0
/*
* linux/fs/ioctl.c
*
* Copyright (C) 1991, 1992 Linus Torvalds
*/
#include <linux/syscalls.h>
#include <linux/mm.h>
#include <linux/capability.h>
#include <linux/compat.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/security.h>
#include <linux/export.h>
#include <linux/uaccess.h>
#include <linux/writeback.h>
#include <linux/buffer_head.h>
#include <linux/falloc.h>
#include <linux/sched/signal.h>
#include <linux/fiemap.h>
#include <linux/mount.h>
#include <linux/fscrypt.h>
#include <linux/fileattr.h>
#include "internal.h"
#include <asm/ioctls.h>
/* So that the fiemap access checks can't overflow on 32 bit machines. */
#define FIEMAP_MAX_EXTENTS (UINT_MAX / sizeof(struct fiemap_extent))
/**
* vfs_ioctl - call filesystem specific ioctl methods
* @filp: open file to invoke ioctl method on
* @cmd: ioctl command to execute
* @arg: command-specific argument for ioctl
*
* Invokes filesystem specific ->unlocked_ioctl, if one exists; otherwise
* returns -ENOTTY.
*
* Returns 0 on success, -errno on error.
*/
long vfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
int error = -ENOTTY;
if (!filp->f_op->unlocked_ioctl)
goto out;
error = filp->f_op->unlocked_ioctl(filp, cmd, arg);
if (error == -ENOIOCTLCMD)
error = -ENOTTY;
out:
return error;
}
EXPORT_SYMBOL(vfs_ioctl);
static int ioctl_fibmap(struct file *filp, int __user *p)
{
struct inode *inode = file_inode(filp);
struct super_block *sb = inode->i_sb;
int error, ur_block;
sector_t block;
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
error = get_user(ur_block, p);
if (error)
return error;
if (ur_block < 0)
return -EINVAL;
block = ur_block;
error = bmap(inode, &block);
if (block > INT_MAX) {
error = -ERANGE;
pr_warn_ratelimited("[%s/%d] FS: %s File: %pD4 would truncate fibmap result\n",
current->comm, task_pid_nr(current),
sb->s_id, filp);
}
if (error)
ur_block = 0;
else
ur_block = block;
if (put_user(ur_block, p))
error = -EFAULT;
return error;
}
/**
* fiemap_fill_next_extent - Fiemap helper function
* @fieinfo: Fiemap context passed into ->fiemap
* @logical: Extent logical start offset, in bytes
* @phys: Extent physical start offset, in bytes
* @len: Extent length, in bytes
* @flags: FIEMAP_EXTENT flags that describe this extent
*
* Called from file system ->fiemap callback. Will populate extent
* info as passed in via arguments and copy to user memory. On
* success, extent count on fieinfo is incremented.
*
* Returns 0 on success, -errno on error, 1 if this was the last
* extent that will fit in user array.
*/
#define SET_UNKNOWN_FLAGS (FIEMAP_EXTENT_DELALLOC)
#define SET_NO_UNMOUNTED_IO_FLAGS (FIEMAP_EXTENT_DATA_ENCRYPTED)
#define SET_NOT_ALIGNED_FLAGS (FIEMAP_EXTENT_DATA_TAIL|FIEMAP_EXTENT_DATA_INLINE)
int fiemap_fill_next_extent(struct fiemap_extent_info *fieinfo, u64 logical,
u64 phys, u64 len, u32 flags)
{
struct fiemap_extent extent;
struct fiemap_extent __user *dest = fieinfo->fi_extents_start;
/* only count the extents */
if (fieinfo->fi_extents_max == 0) {
fieinfo->fi_extents_mapped++;
return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
}
if (fieinfo->fi_extents_mapped >= fieinfo->fi_extents_max)
return 1;
if (flags & SET_UNKNOWN_FLAGS)
flags |= FIEMAP_EXTENT_UNKNOWN;
if (flags & SET_NO_UNMOUNTED_IO_FLAGS)
flags |= FIEMAP_EXTENT_ENCODED;
if (flags & SET_NOT_ALIGNED_FLAGS)
flags |= FIEMAP_EXTENT_NOT_ALIGNED;
memset(&extent, 0, sizeof(extent));
extent.fe_logical = logical;
extent.fe_physical = phys;
extent.fe_length = len;
extent.fe_flags = flags;
dest += fieinfo->fi_extents_mapped;
if (copy_to_user(dest, &extent, sizeof(extent)))
return -EFAULT;
fieinfo->fi_extents_mapped++;
if (fieinfo->fi_extents_mapped == fieinfo->fi_extents_max)
return 1;
return (flags & FIEMAP_EXTENT_LAST) ? 1 : 0;
}
EXPORT_SYMBOL(fiemap_fill_next_extent);
/**
* fiemap_prep - 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.
* @supported_flags: Set of fiemap flags that the file system understands
*
* This function must be called from each ->fiemap instance to validate the
* fiemap request against the file system parameters.
*
* Returns 0 on success, or a negative error on failure.
*/
int fiemap_prep(struct inode *inode, struct fiemap_extent_info *fieinfo,
u64 start, u64 *len, u32 supported_flags)
{
u64 maxbytes = inode->i_sb->s_maxbytes;
u32 incompat_flags;
int ret = 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)
*len = maxbytes - start;
supported_flags |= FIEMAP_FLAG_SYNC;
supported_flags &= FIEMAP_FLAGS_COMPAT;
incompat_flags = fieinfo->fi_flags & ~supported_flags;
if (incompat_flags) {
fieinfo->fi_flags = incompat_flags;
return -EBADR;
}
if (fieinfo->fi_flags & FIEMAP_FLAG_SYNC)
ret = filemap_write_and_wait(inode->i_mapping);
return ret;
}
EXPORT_SYMBOL(fiemap_prep);
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);
int error;
if (!inode->i_op->fiemap)
return -EOPNOTSUPP;
if (copy_from_user(&fiemap, ufiemap, sizeof(fiemap)))
return -EFAULT;
if (fiemap.fm_extent_count > FIEMAP_MAX_EXTENTS)
return -EINVAL;
fieinfo.fi_flags = fiemap.fm_flags;
fieinfo.fi_extents_max = fiemap.fm_extent_count;
fieinfo.fi_extents_start = ufiemap->fm_extents;
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)))
error = -EFAULT;
return error;
}
static long ioctl_file_clone(struct file *dst_file, unsigned long srcfd,
u64 off, u64 olen, u64 destoff)
{
struct fd src_file = fdget(srcfd);
loff_t cloned;
int ret;
if (!src_file.file)
return -EBADF;
cloned = vfs_clone_file_range(src_file.file, off, dst_file, destoff,
olen, 0);
if (cloned < 0)
ret = cloned;
else if (olen && cloned != olen)
ret = -EINVAL;
else
ret = 0;
fdput(src_file);
return ret;
}
static long ioctl_file_clone_range(struct file *file,
struct file_clone_range __user *argp)
{
struct file_clone_range args;
if (copy_from_user(&args, argp, sizeof(args)))
return -EFAULT;
return ioctl_file_clone(file, args.src_fd, args.src_offset,
args.src_length, args.dest_offset);
}
/*
* This provides compatibility with legacy XFS pre-allocation ioctls
* which predate the fallocate syscall.
*
* Only the l_start, l_len and l_whence fields of the 'struct space_resv'
* are used here, rest are ignored.
*/
static int ioctl_preallocate(struct file *filp, int mode, void __user *argp)
{
struct inode *inode = file_inode(filp);
struct space_resv sr;
if (copy_from_user(&sr, argp, sizeof(sr)))
return -EFAULT;
switch (sr.l_whence) {
case SEEK_SET:
break;
case SEEK_CUR:
sr.l_start += filp->f_pos;
break;
case SEEK_END:
sr.l_start += i_size_read(inode);
break;
default:
return -EINVAL;
}
return vfs_fallocate(filp, mode | FALLOC_FL_KEEP_SIZE, sr.l_start,
sr.l_len);
}
/* on ia32 l_start is on a 32-bit boundary */
#if defined CONFIG_COMPAT && defined(CONFIG_X86_64)
/* just account for different alignment */
static int compat_ioctl_preallocate(struct file *file, int mode,
struct space_resv_32 __user *argp)
{
struct inode *inode = file_inode(file);
struct space_resv_32 sr;
if (copy_from_user(&sr, argp, sizeof(sr)))
return -EFAULT;
switch (sr.l_whence) {
case SEEK_SET:
break;
case SEEK_CUR:
sr.l_start += file->f_pos;
break;
case SEEK_END:
sr.l_start += i_size_read(inode);
break;
default:
return -EINVAL;
}
return vfs_fallocate(file, mode | FALLOC_FL_KEEP_SIZE, sr.l_start, sr.l_len);
}
#endif
static int file_ioctl(struct file *filp, unsigned int cmd, int __user *p)
{
switch (cmd) {
case FIBMAP:
return ioctl_fibmap(filp, p);
case FS_IOC_RESVSP:
case FS_IOC_RESVSP64:
return ioctl_preallocate(filp, 0, p);
case FS_IOC_UNRESVSP:
case FS_IOC_UNRESVSP64:
return ioctl_preallocate(filp, FALLOC_FL_PUNCH_HOLE, p);
case FS_IOC_ZERO_RANGE:
return ioctl_preallocate(filp, FALLOC_FL_ZERO_RANGE, p);
}
return -ENOIOCTLCMD;
}
static int ioctl_fionbio(struct file *filp, int __user *argp)
{
unsigned int flag;
int on, error;
error = get_user(on, argp);
if (error)
return error;
flag = O_NONBLOCK;
#ifdef __sparc__
/* SunOS compatibility item. */
if (O_NONBLOCK != O_NDELAY)
flag |= O_NDELAY;
#endif
spin_lock(&filp->f_lock);
if (on)
filp->f_flags |= flag;
else
filp->f_flags &= ~flag;
spin_unlock(&filp->f_lock);
return error;
}
static int ioctl_fioasync(unsigned int fd, struct file *filp,
int __user *argp)
{
unsigned int flag;
int on, error;
error = get_user(on, argp);
if (error)
return error;
flag = on ? FASYNC : 0;
/* Did FASYNC state change ? */
if ((flag ^ filp->f_flags) & FASYNC) {
if (filp->f_op->fasync)
/* fasync() adjusts filp->f_flags */
error = filp->f_op->fasync(fd, filp, on);
else
error = -ENOTTY;
}
return error < 0 ? error : 0;
}
static int ioctl_fsfreeze(struct file *filp)
{
struct super_block *sb = file_inode(filp)->i_sb;
if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
return -EPERM;
/* If filesystem doesn't support freeze feature, return. */
if (sb->s_op->freeze_fs == NULL && sb->s_op->freeze_super == NULL)
return -EOPNOTSUPP;
/* Freeze */
if (sb->s_op->freeze_super)
return sb->s_op->freeze_super(sb);
return freeze_super(sb);
}
static int ioctl_fsthaw(struct file *filp)
{
struct super_block *sb = file_inode(filp)->i_sb;
if (!ns_capable(sb->s_user_ns, CAP_SYS_ADMIN))
return -EPERM;
/* Thaw */
if (sb->s_op->thaw_super)
return sb->s_op->thaw_super(sb);
return thaw_super(sb);
}
static int ioctl_file_dedupe_range(struct file *file,
struct file_dedupe_range __user *argp)
{
struct file_dedupe_range *same = NULL;
int ret;
unsigned long size;
u16 count;
if (get_user(count, &argp->dest_count)) {
ret = -EFAULT;
goto out;
}
size = offsetof(struct file_dedupe_range, info[count]);
if (size > PAGE_SIZE) {
ret = -ENOMEM;
goto out;
}
same = memdup_user(argp, size);
if (IS_ERR(same)) {
ret = PTR_ERR(same);
same = NULL;
goto out;
}
same->dest_count = count;
ret = vfs_dedupe_file_range(file, same);
if (ret)
goto out;
ret = copy_to_user(argp, same, size);
if (ret)
ret = -EFAULT;
out:
kfree(same);
return ret;
}
/**
* fileattr_fill_xflags - initialize fileattr with xflags
* @fa: fileattr pointer
* @xflags: FS_XFLAG_* flags
*
* Set ->fsx_xflags, ->fsx_valid and ->flags (translated xflags). All
* other fields are zeroed.
*/
void fileattr_fill_xflags(struct fileattr *fa, u32 xflags)
{
memset(fa, 0, sizeof(*fa));
fa->fsx_valid = true;
fa->fsx_xflags = xflags;
if (fa->fsx_xflags & FS_XFLAG_IMMUTABLE)
fa->flags |= FS_IMMUTABLE_FL;
if (fa->fsx_xflags & FS_XFLAG_APPEND)
fa->flags |= FS_APPEND_FL;
if (fa->fsx_xflags & FS_XFLAG_SYNC)
fa->flags |= FS_SYNC_FL;
if (fa->fsx_xflags & FS_XFLAG_NOATIME)
fa->flags |= FS_NOATIME_FL;
if (fa->fsx_xflags & FS_XFLAG_NODUMP)
fa->flags |= FS_NODUMP_FL;
if (fa->fsx_xflags & FS_XFLAG_DAX)
fa->flags |= FS_DAX_FL;
if (fa->fsx_xflags & FS_XFLAG_PROJINHERIT)
fa->flags |= FS_PROJINHERIT_FL;
}
EXPORT_SYMBOL(fileattr_fill_xflags);
/**
* fileattr_fill_flags - initialize fileattr with flags
* @fa: fileattr pointer
* @flags: FS_*_FL flags
*
* Set ->flags, ->flags_valid and ->fsx_xflags (translated flags).
* All other fields are zeroed.
*/
void fileattr_fill_flags(struct fileattr *fa, u32 flags)
{
memset(fa, 0, sizeof(*fa));
fa->flags_valid = true;
fa->flags = flags;
if (fa->flags & FS_SYNC_FL)
fa->fsx_xflags |= FS_XFLAG_SYNC;
if (fa->flags & FS_IMMUTABLE_FL)
fa->fsx_xflags |= FS_XFLAG_IMMUTABLE;
if (fa->flags & FS_APPEND_FL)
fa->fsx_xflags |= FS_XFLAG_APPEND;
if (fa->flags & FS_NODUMP_FL)
fa->fsx_xflags |= FS_XFLAG_NODUMP;
if (fa->flags & FS_NOATIME_FL)
fa->fsx_xflags |= FS_XFLAG_NOATIME;
if (fa->flags & FS_DAX_FL)
fa->fsx_xflags |= FS_XFLAG_DAX;
if (fa->flags & FS_PROJINHERIT_FL)
fa->fsx_xflags |= FS_XFLAG_PROJINHERIT;
}
EXPORT_SYMBOL(fileattr_fill_flags);
/**
* vfs_fileattr_get - retrieve miscellaneous file attributes
* @dentry: the object to retrieve from
* @fa: fileattr pointer
*
* Call i_op->fileattr_get() callback, if exists.
*
* Return: 0 on success, or a negative error on failure.
*/
int vfs_fileattr_get(struct dentry *dentry, struct fileattr *fa)
{
struct inode *inode = d_inode(dentry);
if (!inode->i_op->fileattr_get)
return -ENOIOCTLCMD;
return inode->i_op->fileattr_get(dentry, fa);
}
EXPORT_SYMBOL(vfs_fileattr_get);
/**
* copy_fsxattr_to_user - copy fsxattr to userspace.
* @fa: fileattr pointer
* @ufa: fsxattr user pointer
*
* Return: 0 on success, or -EFAULT on failure.
*/
int copy_fsxattr_to_user(const struct fileattr *fa, struct fsxattr __user *ufa)
{
struct fsxattr xfa;
memset(&xfa, 0, sizeof(xfa));
xfa.fsx_xflags = fa->fsx_xflags;
xfa.fsx_extsize = fa->fsx_extsize;
xfa.fsx_nextents = fa->fsx_nextents;
xfa.fsx_projid = fa->fsx_projid;
xfa.fsx_cowextsize = fa->fsx_cowextsize;
if (copy_to_user(ufa, &xfa, sizeof(xfa)))
return -EFAULT;
return 0;
}
EXPORT_SYMBOL(copy_fsxattr_to_user);
static int copy_fsxattr_from_user(struct fileattr *fa,
struct fsxattr __user *ufa)
{
struct fsxattr xfa;
if (copy_from_user(&xfa, ufa, sizeof(xfa)))
return -EFAULT;
fileattr_fill_xflags(fa, xfa.fsx_xflags);
fa->fsx_extsize = xfa.fsx_extsize;
fa->fsx_nextents = xfa.fsx_nextents;
fa->fsx_projid = xfa.fsx_projid;
fa->fsx_cowextsize = xfa.fsx_cowextsize;
return 0;
}
/*
* Generic function to check FS_IOC_FSSETXATTR/FS_IOC_SETFLAGS values and reject
* any invalid configurations.
*
* Note: must be called with inode lock held.
*/
static int fileattr_set_prepare(struct inode *inode,
const struct fileattr *old_ma,
struct fileattr *fa)
{
int err;
/*
* The IMMUTABLE and APPEND_ONLY flags can only be changed by
* the relevant capability.
*/
if ((fa->flags ^ old_ma->flags) & (FS_APPEND_FL | FS_IMMUTABLE_FL) &&
!capable(CAP_LINUX_IMMUTABLE))
return -EPERM;
err = fscrypt_prepare_setflags(inode, old_ma->flags, fa->flags);
if (err)
return err;
/*
* Project Quota ID state is only allowed to change from within the init
* namespace. Enforce that restriction only if we are trying to change
* the quota ID state. Everything else is allowed in user namespaces.
*/
if (current_user_ns() != &init_user_ns) {
if (old_ma->fsx_projid != fa->fsx_projid)
return -EINVAL;
if ((old_ma->fsx_xflags ^ fa->fsx_xflags) &
FS_XFLAG_PROJINHERIT)
return -EINVAL;
} else {
/*
* Caller is allowed to change the project ID. If it is being
* changed, make sure that the new value is valid.
*/
if (old_ma->fsx_projid != fa->fsx_projid &&
!projid_valid(make_kprojid(&init_user_ns, fa->fsx_projid)))
return -EINVAL;
}
/* Check extent size hints. */
if ((fa->fsx_xflags & FS_XFLAG_EXTSIZE) && !S_ISREG(inode->i_mode))
return -EINVAL;
if ((fa->fsx_xflags & FS_XFLAG_EXTSZINHERIT) &&
!S_ISDIR(inode->i_mode))
return -EINVAL;
if ((fa->fsx_xflags & FS_XFLAG_COWEXTSIZE) &&
!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
return -EINVAL;
/*
* It is only valid to set the DAX flag on regular files and
* directories on filesystems.
*/
if ((fa->fsx_xflags & FS_XFLAG_DAX) &&
!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
return -EINVAL;
/* Extent size hints of zero turn off the flags. */
if (fa->fsx_extsize == 0)
fa->fsx_xflags &= ~(FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT);
if (fa->fsx_cowextsize == 0)
fa->fsx_xflags &= ~FS_XFLAG_COWEXTSIZE;
return 0;
}
/**
* vfs_fileattr_set - change miscellaneous file attributes
* @mnt_userns: user namespace of the mount
* @dentry: the object to change
* @fa: fileattr pointer
*
* After verifying permissions, call i_op->fileattr_set() callback, if
* exists.
*
* Verifying attributes involves retrieving current attributes with
* i_op->fileattr_get(), this also allows initializing attributes that have
* not been set by the caller to current values. Inode lock is held
* thoughout to prevent racing with another instance.
*
* Return: 0 on success, or a negative error on failure.
*/
int vfs_fileattr_set(struct user_namespace *mnt_userns, struct dentry *dentry,
struct fileattr *fa)
{
struct inode *inode = d_inode(dentry);
struct fileattr old_ma = {};
int err;
if (!inode->i_op->fileattr_set)
return -ENOIOCTLCMD;
if (!inode_owner_or_capable(mnt_userns, inode))
return -EPERM;
inode_lock(inode);
err = vfs_fileattr_get(dentry, &old_ma);
if (!err) {
/* initialize missing bits from old_ma */
if (fa->flags_valid) {
fa->fsx_xflags |= old_ma.fsx_xflags & ~FS_XFLAG_COMMON;
fa->fsx_extsize = old_ma.fsx_extsize;
fa->fsx_nextents = old_ma.fsx_nextents;
fa->fsx_projid = old_ma.fsx_projid;
fa->fsx_cowextsize = old_ma.fsx_cowextsize;
} else {
fa->flags |= old_ma.flags & ~FS_COMMON_FL;
}
err = fileattr_set_prepare(inode, &old_ma, fa);
if (!err)
err = inode->i_op->fileattr_set(mnt_userns, dentry, fa);
}
inode_unlock(inode);
return err;
}
EXPORT_SYMBOL(vfs_fileattr_set);
static int ioctl_getflags(struct file *file, unsigned int __user *argp)
{
struct fileattr fa = { .flags_valid = true }; /* hint only */
int err;
err = vfs_fileattr_get(file->f_path.dentry, &fa);
if (!err)
err = put_user(fa.flags, argp);
return err;
}
static int ioctl_setflags(struct file *file, unsigned int __user *argp)
{
struct user_namespace *mnt_userns = file_mnt_user_ns(file);
struct dentry *dentry = file->f_path.dentry;
struct fileattr fa;
unsigned int flags;
int err;
err = get_user(flags, argp);
if (!err) {
err = mnt_want_write_file(file);
if (!err) {
fileattr_fill_flags(&fa, flags);
err = vfs_fileattr_set(mnt_userns, dentry, &fa);
mnt_drop_write_file(file);
}
}
return err;
}
static int ioctl_fsgetxattr(struct file *file, void __user *argp)
{
struct fileattr fa = { .fsx_valid = true }; /* hint only */
int err;
err = vfs_fileattr_get(file->f_path.dentry, &fa);
if (!err)
err = copy_fsxattr_to_user(&fa, argp);
return err;
}
static int ioctl_fssetxattr(struct file *file, void __user *argp)
{
struct user_namespace *mnt_userns = file_mnt_user_ns(file);
struct dentry *dentry = file->f_path.dentry;
struct fileattr fa;
int err;
err = copy_fsxattr_from_user(&fa, argp);
if (!err) {
err = mnt_want_write_file(file);
if (!err) {
err = vfs_fileattr_set(mnt_userns, dentry, &fa);
mnt_drop_write_file(file);
}
}
return err;
}
/*
* do_vfs_ioctl() is not for drivers and not intended to be EXPORT_SYMBOL()'d.
* It's just a simple helper for sys_ioctl and compat_sys_ioctl.
*
* When you add any new common ioctls to the switches above and below,
* please ensure they have compatible arguments in compat mode.
*/
static int do_vfs_ioctl(struct file *filp, unsigned int fd,
unsigned int cmd, unsigned long arg)
{
void __user *argp = (void __user *)arg;
struct inode *inode = file_inode(filp);
switch (cmd) {
case FIOCLEX:
set_close_on_exec(fd, 1);
return 0;
case FIONCLEX:
set_close_on_exec(fd, 0);
return 0;
case FIONBIO:
return ioctl_fionbio(filp, argp);
case FIOASYNC:
return ioctl_fioasync(fd, filp, argp);
case FIOQSIZE:
if (S_ISDIR(inode->i_mode) || S_ISREG(inode->i_mode) ||
S_ISLNK(inode->i_mode)) {
loff_t res = inode_get_bytes(inode);
return copy_to_user(argp, &res, sizeof(res)) ?
-EFAULT : 0;
}
return -ENOTTY;
case FIFREEZE:
return ioctl_fsfreeze(filp);
case FITHAW:
return ioctl_fsthaw(filp);
case FS_IOC_FIEMAP:
return ioctl_fiemap(filp, argp);
case FIGETBSZ:
/* anon_bdev filesystems may not have a block size */
if (!inode->i_sb->s_blocksize)
return -EINVAL;
return put_user(inode->i_sb->s_blocksize, (int __user *)argp);
case FICLONE:
return ioctl_file_clone(filp, arg, 0, 0, 0);
case FICLONERANGE:
return ioctl_file_clone_range(filp, argp);
case FIDEDUPERANGE:
return ioctl_file_dedupe_range(filp, argp);
case FIONREAD:
if (!S_ISREG(inode->i_mode))
return vfs_ioctl(filp, cmd, arg);
return put_user(i_size_read(inode) - filp->f_pos,
(int __user *)argp);
case FS_IOC_GETFLAGS:
return ioctl_getflags(filp, argp);
case FS_IOC_SETFLAGS:
return ioctl_setflags(filp, argp);
case FS_IOC_FSGETXATTR:
return ioctl_fsgetxattr(filp, argp);
case FS_IOC_FSSETXATTR:
return ioctl_fssetxattr(filp, argp);
default:
if (S_ISREG(inode->i_mode))
return file_ioctl(filp, cmd, argp);
break;
}
return -ENOIOCTLCMD;
}
SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd, unsigned long, arg)
{
struct fd f = fdget(fd);
int error;
if (!f.file)
return -EBADF;
error = security_file_ioctl(f.file, cmd, arg);
if (error)
goto out;
error = do_vfs_ioctl(f.file, fd, cmd, arg);
if (error == -ENOIOCTLCMD)
error = vfs_ioctl(f.file, cmd, arg);
out:
fdput(f);
return error;
}
#ifdef CONFIG_COMPAT
/**
* compat_ptr_ioctl - generic implementation of .compat_ioctl file operation
*
* This is not normally called as a function, but instead set in struct
* file_operations as
*
* .compat_ioctl = compat_ptr_ioctl,
*
* On most architectures, the compat_ptr_ioctl() just passes all arguments
* to the corresponding ->ioctl handler. The exception is arch/s390, where
* compat_ptr() clears the top bit of a 32-bit pointer value, so user space
* pointers to the second 2GB alias the first 2GB, as is the case for
* native 32-bit s390 user space.
*
* The compat_ptr_ioctl() function must therefore be used only with ioctl
* functions that either ignore the argument or pass a pointer to a
* compatible data type.
*
* If any ioctl command handled by fops->unlocked_ioctl passes a plain
* integer instead of a pointer, or any of the passed data types
* is incompatible between 32-bit and 64-bit architectures, a proper
* handler is required instead of compat_ptr_ioctl.
*/
long compat_ptr_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
if (!file->f_op->unlocked_ioctl)
return -ENOIOCTLCMD;
return file->f_op->unlocked_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
}
EXPORT_SYMBOL(compat_ptr_ioctl);
COMPAT_SYSCALL_DEFINE3(ioctl, unsigned int, fd, unsigned int, cmd,
compat_ulong_t, arg)
{
struct fd f = fdget(fd);
int error;
if (!f.file)
return -EBADF;
/* RED-PEN how should LSM module know it's handling 32bit? */
error = security_file_ioctl(f.file, cmd, arg);
if (error)
goto out;
switch (cmd) {
/* FICLONE takes an int argument, so don't use compat_ptr() */
case FICLONE:
error = ioctl_file_clone(f.file, arg, 0, 0, 0);
break;
#if defined(CONFIG_X86_64)
/* these get messy on amd64 due to alignment differences */
case FS_IOC_RESVSP_32:
case FS_IOC_RESVSP64_32:
error = compat_ioctl_preallocate(f.file, 0, compat_ptr(arg));
break;
case FS_IOC_UNRESVSP_32:
case FS_IOC_UNRESVSP64_32:
error = compat_ioctl_preallocate(f.file, FALLOC_FL_PUNCH_HOLE,
compat_ptr(arg));
break;
case FS_IOC_ZERO_RANGE_32:
error = compat_ioctl_preallocate(f.file, FALLOC_FL_ZERO_RANGE,
compat_ptr(arg));
break;
#endif
/*
* These access 32-bit values anyway so no further handling is
* necessary.
*/
case FS_IOC32_GETFLAGS:
case FS_IOC32_SETFLAGS:
cmd = (cmd == FS_IOC32_GETFLAGS) ?
FS_IOC_GETFLAGS : FS_IOC_SETFLAGS;
fallthrough;
/*
* everything else in do_vfs_ioctl() takes either a compatible
* pointer argument or no argument -- call it with a modified
* argument.
*/
default:
error = do_vfs_ioctl(f.file, fd, cmd,
(unsigned long)compat_ptr(arg));
if (error != -ENOIOCTLCMD)
break;
if (f.file->f_op->compat_ioctl)
error = f.file->f_op->compat_ioctl(f.file, cmd, arg);
if (error == -ENOIOCTLCMD)
error = -ENOTTY;
break;
}
out:
fdput(f);
return error;
}
#endif
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