Message ID | 20200406115835.1150002-3-hch@lst.de (mailing list archive) |
---|---|
State | Mainlined, archived |
Headers | show |
Series | [1/2] PM / sleep: move SNAPSHOT_SET_SWAP_AREA handling into a helper | expand |
On Mon, Apr 6, 2020 at 1:58 PM Christoph Hellwig <hch@lst.de> wrote: > > Use in_compat_syscall to copy directly from the 32-bit ABI structure. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > kernel/power/user.c | 54 ++++++++++++++++++--------------------------- > 1 file changed, 22 insertions(+), 32 deletions(-) > > diff --git a/kernel/power/user.c b/kernel/power/user.c > index 0cb555f526e4..7959449765d9 100644 > --- a/kernel/power/user.c > +++ b/kernel/power/user.c > @@ -196,28 +196,44 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, > return res; > } > > +struct compat_resume_swap_area { > + compat_loff_t offset; > + u32 dev; > +} __packed; > + > static int snapshot_set_swap_area(struct snapshot_data *data, > void __user *argp) > { > - struct resume_swap_area swap_area; > sector_t offset; > dev_t swdev; > > if (swsusp_swap_in_use()) > return -EPERM; > - if (copy_from_user(&swap_area, argp, sizeof(swap_area))) > - return -EFAULT; > + > + if (in_compat_syscall()) { > + struct compat_resume_swap_area swap_area; > + > + if (copy_from_user(&swap_area, argp, sizeof(swap_area))) > + return -EFAULT; > + swdev = new_decode_dev(swap_area.dev); > + offset = swap_area.offset; > + } else { > + struct resume_swap_area swap_area; > + > + if (copy_from_user(&swap_area, argp, sizeof(swap_area))) > + return -EFAULT; > + swdev = new_decode_dev(swap_area.dev); > + offset = swap_area.offset; > + } > > /* > * User space encodes device types as two-byte values, > * so we need to recode them > */ > - swdev = new_decode_dev(swap_area.dev); > if (!swdev) { > data->swap = -1; > return -EINVAL; > } > - offset = swap_area.offset; > data->swap = swap_type_of(swdev, offset, NULL); > if (data->swap < 0) > return -ENODEV; > @@ -394,12 +410,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, > } > > #ifdef CONFIG_COMPAT > - > -struct compat_resume_swap_area { > - compat_loff_t offset; > - u32 dev; > -} __packed; > - > static long > snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > { > @@ -410,33 +420,13 @@ snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) > case SNAPSHOT_AVAIL_SWAP_SIZE: > case SNAPSHOT_ALLOC_SWAP_PAGE: > case SNAPSHOT_CREATE_IMAGE: > + case SNAPSHOT_SET_SWAP_AREA: > return snapshot_ioctl(file, cmd, > (unsigned long) compat_ptr(arg)); > - > - case SNAPSHOT_SET_SWAP_AREA: { > - struct compat_resume_swap_area __user *u_swap_area = > - compat_ptr(arg); > - struct resume_swap_area swap_area; > - mm_segment_t old_fs; > - int err; > - > - err = get_user(swap_area.offset, &u_swap_area->offset); > - err |= get_user(swap_area.dev, &u_swap_area->dev); > - if (err) > - return -EFAULT; > - old_fs = get_fs(); > - set_fs(KERNEL_DS); > - err = snapshot_ioctl(file, SNAPSHOT_SET_SWAP_AREA, > - (unsigned long) &swap_area); > - set_fs(old_fs); > - return err; > - } > - > default: > return snapshot_ioctl(file, cmd, arg); > } > } > - > #endif /* CONFIG_COMPAT */ > > static const struct file_operations snapshot_fops = { > -- Applied along with the [1/2] as 5.7-rc material, thanks!
diff --git a/kernel/power/user.c b/kernel/power/user.c index 0cb555f526e4..7959449765d9 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -196,28 +196,44 @@ static ssize_t snapshot_write(struct file *filp, const char __user *buf, return res; } +struct compat_resume_swap_area { + compat_loff_t offset; + u32 dev; +} __packed; + static int snapshot_set_swap_area(struct snapshot_data *data, void __user *argp) { - struct resume_swap_area swap_area; sector_t offset; dev_t swdev; if (swsusp_swap_in_use()) return -EPERM; - if (copy_from_user(&swap_area, argp, sizeof(swap_area))) - return -EFAULT; + + if (in_compat_syscall()) { + struct compat_resume_swap_area swap_area; + + if (copy_from_user(&swap_area, argp, sizeof(swap_area))) + return -EFAULT; + swdev = new_decode_dev(swap_area.dev); + offset = swap_area.offset; + } else { + struct resume_swap_area swap_area; + + if (copy_from_user(&swap_area, argp, sizeof(swap_area))) + return -EFAULT; + swdev = new_decode_dev(swap_area.dev); + offset = swap_area.offset; + } /* * User space encodes device types as two-byte values, * so we need to recode them */ - swdev = new_decode_dev(swap_area.dev); if (!swdev) { data->swap = -1; return -EINVAL; } - offset = swap_area.offset; data->swap = swap_type_of(swdev, offset, NULL); if (data->swap < 0) return -ENODEV; @@ -394,12 +410,6 @@ static long snapshot_ioctl(struct file *filp, unsigned int cmd, } #ifdef CONFIG_COMPAT - -struct compat_resume_swap_area { - compat_loff_t offset; - u32 dev; -} __packed; - static long snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -410,33 +420,13 @@ snapshot_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) case SNAPSHOT_AVAIL_SWAP_SIZE: case SNAPSHOT_ALLOC_SWAP_PAGE: case SNAPSHOT_CREATE_IMAGE: + case SNAPSHOT_SET_SWAP_AREA: return snapshot_ioctl(file, cmd, (unsigned long) compat_ptr(arg)); - - case SNAPSHOT_SET_SWAP_AREA: { - struct compat_resume_swap_area __user *u_swap_area = - compat_ptr(arg); - struct resume_swap_area swap_area; - mm_segment_t old_fs; - int err; - - err = get_user(swap_area.offset, &u_swap_area->offset); - err |= get_user(swap_area.dev, &u_swap_area->dev); - if (err) - return -EFAULT; - old_fs = get_fs(); - set_fs(KERNEL_DS); - err = snapshot_ioctl(file, SNAPSHOT_SET_SWAP_AREA, - (unsigned long) &swap_area); - set_fs(old_fs); - return err; - } - default: return snapshot_ioctl(file, cmd, arg); } } - #endif /* CONFIG_COMPAT */ static const struct file_operations snapshot_fops = {
Use in_compat_syscall to copy directly from the 32-bit ABI structure. Signed-off-by: Christoph Hellwig <hch@lst.de> --- kernel/power/user.c | 54 ++++++++++++++++++--------------------------- 1 file changed, 22 insertions(+), 32 deletions(-)