| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Wed, 03 Jul 2013 12:22:33 +0900
From: OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
To: bintian.wang@...aro.org
Cc: linux-kernel@...r.kernel.org, Mike Lockwood <lockwood@...roid.com>,
dmitry pervushin <dpervushin@...il.com>,
Colin Cross <ccross@...roid.com>,
Android Kernel Team <kernel-team@...roid.com>,
Andrew Morton <akpm@...ux-foundation.org>,
John Stultz <john.stultz@...aro.org>,
Sean McNeil <sean@...eil.com>
Subject: Re: [PATCH RFC] Add FAT_IOCTL_GET_VOLUME_ID
bintian.wang@...aro.org writes:
> From: Mike Lockwood <lockwood@...roid.com>
>
> This patch, originally from Android kernel, adds vfat ioctl command
> FAT_IOCTL_GET_VOLUME_ID, with this command we can get the vfat volume ID using
> following code:
>
> ioctl(fd, FAT_IOCTL_GET_VOLUME_ID, &volume_ID)
>
> This patch is a modified version of the patch by Mike Lockwood, with changes
> from Dmitry Pervushin, who noticed the original patch makes some volume IDs
> abiguous with error returns: for example, if volume id is 0xFFFFFDAD, that
> matches -ENOIOCTLCMD, we get "FFFFFFFF" from the user space.
>
> So add a parameter to ioctl to get the correct volume ID.
>
> Android uses vfat volume ID to identify different sd card, when a new sd card
> is inserted to device, android can scan the media on it and pop up new contents.
Acked-by: OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
Thanks.
> Cc: dmitry pervushin <dpervushin@...il.com>
> Cc: Mike Lockwood <lockwood@...roid.com>
> Cc: Colin Cross <ccross@...roid.com>
> Cc: Android Kernel Team <kernel-team@...roid.com>
> Cc: OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
> Cc: Andrew Morton <akpm@...ux-foundation.org>
> Cc: John Stultz <john.stultz@...aro.org>
> Cc: Sean McNeil <sean@...eil.com>
>
> Signed-off-by: Bintian Wang <bintian.wang@...aro.org>
> ---
> fs/fat/fat.h | 1 +
> fs/fat/file.c | 8 ++++++++
> fs/fat/inode.c | 12 ++++++++++++
> include/uapi/linux/msdos_fs.h | 10 ++++++++++
> 4 files changed, 31 insertions(+)
>
> diff --git a/fs/fat/fat.h b/fs/fat/fat.h
> index 21664fc..4241e6f 100644
> --- a/fs/fat/fat.h
> +++ b/fs/fat/fat.h
> @@ -86,6 +86,7 @@ struct msdos_sb_info {
> const void *dir_ops; /* Opaque; default directory operations */
> int dir_per_block; /* dir entries per block */
> int dir_per_block_bits; /* log2(dir_per_block) */
> + unsigned int vol_id; /*volume ID*/
>
> int fatent_shift;
> struct fatent_operations *fatent_ops;
> diff --git a/fs/fat/file.c b/fs/fat/file.c
> index b0b632e..9b104f5 100644
> --- a/fs/fat/file.c
> +++ b/fs/fat/file.c
> @@ -114,6 +114,12 @@ out:
> return err;
> }
>
> +static int fat_ioctl_get_volume_id(struct inode *inode, u32 __user *user_attr)
> +{
> + struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
> + return put_user(sbi->vol_id, user_attr);
> +}
> +
> long fat_generic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> {
> struct inode *inode = file_inode(filp);
> @@ -124,6 +130,8 @@ long fat_generic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
> return fat_ioctl_get_attributes(inode, user_attr);
> case FAT_IOCTL_SET_ATTRIBUTES:
> return fat_ioctl_set_attributes(filp, user_attr);
> + case FAT_IOCTL_GET_VOLUME_ID:
> + return fat_ioctl_get_volume_id(inode, user_attr);
> default:
> return -ENOTTY; /* Inappropriate ioctl for device */
> }
> diff --git a/fs/fat/inode.c b/fs/fat/inode.c
> index 5d4513c..11b51bb 100644
> --- a/fs/fat/inode.c
> +++ b/fs/fat/inode.c
> @@ -1415,6 +1415,18 @@ int fat_fill_super(struct super_block *sb, void *data, int silent, int isvfat,
> brelse(fsinfo_bh);
> }
>
> + /* interpret volume ID as a little endian 32 bit integer */
> + if (sbi->fat_bits == 32)
> + sbi->vol_id = (((u32)b->fat32.vol_id[0]) |
> + ((u32)b->fat32.vol_id[1] << 8) |
> + ((u32)b->fat32.vol_id[2] << 16) |
> + ((u32)b->fat32.vol_id[3] << 24));
> + else /* fat 16 or 12 */
> + sbi->vol_id = (((u32)b->fat16.vol_id[0]) |
> + ((u32)b->fat16.vol_id[1] << 8) |
> + ((u32)b->fat16.vol_id[2] << 16) |
> + ((u32)b->fat16.vol_id[3] << 24));
> +
> sbi->dir_per_block = sb->s_blocksize / sizeof(struct msdos_dir_entry);
> sbi->dir_per_block_bits = ffs(sbi->dir_per_block) - 1;
>
> diff --git a/include/uapi/linux/msdos_fs.h b/include/uapi/linux/msdos_fs.h
> index f055e58..e284ff9 100644
> --- a/include/uapi/linux/msdos_fs.h
> +++ b/include/uapi/linux/msdos_fs.h
> @@ -104,6 +104,8 @@ struct __fat_dirent {
> /* <linux/videotext.h> has used 0x72 ('r') in collision, so skip a few */
> #define FAT_IOCTL_GET_ATTRIBUTES _IOR('r', 0x10, __u32)
> #define FAT_IOCTL_SET_ATTRIBUTES _IOW('r', 0x11, __u32)
> +/*Android kernel has used 0x12, so we use 0x13*/
> +#define FAT_IOCTL_GET_VOLUME_ID _IOR('r', 0x13, __u32)
>
> struct fat_boot_sector {
> __u8 ignored[3]; /* Boot strap short or near jump */
> @@ -128,6 +130,10 @@ struct fat_boot_sector {
> __u8 drive_number; /* Physical drive number */
> __u8 state; /* undocumented, but used
> for mount state. */
> + __u8 signature; /* extended boot signature */
> + __u8 vol_id[4]; /* volume ID */
> + __u8 vol_label[11]; /* volume label */
> + __u8 fs_type[8]; /* file system type */
> /* other fiealds are not added here */
> } fat16;
>
> @@ -147,6 +153,10 @@ struct fat_boot_sector {
> __u8 drive_number; /* Physical drive number */
> __u8 state; /* undocumented, but used
> for mount state. */
> + __u8 signature; /* extended boot signature */
> + __u8 vol_id[4]; /* volume ID */
> + __u8 vol_label[11]; /* volume label */
> + __u8 fs_type[8]; /* file system type */
> /* other fiealds are not added here */
> } fat32;
> };
--
OGAWA Hirofumi <hirofumi@...l.parknet.co.jp>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists