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Date: Thu, 2 Aug 2012 13:54:02 +0200
From: Ludwig Nussel <ludwig.nussel@...e.de>
To: linux-kernel@...r.kernel.org
Cc: Ludwig Nussel <ludwig.nussel@...e.de>,
linux-fsdevel@...r.kernel.org,
Jan Kara <jack@...e.cz> (maintainer:EXT2 FILE SYSTEM),
Rob Landley <rob@...dley.net> (maintainer:DOCUMENTATION),
Andrew Morton <akpm@...ux-foundation.org> (maintainer:EXT3 FILE
SYSTEM),
Andreas Dilger <adilger.kernel@...ger.ca> (maintainer:EXT3 FILE
SYSTEM),
"Theodore Ts'o" <tytso@....edu> (maintainer:EXT4 FILE SYSTEM),
linux-ext4@...r.kernel.org (open list:EXT2 FILE SYSTEM),
linux-doc@...r.kernel.org (open list:DOCUMENTATION)
Subject: [PATCH 2/3] implement uid and gid mount options for ext3
Signed-off-by: Ludwig Nussel <ludwig.nussel@...e.de>
---
Documentation/filesystems/ext3.txt | 9 ++++
fs/ext3/ext3.h | 8 +++
fs/ext3/inode.c | 54 ++++++++++++++------
fs/ext3/super.c | 95 +++++++++++++++++++++++++++++++++++-
4 Dateien geändert, 149 Zeilen hinzugefügt(+), 17 Zeilen entfernt(-)
diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt
index 293855e..bd586d9 100644
--- a/Documentation/filesystems/ext3.txt
+++ b/Documentation/filesystems/ext3.txt
@@ -124,6 +124,15 @@ resgid=n The group ID which may use the reserved blocks.
resuid=n The user ID which may use the reserved blocks.
+uid=n[:m] Make all files appear to belong to uid n.
+ Useful for e.g. removable media with fstab
+ options 'user,uid=useruid'. The optional second
+ uid m is actually written to the file system.
+
+gid=n[:m] Make all files appear to belong to gid n.
+ The optional second gid m is actually written to
+ the file system.
+
sb=n Use alternate superblock at this location.
quota These options are ignored by the filesystem. They
diff --git a/fs/ext3/ext3.h b/fs/ext3/ext3.h
index e85ff15..401114d 100644
--- a/fs/ext3/ext3.h
+++ b/fs/ext3/ext3.h
@@ -245,6 +245,10 @@ struct ext3_mount_options {
unsigned long s_mount_opt;
kuid_t s_resuid;
kgid_t s_resgid;
+ kuid_t s_uid;
+ kuid_t s_diskuid;
+ kgid_t s_gid;
+ kgid_t s_diskgid;
unsigned long s_commit_interval;
#ifdef CONFIG_QUOTA
int s_jquota_fmt;
@@ -639,6 +643,10 @@ struct ext3_sb_info {
ext3_fsblk_t s_sb_block;
kuid_t s_resuid;
kgid_t s_resgid;
+ kuid_t s_uid; /* make all files appear to belong to this uid */
+ kuid_t s_diskuid; /* write this uid to disk (if s_uid != 0) */
+ kgid_t s_gid; /* make all files appear to belong to this gid */
+ kgid_t s_diskgid; /* write this gid to disk (if s_gid != 0) */
unsigned short s_mount_state;
unsigned short s_pad;
int s_addr_per_block_bits;
diff --git a/fs/ext3/inode.c b/fs/ext3/inode.c
index 9a4a5c4..c1176ae 100644
--- a/fs/ext3/inode.c
+++ b/fs/ext3/inode.c
@@ -2915,8 +2915,14 @@ struct inode *ext3_iget(struct super_block *sb, unsigned long ino)
i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16;
i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16;
}
- i_uid_write(inode, i_uid);
- i_gid_write(inode, i_gid);
+ if (uid_valid(EXT3_SB(sb)->s_uid))
+ inode->i_uid = EXT3_SB(sb)->s_uid;
+ else
+ i_uid_write(inode, i_uid);
+ if (gid_valid(EXT3_SB(sb)->s_gid))
+ inode->i_gid = EXT3_SB(sb)->s_gid;
+ else
+ i_gid_write(inode, i_gid);
set_nlink(inode, le16_to_cpu(raw_inode->i_links_count));
inode->i_size = le32_to_cpu(raw_inode->i_size);
inode->i_atime.tv_sec = (signed)le32_to_cpu(raw_inode->i_atime);
@@ -3074,6 +3080,10 @@ static int ext3_do_update_inode(handle_t *handle,
int err = 0, rc, block;
uid_t i_uid;
gid_t i_gid;
+ __le16 uid_low;
+ __le16 gid_low;
+ __le16 uid_high;
+ __le16 gid_high;
again:
/* we can't allow multiple procs in here at once, its a bit racey */
@@ -3088,30 +3098,42 @@ again:
raw_inode->i_mode = cpu_to_le16(inode->i_mode);
i_uid = i_uid_read(inode);
i_gid = i_gid_read(inode);
+ if (uid_valid(EXT3_SB(inode->i_sb)->s_uid))
+ i_uid = from_kuid(&init_user_ns, EXT3_SB(inode->i_sb)->s_diskuid);
+ if (gid_valid(EXT3_SB(inode->i_sb)->s_gid))
+ i_gid = from_kgid(&init_user_ns, EXT3_SB(inode->i_sb)->s_diskgid);
if(!(test_opt(inode->i_sb, NO_UID32))) {
- raw_inode->i_uid_low = cpu_to_le16(low_16_bits(i_uid));
- raw_inode->i_gid_low = cpu_to_le16(low_16_bits(i_gid));
+ uid_low = cpu_to_le16(low_16_bits(i_uid));
+ gid_low = cpu_to_le16(low_16_bits(i_gid));
/*
* Fix up interoperability with old kernels. Otherwise, old inodes get
* re-used with the upper 16 bits of the uid/gid intact
*/
if(!ei->i_dtime) {
- raw_inode->i_uid_high =
- cpu_to_le16(high_16_bits(i_uid));
- raw_inode->i_gid_high =
- cpu_to_le16(high_16_bits(i_gid));
+ uid_high = cpu_to_le16(high_16_bits(i_uid));
+ gid_high = cpu_to_le16(high_16_bits(i_gid));
} else {
- raw_inode->i_uid_high = 0;
- raw_inode->i_gid_high = 0;
+ uid_high = 0;
+ gid_high = 0;
}
} else {
- raw_inode->i_uid_low =
- cpu_to_le16(fs_high2lowuid(i_uid));
- raw_inode->i_gid_low =
- cpu_to_le16(fs_high2lowgid(i_gid));
- raw_inode->i_uid_high = 0;
- raw_inode->i_gid_high = 0;
+ uid_low = cpu_to_le16(fs_high2lowuid(i_uid));
+ gid_low = cpu_to_le16(fs_high2lowgid(i_gid));
+ uid_high = 0;
+ gid_high = 0;
+ }
+ /* don't mangle uid/gid of existing files if override is active */
+ if (!uid_valid(EXT3_SB(inode->i_sb)->s_uid) ||
+ ext3_test_inode_state(inode, EXT3_STATE_NEW)) {
+ raw_inode->i_uid_high = uid_high;
+ raw_inode->i_uid_low = uid_low;
}
+ if (!gid_valid(EXT3_SB(inode->i_sb)->s_gid) ||
+ ext3_test_inode_state(inode, EXT3_STATE_NEW)) {
+ raw_inode->i_gid_high = gid_high;
+ raw_inode->i_gid_low = gid_low;
+ }
+
raw_inode->i_links_count = cpu_to_le16(inode->i_nlink);
raw_inode->i_size = cpu_to_le32(ei->i_disksize);
raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec);
diff --git a/fs/ext3/super.c b/fs/ext3/super.c
index ff9bcdc..730c532 100644
--- a/fs/ext3/super.c
+++ b/fs/ext3/super.c
@@ -627,6 +627,24 @@ static int ext3_show_options(struct seq_file *seq, struct dentry *root)
seq_printf(seq, ",resgid=%u",
from_kgid_munged(&init_user_ns, sbi->s_resgid));
}
+ if (uid_valid(sbi->s_uid)) {
+ if (!uid_eq(sbi->s_uid, sbi->s_diskuid))
+ seq_printf(seq, ",uid=%u:%u",
+ from_kuid_munged(&init_user_ns, sbi->s_uid),
+ from_kuid_munged(&init_user_ns, sbi->s_diskuid));
+ else
+ seq_printf(seq, ",uid=%u",
+ from_kuid_munged(&init_user_ns, sbi->s_uid));
+ }
+ if (gid_valid(sbi->s_gid)) {
+ if (!gid_eq(sbi->s_gid, sbi->s_diskgid))
+ seq_printf(seq, ",gid=%u:%u",
+ from_kgid_munged(&init_user_ns, sbi->s_gid),
+ from_kgid_munged(&init_user_ns, sbi->s_diskgid));
+ else
+ seq_printf(seq, ",gid=%u",
+ from_kgid_munged(&init_user_ns, sbi->s_gid));
+ }
if (test_opt(sb, ERRORS_RO)) {
int def_errors = le16_to_cpu(es->s_errors);
@@ -822,7 +840,8 @@ enum {
Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
Opt_noquota, Opt_ignore, Opt_barrier, Opt_nobarrier, Opt_err,
- Opt_resize, Opt_usrquota, Opt_grpquota
+ Opt_resize, Opt_usrquota, Opt_grpquota,
+ Opt_uid, Opt_diskuid, Opt_gid, Opt_diskgid
};
static const match_table_t tokens = {
@@ -879,6 +898,10 @@ static const match_table_t tokens = {
{Opt_barrier, "barrier"},
{Opt_nobarrier, "nobarrier"},
{Opt_resize, "resize"},
+ {Opt_uid, "uid=%u"},
+ {Opt_diskuid, "uid=%u:%u"},
+ {Opt_gid, "gid=%u"},
+ {Opt_diskgid, "gid=%u:%u"},
{Opt_err, NULL},
};
@@ -1282,6 +1305,64 @@ set_qf_format:
ext3_msg(sb, KERN_WARNING,
"warning: ignoring deprecated bh option");
break;
+ case Opt_uid:
+ if (match_int(&args[0], &option))
+ return 0;
+ uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(uid)) {
+ ext3_msg(sb, KERN_ERR, "Invalid uid value %d", option);
+ return -1;
+ }
+ sbi->s_uid = sbi->s_diskuid = uid;
+ break;
+ case Opt_diskuid:
+ if (match_int(&args[0], &option))
+ return 0;
+ uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(uid)) {
+ ext3_msg(sb, KERN_ERR, "Invalid uid value %d", option);
+ return -1;
+ }
+ sbi->s_uid = uid;
+
+ if (match_int(&args[1], &option))
+ return 0;
+ uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(uid)) {
+ ext3_msg(sb, KERN_ERR, "Invalid uid value %d", option);
+ return -1;
+ }
+ sbi->s_diskuid = uid;
+ break;
+ case Opt_gid:
+ if (match_int(&args[0], &option))
+ return 0;
+ gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(gid)) {
+ ext3_msg(sb, KERN_ERR, "Invalid gid value %d", option);
+ return -1;
+ }
+ sbi->s_gid = sbi->s_diskgid = gid;
+ break;
+ case Opt_diskgid:
+ if (match_int(&args[0], &option))
+ return 0;
+ gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(gid)) {
+ ext3_msg(sb, KERN_ERR, "Invalid gid value %d", option);
+ return -1;
+ }
+ sbi->s_gid = gid;
+
+ if (match_int(&args[1], &option))
+ return 0;
+ gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(gid)) {
+ ext3_msg(sb, KERN_ERR, "Invalid gid value %d", option);
+ return -1;
+ }
+ sbi->s_diskgid = gid;
+ break;
default:
ext3_msg(sb, KERN_ERR,
"error: unrecognized mount option \"%s\" "
@@ -1668,6 +1749,10 @@ static int ext3_fill_super (struct super_block *sb, void *data, int silent)
sbi->s_mount_opt = 0;
sbi->s_resuid = make_kuid(&init_user_ns, EXT3_DEF_RESUID);
sbi->s_resgid = make_kgid(&init_user_ns, EXT3_DEF_RESGID);
+ sbi->s_uid = INVALID_UID;
+ sbi->s_gid = INVALID_GID;
+ sbi->s_diskuid = INVALID_UID;
+ sbi->s_diskgid = INVALID_GID;
sbi->s_sb_block = sb_block;
blocksize = sb_min_blocksize(sb, EXT3_MIN_BLOCK_SIZE);
@@ -2611,6 +2696,10 @@ static int ext3_remount (struct super_block * sb, int * flags, char * data)
old_opts.s_mount_opt = sbi->s_mount_opt;
old_opts.s_resuid = sbi->s_resuid;
old_opts.s_resgid = sbi->s_resgid;
+ old_opts.s_uid = sbi->s_uid;
+ old_opts.s_diskuid = sbi->s_diskuid;
+ old_opts.s_gid = sbi->s_gid;
+ old_opts.s_diskgid = sbi->s_diskgid;
old_opts.s_commit_interval = sbi->s_commit_interval;
#ifdef CONFIG_QUOTA
old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
@@ -2722,6 +2811,10 @@ restore_opts:
sbi->s_mount_opt = old_opts.s_mount_opt;
sbi->s_resuid = old_opts.s_resuid;
sbi->s_resgid = old_opts.s_resgid;
+ sbi->s_uid = old_opts.s_uid;
+ sbi->s_diskuid = old_opts.s_diskuid;
+ sbi->s_gid = old_opts.s_gid;
+ sbi->s_diskgid = old_opts.s_diskgid;
sbi->s_commit_interval = old_opts.s_commit_interval;
#ifdef CONFIG_QUOTA
sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
--
1.7.10.4
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