Signed-off-by: Ludwig Nussel <ludwig.nussel@xxxxxxx> --- Documentation/filesystems/ext2.txt | 9 ++++ fs/ext2/ext2.h | 8 +++ fs/ext2/inode.c | 48 +++++++++++++----- fs/ext2/super.c | 95 +++++++++++++++++++++++++++++++++++- 4 Dateien geändert, 147 Zeilen hinzugefügt(+), 13 Zeilen entfernt(-) diff --git a/Documentation/filesystems/ext2.txt b/Documentation/filesystems/ext2.txt index 67639f9..fcc1002 100644 --- a/Documentation/filesystems/ext2.txt +++ b/Documentation/filesystems/ext2.txt @@ -42,6 +42,15 @@ orlov (*) Use the Orlov block allocator. resuid=n The user ID which may use the reserved blocks. resgid=n The group 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. user_xattr Enable "user." POSIX Extended Attributes diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h index d9a17d0..160d5d8 100644 --- a/fs/ext2/ext2.h +++ b/fs/ext2/ext2.h @@ -84,6 +84,10 @@ struct ext2_sb_info { unsigned long 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; @@ -639,6 +643,10 @@ struct ext2_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; }; /* diff --git a/fs/ext2/inode.c b/fs/ext2/inode.c index 6363ac6..b2320e4 100644 --- a/fs/ext2/inode.c +++ b/fs/ext2/inode.c @@ -1321,8 +1321,14 @@ struct inode *ext2_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(EXT2_SB(sb)->s_uid)) + inode->i_uid = EXT2_SB(sb)->s_uid; + else + i_uid_write(inode, i_uid); + if (gid_valid(EXT2_SB(sb)->s_gid)) + inode->i_gid = EXT2_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); @@ -1426,6 +1432,10 @@ static int __ext2_write_inode(struct inode *inode, int do_sync) struct ext2_inode * raw_inode = ext2_get_inode(sb, ino, &bh); int n; int err = 0; + __le16 uid_low; + __le16 gid_low; + __le16 uid_high; + __le16 gid_high; if (IS_ERR(raw_inode)) return -EIO; @@ -1437,26 +1447,40 @@ static int __ext2_write_inode(struct inode *inode, int do_sync) ext2_get_inode_flags(ei); raw_inode->i_mode = cpu_to_le16(inode->i_mode); + if (uid_valid(EXT2_SB(sb)->s_uid)) + uid = from_kuid(&init_user_ns, EXT2_SB(sb)->s_diskuid); + if (gid_valid(EXT2_SB(sb)->s_gid)) + gid = from_kgid(&init_user_ns, EXT2_SB(sb)->s_diskgid); if (!(test_opt(sb, NO_UID32))) { - raw_inode->i_uid_low = cpu_to_le16(low_16_bits(uid)); - raw_inode->i_gid_low = cpu_to_le16(low_16_bits(gid)); + uid_low = cpu_to_le16(low_16_bits(uid)); + gid_low = cpu_to_le16(low_16_bits(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(uid)); - raw_inode->i_gid_high = cpu_to_le16(high_16_bits(gid)); + uid_high = cpu_to_le16(high_16_bits(uid)); + gid_high = cpu_to_le16(high_16_bits(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(uid)); - raw_inode->i_gid_low = cpu_to_le16(fs_high2lowgid(gid)); - raw_inode->i_uid_high = 0; - raw_inode->i_gid_high = 0; + uid_low = cpu_to_le16(fs_high2lowuid(uid)); + gid_low = cpu_to_le16(fs_high2lowgid(gid)); + uid_high = 0; + gid_high = 0; + } + /* don't mangle uid/gid of existing files if override is active */ + if (!uid_valid(EXT2_SB(sb)->s_uid) || ei->i_state & EXT2_STATE_NEW) { + raw_inode->i_uid_high = uid_high; + raw_inode->i_uid_low = uid_low; } + if (!gid_valid(EXT2_SB(sb)->s_gid) || ei->i_state & EXT2_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(inode->i_size); raw_inode->i_atime = cpu_to_le32(inode->i_atime.tv_sec); diff --git a/fs/ext2/super.c b/fs/ext2/super.c index af74d9e..0f91dfb 100644 --- a/fs/ext2/super.c +++ b/fs/ext2/super.c @@ -237,6 +237,24 @@ static int ext2_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); @@ -390,7 +408,8 @@ enum { Opt_err_ro, Opt_nouid32, Opt_nocheck, Opt_debug, Opt_oldalloc, Opt_orlov, Opt_nobh, Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl, Opt_xip, Opt_ignore, Opt_err, Opt_quota, - Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation + Opt_usrquota, Opt_grpquota, Opt_reservation, Opt_noreservation, + Opt_uid, Opt_diskuid, Opt_gid, Opt_diskgid }; static const match_table_t tokens = { @@ -424,6 +443,10 @@ static const match_table_t tokens = { {Opt_usrquota, "usrquota"}, {Opt_reservation, "reservation"}, {Opt_noreservation, "noreservation"}, + {Opt_uid, "uid=%u"}, + {Opt_diskuid, "uid=%u:%u"}, + {Opt_gid, "gid=%u"}, + {Opt_diskgid, "gid=%u:%u"}, {Opt_err, NULL} }; @@ -578,6 +601,64 @@ static int parse_options(char *options, struct super_block *sb) clear_opt(sbi->s_mount_opt, RESERVATION); ext2_msg(sb, KERN_INFO, "reservations OFF"); break; + case Opt_uid: + if (match_int(&args[0], &option)) + return 0; + uid = make_kuid(current_user_ns(), option); + if (!uid_valid(uid)) { + ext2_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)) { + ext2_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)) { + ext2_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)) { + ext2_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)) { + ext2_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)) { + ext2_msg(sb, KERN_ERR, "Invalid gid value %d", option); + return -1; + } + sbi->s_diskgid = gid; + break; case Opt_ignore: break; default: @@ -853,6 +934,10 @@ static int ext2_fill_super(struct super_block *sb, void *data, int silent) sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid)); sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid)); + sbi->s_uid = INVALID_UID; + sbi->s_gid = INVALID_GID; + sbi->s_diskuid = INVALID_UID; + sbi->s_diskgid = INVALID_GID; set_opt(sbi->s_mount_opt, RESERVATION); @@ -1256,6 +1341,10 @@ static int ext2_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; /* * Allow the "check" option to be passed as a remount option. @@ -1342,6 +1431,10 @@ 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; sb->s_flags = old_sb_flags; spin_unlock(&sbi->s_lock); return err; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html