Signed-off-by: Ludwig Nussel <ludwig.nussel@xxxxxxx> --- Documentation/filesystems/ext4.txt | 9 ++++ fs/ext4/ext4.h | 4 ++ fs/ext4/inode.c | 52 +++++++++++++++------ fs/ext4/super.c | 87 +++++++++++++++++++++++++++++++++++- 4 Dateien geändert, 137 Zeilen hinzugefügt(+), 15 Zeilen entfernt(-) diff --git a/Documentation/filesystems/ext4.txt b/Documentation/filesystems/ext4.txt index 1b7f9ac..b388ab5 100644 --- a/Documentation/filesystems/ext4.txt +++ b/Documentation/filesystems/ext4.txt @@ -245,6 +245,15 @@ 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/ext4/ext4.h b/fs/ext4/ext4.h index c3411d4..070e3ad 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1177,6 +1177,10 @@ struct ext4_sb_info { ext4_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/ext4/inode.c b/fs/ext4/inode.c index 6324f74..b02ec15 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3838,8 +3838,14 @@ struct inode *ext4_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(EXT4_SB(sb)->s_uid)) + inode->i_uid = EXT4_SB(sb)->s_uid; + else + i_uid_write(inode, i_uid); + if (gid_valid(EXT4_SB(sb)->s_gid)) + inode->i_gid = EXT4_SB(sb)->s_gid; + else + i_gid_write(inode, i_gid); set_nlink(inode, le16_to_cpu(raw_inode->i_links_count)); ext4_clear_state_flags(ei); /* Only relevant on 32-bit archs */ @@ -4054,6 +4060,10 @@ static int ext4_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; /* For fields not not tracking in the in-memory inode, * initialise them to zero for new inodes. */ @@ -4064,28 +4074,42 @@ static int ext4_do_update_inode(handle_t *handle, 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(EXT4_SB(inode->i_sb)->s_uid)) + i_uid = from_kuid(&init_user_ns, EXT4_SB(inode->i_sb)->s_diskuid); + if (gid_valid(EXT4_SB(inode->i_sb)->s_gid)) + i_gid = from_kgid(&init_user_ns, EXT4_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(EXT4_SB(inode->i_sb)->s_uid) || + ext4_test_inode_state(inode, EXT4_STATE_NEW)) { + raw_inode->i_uid_high = uid_high; + raw_inode->i_uid_low = uid_low; } + if (!gid_valid(EXT4_SB(inode->i_sb)->s_gid) || + ext4_test_inode_state(inode, EXT4_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); EXT4_INODE_SET_XTIME(i_ctime, inode, raw_inode); diff --git a/fs/ext4/super.c b/fs/ext4/super.c index d76ec82..927c020 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1229,6 +1229,7 @@ enum { Opt_inode_readahead_blks, Opt_journal_ioprio, Opt_dioread_nolock, Opt_dioread_lock, Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable, + Opt_uid, Opt_diskuid, Opt_gid, Opt_diskgid, }; static const match_table_t tokens = { @@ -1307,6 +1308,10 @@ static const match_table_t tokens = { {Opt_removed, "reservation"}, /* mount option from ext2/3 */ {Opt_removed, "noreservation"}, /* mount option from ext2/3 */ {Opt_removed, "journal=%u"}, /* mount option from ext2/3 */ + {Opt_uid, "uid=%u"}, + {Opt_diskuid, "uid=%u:%u"}, + {Opt_gid, "gid=%u"}, + {Opt_diskgid, "gid=%u:%u"}, {Opt_err, NULL}, }; @@ -1553,6 +1558,54 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token, return -1; *journal_ioprio = IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg); return 1; + case Opt_uid: + uid = make_kuid(current_user_ns(), arg); + if (!uid_valid(uid)) { + ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg); + return -1; + } + sbi->s_uid = sbi->s_diskuid = uid; + return 1; + case Opt_diskuid: + uid = make_kuid(current_user_ns(), arg); + if (!uid_valid(uid)) { + ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg); + return -1; + } + sbi->s_uid = uid; + if (match_int(&args[1], &arg)) + return -1; + uid = make_kuid(current_user_ns(), arg); + if (!uid_valid(uid)) { + ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg); + return -1; + } + sbi->s_diskuid = uid; + return 1; + case Opt_gid: + gid = make_kgid(current_user_ns(), arg); + if (!gid_valid(gid)) { + ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg); + return -1; + } + sbi->s_gid = sbi->s_diskgid = gid; + return 1; + case Opt_diskgid: + gid = make_kgid(current_user_ns(), arg); + if (!gid_valid(gid)) { + ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg); + return -1; + } + sbi->s_gid = gid; + if (match_int(&args[1], &arg)) + return -1; + gid = make_kgid(current_user_ns(), arg); + if (!gid_valid(gid)) { + ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg); + return -1; + } + sbi->s_diskgid = gid; + return 1; } for (m = ext4_mount_opts; m->token != Opt_err; m++) { @@ -1768,7 +1821,7 @@ static int _ext4_show_options(struct seq_file *seq, struct super_block *sb, char sep = nodefs ? '\n' : ','; #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep) -#define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg) +#define SEQ_OPTS_PRINT(str, args...) seq_printf(seq, "%c" str, sep, ##args) if (sbi->s_sb_block != 1) SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block); @@ -1795,6 +1848,22 @@ static int _ext4_show_options(struct seq_file *seq, struct super_block *sb, le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID) SEQ_OPTS_PRINT("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_OPTS_PRINT("uid=%u:%u", + from_kuid_munged(&init_user_ns, sbi->s_uid), + from_kuid_munged(&init_user_ns, sbi->s_diskuid)); + else + SEQ_OPTS_PRINT("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_OPTS_PRINT("gid=%u:%u", + from_kgid_munged(&init_user_ns, sbi->s_gid), + from_kgid_munged(&init_user_ns, sbi->s_diskgid)); + else + SEQ_OPTS_PRINT("gid=%u", from_kgid_munged(&init_user_ns, sbi->s_gid)); + } def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors); if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO) SEQ_OPTS_PUTS("errors=remount-ro"); @@ -3243,6 +3312,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) sbi->s_mount_opt = 0; sbi->s_resuid = make_kuid(&init_user_ns, EXT4_DEF_RESUID); sbi->s_resgid = make_kgid(&init_user_ns, EXT4_DEF_RESGID); + sbi->s_uid = INVALID_UID; + sbi->s_gid = INVALID_GID; + sbi->s_diskuid = INVALID_UID; + sbi->s_diskgid = INVALID_GID; sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS; sbi->s_sb_block = sb_block; if (sb->s_bdev->bd_part) @@ -4535,6 +4608,10 @@ struct ext4_mount_options { unsigned long s_mount_opt2; 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; u32 s_min_batch_time, s_max_batch_time; #ifdef CONFIG_QUOTA @@ -4565,6 +4642,10 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) old_opts.s_mount_opt2 = sbi->s_mount_opt2; 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; old_opts.s_min_batch_time = sbi->s_min_batch_time; old_opts.s_max_batch_time = sbi->s_max_batch_time; @@ -4732,6 +4813,10 @@ restore_opts: sbi->s_mount_opt2 = old_opts.s_mount_opt2; 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; sbi->s_min_batch_time = old_opts.s_min_batch_time; sbi->s_max_batch_time = old_opts.s_max_batch_time; -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html