From: Ludwig Nussel Subject: [PATCH 2/3] implement uid and gid mount options for ext3 Date: Fri, 11 May 2012 13:10:07 +0200 Message-ID: <1336734608-15157-3-git-send-email-ludwig.nussel@suse.de> References: <1336660924-9598-1-git-send-email-ludwig.nussel@suse.d> <1336734608-15157-1-git-send-email-ludwig.nussel@suse.de> Cc: Ludwig Nussel , linux-fsdevel@vger.kernel.org, Jan Kara (maintainer:EXT2 FILE SYSTEM), Rob Landley (maintainer:DOCUMENTATION), Andrew Morton (maintainer:EXT3 FILE SYSTEM), Andreas Dilger (maintainer:EXT3 FILE SYSTEM), "Theodore Ts'o" (maintainer:EXT4 FILE SYSTEM), linux-ext4@vger.kernel.org (open list:EXT2 FILE SYSTEM), linux-doc@vger.kernel.org (open list:DOCUMENTATION) To: linux-kernel@vger.kernel.org Return-path: In-Reply-To: <1336734608-15157-1-git-send-email-ludwig.nussel@suse.de> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Signed-off-by: Ludwig Nussel --- Documentation/filesystems/ext3.txt | 9 ++++++ fs/ext3/ext3.h | 8 +++++ fs/ext3/inode.c | 50 ++++++++++++++++++++++--------- fs/ext3/super.c | 57 +++++++++++++++++++++++++++++++++++- 4 files changed, 109 insertions(+), 15 deletions(-) diff --git a/Documentation/filesystems/ext3.txt b/Documentation/filesystems/ext3.txt index b100adc..b2407a7 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 b6515fd..c7c4578 100644 --- a/fs/ext3/ext3.h +++ b/fs/ext3/ext3.h @@ -245,6 +245,10 @@ struct ext3_mount_options { unsigned long s_mount_opt; uid_t s_resuid; gid_t s_resgid; + uid_t s_uid; + uid_t s_diskuid; + gid_t s_gid; + gid_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; uid_t s_resuid; gid_t s_resgid; + uid_t s_uid; /* make all files appear to belong to this uid */ + uid_t s_diskuid; /* write this uid to disk (if s_uid != 0) */ + gid_t s_gid; /* make all files appear to belong to this gid */ + gid_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 10d7812..095bd31 100644 --- a/fs/ext3/inode.c +++ b/fs/ext3/inode.c @@ -2913,6 +2913,10 @@ struct inode *ext3_iget(struct super_block *sb, unsigned long ino) inode->i_uid |= le16_to_cpu(raw_inode->i_uid_high) << 16; inode->i_gid |= le16_to_cpu(raw_inode->i_gid_high) << 16; } + if (EXT3_SB(sb)->s_uid) + inode->i_uid = EXT3_SB(sb)->s_uid; + if (EXT3_SB(sb)->s_gid) + inode->i_gid = EXT3_SB(sb)->s_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); @@ -3066,8 +3070,14 @@ static int ext3_do_update_inode(handle_t *handle, { struct ext3_inode *raw_inode = ext3_raw_inode(iloc); struct ext3_inode_info *ei = EXT3_I(inode); + uid_t uid = inode->i_uid; + gid_t gid = inode->i_gid; struct buffer_head *bh = iloc->bh; int err = 0, rc, block; + __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 */ @@ -3080,30 +3090,42 @@ again: ext3_get_inode_flags(ei); raw_inode->i_mode = cpu_to_le16(inode->i_mode); + if (EXT3_SB(inode->i_sb)->s_uid) + uid = EXT3_SB(inode->i_sb)->s_diskuid; + if (EXT3_SB(inode->i_sb)->s_gid) + gid = 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(inode->i_uid)); - raw_inode->i_gid_low = cpu_to_le16(low_16_bits(inode->i_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(inode->i_uid)); - raw_inode->i_gid_high = - cpu_to_le16(high_16_bits(inode->i_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(inode->i_uid)); - raw_inode->i_gid_low = - cpu_to_le16(fs_high2lowgid(inode->i_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 (!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 (!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 cf0b592..4dcce09 100644 --- a/fs/ext3/super.c +++ b/fs/ext3/super.c @@ -625,6 +625,20 @@ static int ext3_show_options(struct seq_file *seq, struct dentry *root) le16_to_cpu(es->s_def_resgid) != EXT3_DEF_RESGID) { seq_printf(seq, ",resgid=%u", sbi->s_resgid); } + if (sbi->s_uid) { + if (sbi->s_uid != sbi->s_diskuid) + seq_printf(seq, ",uid=%u:%u", + sbi->s_uid, sbi->s_diskuid); + else + seq_printf(seq, ",uid=%u", sbi->s_uid); + } + if (sbi->s_gid) { + if (sbi->s_gid != sbi->s_diskgid) + seq_printf(seq, ",gid=%u:%u", + sbi->s_gid, sbi->s_diskgid); + else + seq_printf(seq, ",gid=%u", sbi->s_gid); + } if (test_opt(sb, ERRORS_RO)) { int def_errors = le16_to_cpu(es->s_errors); @@ -820,7 +834,8 @@ 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 = { @@ -877,6 +892,10 @@ 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}, }; @@ -1267,6 +1286,34 @@ 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; + sbi->s_uid = sbi->s_diskuid = option; + break; + case Opt_diskuid: + if (match_int(&args[0], &option)) + return 0; + sbi->s_uid = option; + + if (match_int(&args[1], &option)) + return 0; + sbi->s_diskuid = option; + break; + case Opt_gid: + if (match_int(&args[0], &option)) + return 0; + sbi->s_gid = sbi->s_diskgid = option; + break; + case Opt_diskgid: + if (match_int(&args[0], &option)) + return 0; + sbi->s_gid = option; + + if (match_int(&args[1], &option)) + return 0; + sbi->s_diskgid = option; + break; default: ext3_msg(sb, KERN_ERR, "error: unrecognized mount option \"%s\" " @@ -2590,6 +2637,10 @@ 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; @@ -2701,6 +2752,10 @@ 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; -- 1.7.7