From 421a989cdb855db7ca72e35a1cc093169179d5c3 Mon Sep 17 00:00:00 2001 From: Daniel Rosenberg Date: Tue, 2 Jan 2018 14:44:49 -0800 Subject: [PATCH] ANDROID: sdcardfs: Add default_normal option The default_normal option causes mounts with the gid set to AID_SDCARD_RW to have user specific gids, as in the normal case. Signed-off-by: Daniel Rosenberg Change-Id: I9619b8ac55f41415df943484dc8db1ea986cef6f Bug: 64672411 --- fs/sdcardfs/inode.c | 7 ++++--- fs/sdcardfs/main.c | 7 +++++++ fs/sdcardfs/sdcardfs.h | 9 ++++++--- fs/sdcardfs/super.c | 2 ++ 4 files changed, 19 insertions(+), 6 deletions(-) diff --git a/fs/sdcardfs/inode.c b/fs/sdcardfs/inode.c index 5e919e2956e0..c3763c50b018 100644 --- a/fs/sdcardfs/inode.c +++ b/fs/sdcardfs/inode.c @@ -648,7 +648,7 @@ static int sdcardfs_permission(struct vfsmount *mnt, struct inode *inode, int ma */ copy_attrs(&tmp, inode); tmp.i_uid = make_kuid(&init_user_ns, top->d_uid); - tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, top)); + tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, inode->i_sb, top)); tmp.i_mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(inode), top); data_put(top); @@ -727,7 +727,7 @@ static int sdcardfs_setattr(struct vfsmount *mnt, struct dentry *dentry, struct */ copy_attrs(&tmp, inode); tmp.i_uid = make_kuid(&init_user_ns, top->d_uid); - tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, top)); + tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, dentry->d_sb, top)); tmp.i_mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(inode), top); tmp.i_size = i_size_read(inode); @@ -829,6 +829,7 @@ static int sdcardfs_fillattr(struct vfsmount *mnt, { struct sdcardfs_inode_info *info = SDCARDFS_I(inode); struct sdcardfs_inode_data *top = top_data_get(info); + struct super_block *sb = inode->i_sb; if (!top) return -EINVAL; @@ -838,7 +839,7 @@ static int sdcardfs_fillattr(struct vfsmount *mnt, stat->mode = (inode->i_mode & S_IFMT) | get_mode(mnt, info, top); stat->nlink = inode->i_nlink; stat->uid = make_kuid(&init_user_ns, top->d_uid); - stat->gid = make_kgid(&init_user_ns, get_gid(mnt, top)); + stat->gid = make_kgid(&init_user_ns, get_gid(mnt, sb, top)); stat->rdev = inode->i_rdev; stat->size = i_size_read(inode); stat->atime = inode->i_atime; diff --git a/fs/sdcardfs/main.c b/fs/sdcardfs/main.c index 0a2b5167e9a2..ac27bb301c5e 100644 --- a/fs/sdcardfs/main.c +++ b/fs/sdcardfs/main.c @@ -33,6 +33,7 @@ enum { Opt_userid, Opt_reserved_mb, Opt_gid_derivation, + Opt_default_normal, Opt_err, }; @@ -45,6 +46,7 @@ static const match_table_t sdcardfs_tokens = { {Opt_userid, "userid=%d"}, {Opt_multiuser, "multiuser"}, {Opt_gid_derivation, "derive_gid"}, + {Opt_default_normal, "default_normal"}, {Opt_reserved_mb, "reserved_mb=%u"}, {Opt_err, NULL} }; @@ -68,6 +70,7 @@ static int parse_options(struct super_block *sb, char *options, int silent, opts->reserved_mb = 0; /* by default, gid derivation is off */ opts->gid_derivation = false; + opts->default_normal = false; *debug = 0; @@ -122,6 +125,9 @@ static int parse_options(struct super_block *sb, char *options, int silent, case Opt_gid_derivation: opts->gid_derivation = true; break; + case Opt_default_normal: + opts->default_normal = true; + break; /* unknown option */ default: if (!silent) @@ -175,6 +181,7 @@ int parse_options_remount(struct super_block *sb, char *options, int silent, return 0; vfsopts->mask = option; break; + case Opt_default_normal: case Opt_multiuser: case Opt_userid: case Opt_fsuid: diff --git a/fs/sdcardfs/sdcardfs.h b/fs/sdcardfs/sdcardfs.h index d1d8bab00fe5..3da9fe94b772 100644 --- a/fs/sdcardfs/sdcardfs.h +++ b/fs/sdcardfs/sdcardfs.h @@ -220,6 +220,7 @@ struct sdcardfs_mount_options { userid_t fs_user_id; bool multiuser; bool gid_derivation; + bool default_normal; unsigned int reserved_mb; }; @@ -413,11 +414,13 @@ static inline void set_top(struct sdcardfs_inode_info *info, } static inline int get_gid(struct vfsmount *mnt, + struct super_block *sb, struct sdcardfs_inode_data *data) { - struct sdcardfs_vfsmount_options *opts = mnt->data; + struct sdcardfs_vfsmount_options *vfsopts = mnt->data; + struct sdcardfs_sb_info *sbi = SDCARDFS_SB(sb); - if (opts->gid == AID_SDCARD_RW) + if (vfsopts->gid == AID_SDCARD_RW && !sbi->options.default_normal) /* As an optimization, certain trusted system components only run * as owner but operate across all users. Since we're now handing * out the sdcard_rw GID only to trusted apps, we're okay relaxing @@ -426,7 +429,7 @@ static inline int get_gid(struct vfsmount *mnt, */ return AID_SDCARD_RW; else - return multiuser_get_uid(data->userid, opts->gid); + return multiuser_get_uid(data->userid, vfsopts->gid); } static inline int get_mode(struct vfsmount *mnt, diff --git a/fs/sdcardfs/super.c b/fs/sdcardfs/super.c index b89947d878e3..87d6f836592e 100644 --- a/fs/sdcardfs/super.c +++ b/fs/sdcardfs/super.c @@ -304,6 +304,8 @@ static int sdcardfs_show_options(struct vfsmount *mnt, struct seq_file *m, seq_printf(m, ",userid=%u", opts->fs_user_id); if (opts->gid_derivation) seq_puts(m, ",derive_gid"); + if (opts->default_normal) + seq_puts(m, ",default_normal"); if (opts->reserved_mb != 0) seq_printf(m, ",reserved=%uMB", opts->reserved_mb); -- 2.11.0