diff options
Diffstat (limited to 'fs/sdcardfs')
| -rw-r--r-- | fs/sdcardfs/dentry.c | 17 | ||||
| -rw-r--r-- | fs/sdcardfs/derived_perm.c | 130 | ||||
| -rw-r--r-- | fs/sdcardfs/inode.c | 53 | ||||
| -rw-r--r-- | fs/sdcardfs/lookup.c | 5 | ||||
| -rw-r--r-- | fs/sdcardfs/main.c | 8 | ||||
| -rw-r--r-- | fs/sdcardfs/packagelist.c | 2 | ||||
| -rw-r--r-- | fs/sdcardfs/sdcardfs.h | 114 | ||||
| -rw-r--r-- | fs/sdcardfs/super.c | 49 |
8 files changed, 239 insertions, 139 deletions
diff --git a/fs/sdcardfs/dentry.c b/fs/sdcardfs/dentry.c index 7a19e77fce99..13da7e5245bd 100644 --- a/fs/sdcardfs/dentry.c +++ b/fs/sdcardfs/dentry.c @@ -34,6 +34,8 @@ static int sdcardfs_d_revalidate(struct dentry *dentry, unsigned int flags) struct dentry *parent_lower_dentry = NULL; struct dentry *lower_cur_parent_dentry = NULL; struct dentry *lower_dentry = NULL; + struct inode *inode; + struct sdcardfs_inode_data *data; if (flags & LOOKUP_RCU) return -ECHILD; @@ -103,6 +105,21 @@ static int sdcardfs_d_revalidate(struct dentry *dentry, unsigned int flags) spin_unlock(&dentry->d_lock); spin_unlock(&lower_dentry->d_lock); } + if (!err) + goto out; + + /* If our top's inode is gone, we may be out of date */ + inode = igrab(d_inode(dentry)); + if (inode) { + data = top_data_get(SDCARDFS_I(inode)); + if (!data || data->abandoned) { + d_drop(dentry); + err = 0; + } + if (data) + data_put(data); + iput(inode); + } out: dput(parent_dentry); diff --git a/fs/sdcardfs/derived_perm.c b/fs/sdcardfs/derived_perm.c index b4595aab5713..85a60fb5ff39 100644 --- a/fs/sdcardfs/derived_perm.c +++ b/fs/sdcardfs/derived_perm.c @@ -26,28 +26,28 @@ static void inherit_derived_state(struct inode *parent, struct inode *child) struct sdcardfs_inode_info *pi = SDCARDFS_I(parent); struct sdcardfs_inode_info *ci = SDCARDFS_I(child); - ci->perm = PERM_INHERIT; - ci->userid = pi->userid; - ci->d_uid = pi->d_uid; - ci->under_android = pi->under_android; - ci->under_cache = pi->under_cache; - ci->under_obb = pi->under_obb; - set_top(ci, pi->top); + ci->data->perm = PERM_INHERIT; + ci->data->userid = pi->data->userid; + ci->data->d_uid = pi->data->d_uid; + ci->data->under_android = pi->data->under_android; + ci->data->under_cache = pi->data->under_cache; + ci->data->under_obb = pi->data->under_obb; + set_top(ci, pi->top_data); } /* helper function for derived state */ void setup_derived_state(struct inode *inode, perm_t perm, userid_t userid, - uid_t uid, bool under_android, - struct inode *top) + uid_t uid, bool under_android, + struct sdcardfs_inode_data *top) { struct sdcardfs_inode_info *info = SDCARDFS_I(inode); - info->perm = perm; - info->userid = userid; - info->d_uid = uid; - info->under_android = under_android; - info->under_cache = false; - info->under_obb = false; + info->data->perm = perm; + info->data->userid = userid; + info->data->d_uid = uid; + info->data->under_android = under_android; + info->data->under_cache = false; + info->data->under_obb = false; set_top(info, top); } @@ -58,7 +58,8 @@ void get_derived_permission_new(struct dentry *parent, struct dentry *dentry, const struct qstr *name) { struct sdcardfs_inode_info *info = SDCARDFS_I(d_inode(dentry)); - struct sdcardfs_inode_info *parent_info = SDCARDFS_I(d_inode(parent)); + struct sdcardfs_inode_data *parent_data = + SDCARDFS_I(d_inode(parent))->data; appid_t appid; unsigned long user_num; int err; @@ -82,60 +83,61 @@ void get_derived_permission_new(struct dentry *parent, struct dentry *dentry, if (!S_ISDIR(d_inode(dentry)->i_mode)) return; /* Derive custom permissions based on parent and current node */ - switch (parent_info->perm) { + switch (parent_data->perm) { case PERM_INHERIT: case PERM_ANDROID_PACKAGE_CACHE: /* Already inherited above */ break; case PERM_PRE_ROOT: /* Legacy internal layout places users at top level */ - info->perm = PERM_ROOT; + info->data->perm = PERM_ROOT; err = kstrtoul(name->name, 10, &user_num); if (err) - info->userid = 0; + info->data->userid = 0; else - info->userid = user_num; - set_top(info, &info->vfs_inode); + info->data->userid = user_num; + set_top(info, info->data); break; case PERM_ROOT: /* Assume masked off by default. */ if (qstr_case_eq(name, &q_Android)) { /* App-specific directories inside; let anyone traverse */ - info->perm = PERM_ANDROID; - info->under_android = true; - set_top(info, &info->vfs_inode); + info->data->perm = PERM_ANDROID; + info->data->under_android = true; + set_top(info, info->data); } break; case PERM_ANDROID: if (qstr_case_eq(name, &q_data)) { /* App-specific directories inside; let anyone traverse */ - info->perm = PERM_ANDROID_DATA; - set_top(info, &info->vfs_inode); + info->data->perm = PERM_ANDROID_DATA; + set_top(info, info->data); } else if (qstr_case_eq(name, &q_obb)) { /* App-specific directories inside; let anyone traverse */ - info->perm = PERM_ANDROID_OBB; - info->under_obb = true; - set_top(info, &info->vfs_inode); + info->data->perm = PERM_ANDROID_OBB; + info->data->under_obb = true; + set_top(info, info->data); /* Single OBB directory is always shared */ } else if (qstr_case_eq(name, &q_media)) { /* App-specific directories inside; let anyone traverse */ - info->perm = PERM_ANDROID_MEDIA; - set_top(info, &info->vfs_inode); + info->data->perm = PERM_ANDROID_MEDIA; + set_top(info, info->data); } break; case PERM_ANDROID_OBB: case PERM_ANDROID_DATA: case PERM_ANDROID_MEDIA: - info->perm = PERM_ANDROID_PACKAGE; + info->data->perm = PERM_ANDROID_PACKAGE; appid = get_appid(name->name); - if (appid != 0 && !is_excluded(name->name, parent_info->userid)) - info->d_uid = multiuser_get_uid(parent_info->userid, appid); - set_top(info, &info->vfs_inode); + if (appid != 0 && !is_excluded(name->name, parent_data->userid)) + info->data->d_uid = + multiuser_get_uid(parent_data->userid, appid); + set_top(info, info->data); break; case PERM_ANDROID_PACKAGE: if (qstr_case_eq(name, &q_cache)) { - info->perm = PERM_ANDROID_PACKAGE_CACHE; - info->under_cache = true; + info->data->perm = PERM_ANDROID_PACKAGE_CACHE; + info->data->under_cache = true; } break; } @@ -166,7 +168,8 @@ void fixup_lower_ownership(struct dentry *dentry, const char *name) struct inode *delegated_inode = NULL; int error; struct sdcardfs_inode_info *info; - struct sdcardfs_inode_info *info_top; + struct sdcardfs_inode_data *info_d; + struct sdcardfs_inode_data *info_top; perm_t perm; struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb); uid_t uid = sbi->options.fs_low_uid; @@ -174,15 +177,16 @@ void fixup_lower_ownership(struct dentry *dentry, const char *name) struct iattr newattrs; info = SDCARDFS_I(d_inode(dentry)); - perm = info->perm; - if (info->under_obb) { + info_d = info->data; + perm = info_d->perm; + if (info_d->under_obb) { perm = PERM_ANDROID_OBB; - } else if (info->under_cache) { + } else if (info_d->under_cache) { perm = PERM_ANDROID_PACKAGE_CACHE; } else if (perm == PERM_INHERIT) { - info_top = SDCARDFS_I(grab_top(info)); + info_top = top_data_get(info); perm = info_top->perm; - release_top(info); + data_put(info_top); } switch (perm) { @@ -192,7 +196,7 @@ void fixup_lower_ownership(struct dentry *dentry, const char *name) case PERM_ANDROID_MEDIA: case PERM_ANDROID_PACKAGE: case PERM_ANDROID_PACKAGE_CACHE: - uid = multiuser_get_uid(info->userid, uid); + uid = multiuser_get_uid(info_d->userid, uid); break; case PERM_ANDROID_OBB: uid = AID_MEDIA_OBB; @@ -207,24 +211,24 @@ void fixup_lower_ownership(struct dentry *dentry, const char *name) case PERM_ANDROID_DATA: case PERM_ANDROID_MEDIA: if (S_ISDIR(d_inode(dentry)->i_mode)) - gid = multiuser_get_uid(info->userid, AID_MEDIA_RW); + gid = multiuser_get_uid(info_d->userid, AID_MEDIA_RW); else - gid = multiuser_get_uid(info->userid, get_type(name)); + gid = multiuser_get_uid(info_d->userid, get_type(name)); break; case PERM_ANDROID_OBB: gid = AID_MEDIA_OBB; break; case PERM_ANDROID_PACKAGE: - if (uid_is_app(info->d_uid)) - gid = multiuser_get_ext_gid(info->d_uid); + if (uid_is_app(info_d->d_uid)) + gid = multiuser_get_ext_gid(info_d->d_uid); else - gid = multiuser_get_uid(info->userid, AID_MEDIA_RW); + gid = multiuser_get_uid(info_d->userid, AID_MEDIA_RW); break; case PERM_ANDROID_PACKAGE_CACHE: - if (uid_is_app(info->d_uid)) - gid = multiuser_get_ext_cache_gid(info->d_uid); + if (uid_is_app(info_d->d_uid)) + gid = multiuser_get_ext_cache_gid(info_d->d_uid); else - gid = multiuser_get_uid(info->userid, AID_MEDIA_RW); + gid = multiuser_get_uid(info_d->userid, AID_MEDIA_RW); break; case PERM_PRE_ROOT: default: @@ -257,11 +261,13 @@ retry_deleg: sdcardfs_put_lower_path(dentry, &path); } -static int descendant_may_need_fixup(struct sdcardfs_inode_info *info, struct limit_search *limit) +static int descendant_may_need_fixup(struct sdcardfs_inode_data *data, + struct limit_search *limit) { - if (info->perm == PERM_ROOT) - return (limit->flags & BY_USERID)?info->userid == limit->userid:1; - if (info->perm == PERM_PRE_ROOT || info->perm == PERM_ANDROID) + if (data->perm == PERM_ROOT) + return (limit->flags & BY_USERID) ? + data->userid == limit->userid : 1; + if (data->perm == PERM_PRE_ROOT || data->perm == PERM_ANDROID) return 1; return 0; } @@ -292,7 +298,7 @@ static void __fixup_perms_recursive(struct dentry *dentry, struct limit_search * } info = SDCARDFS_I(d_inode(dentry)); - if (needs_fixup(info->perm)) { + if (needs_fixup(info->data->perm)) { list_for_each_entry(child, &dentry->d_subdirs, d_child) { spin_lock_nested(&child->d_lock, depth + 1); if (!(limit->flags & BY_NAME) || qstr_case_eq(&child->d_name, &limit->name)) { @@ -305,7 +311,7 @@ static void __fixup_perms_recursive(struct dentry *dentry, struct limit_search * } spin_unlock(&child->d_lock); } - } else if (descendant_may_need_fixup(info, limit)) { + } else if (descendant_may_need_fixup(info->data, limit)) { list_for_each_entry(child, &dentry->d_subdirs, d_child) { __fixup_perms_recursive(child, limit, depth + 1); } @@ -349,12 +355,12 @@ int need_graft_path(struct dentry *dentry) struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb); struct qstr obb = QSTR_LITERAL("obb"); - if (parent_info->perm == PERM_ANDROID && + if (parent_info->data->perm == PERM_ANDROID && qstr_case_eq(&dentry->d_name, &obb)) { /* /Android/obb is the base obbpath of DERIVED_UNIFIED */ if (!(sbi->options.multiuser == false - && parent_info->userid == 0)) { + && parent_info->data->userid == 0)) { ret = 1; } } @@ -415,11 +421,11 @@ int is_base_obbpath(struct dentry *dentry) spin_lock(&SDCARDFS_D(dentry)->lock); if (sbi->options.multiuser) { - if (parent_info->perm == PERM_PRE_ROOT && + if (parent_info->data->perm == PERM_PRE_ROOT && qstr_case_eq(&dentry->d_name, &q_obb)) { ret = 1; } - } else if (parent_info->perm == PERM_ANDROID && + } else if (parent_info->data->perm == PERM_ANDROID && qstr_case_eq(&dentry->d_name, &q_obb)) { ret = 1; } diff --git a/fs/sdcardfs/inode.c b/fs/sdcardfs/inode.c index 4f09eebd7d95..60fea424835f 100644 --- a/fs/sdcardfs/inode.c +++ b/fs/sdcardfs/inode.c @@ -23,7 +23,8 @@ #include <linux/ratelimit.h> /* Do not directly use this function. Use OVERRIDE_CRED() instead. */ -const struct cred *override_fsids(struct sdcardfs_sb_info *sbi, struct sdcardfs_inode_info *info) +const struct cred *override_fsids(struct sdcardfs_sb_info *sbi, + struct sdcardfs_inode_data *data) { struct cred *cred; const struct cred *old_cred; @@ -33,10 +34,10 @@ const struct cred *override_fsids(struct sdcardfs_sb_info *sbi, struct sdcardfs_ if (!cred) return NULL; - if (info->under_obb) + if (data->under_obb) uid = AID_MEDIA_OBB; else - uid = multiuser_get_uid(info->userid, sbi->options.fs_low_uid); + uid = multiuser_get_uid(data->userid, sbi->options.fs_low_uid); cred->fsuid = make_kuid(&init_user_ns, uid); cred->fsgid = make_kgid(&init_user_ns, sbi->options.fs_low_gid); @@ -96,7 +97,8 @@ static int sdcardfs_create(struct inode *dir, struct dentry *dentry, if (err) goto out; - err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path, SDCARDFS_I(dir)->userid); + err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path, + SDCARDFS_I(dir)->data->userid); if (err) goto out; fsstack_copy_attr_times(dir, sdcardfs_lower_inode(dir)); @@ -267,7 +269,7 @@ static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode struct path lower_path; struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb); const struct cred *saved_cred = NULL; - struct sdcardfs_inode_info *pi = SDCARDFS_I(dir); + struct sdcardfs_inode_data *pd = SDCARDFS_I(dir)->data; int touch_err = 0; struct fs_struct *saved_fs; struct fs_struct *copied_fs; @@ -336,7 +338,7 @@ static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode make_nomedia_in_obb = 1; } - err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path, pi->userid); + err = sdcardfs_interpose(dentry, dir->i_sb, &lower_path, pd->userid); if (err) { unlock_dir(lower_parent_dentry); goto out; @@ -349,12 +351,13 @@ static int sdcardfs_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode fixup_lower_ownership(dentry, dentry->d_name.name); unlock_dir(lower_parent_dentry); if ((!sbi->options.multiuser) && (qstr_case_eq(&dentry->d_name, &q_obb)) - && (pi->perm == PERM_ANDROID) && (pi->userid == 0)) + && (pd->perm == PERM_ANDROID) && (pd->userid == 0)) make_nomedia_in_obb = 1; /* When creating /Android/data and /Android/obb, mark them as .nomedia */ if (make_nomedia_in_obb || - ((pi->perm == PERM_ANDROID) && (qstr_case_eq(&dentry->d_name, &q_data)))) { + ((pd->perm == PERM_ANDROID) + && (qstr_case_eq(&dentry->d_name, &q_data)))) { REVERT_CRED(saved_cred); OVERRIDE_CRED(SDCARDFS_SB(dir->i_sb), saved_cred, SDCARDFS_I(d_inode(dentry))); set_fs_pwd(current->fs, &lower_path); @@ -616,7 +619,7 @@ static int sdcardfs_permission(struct vfsmount *mnt, struct inode *inode, int ma { int err; struct inode tmp; - struct inode *top = grab_top(SDCARDFS_I(inode)); + struct sdcardfs_inode_data *top = top_data_get(SDCARDFS_I(inode)); if (!top) return -EINVAL; @@ -633,10 +636,11 @@ static int sdcardfs_permission(struct vfsmount *mnt, struct inode *inode, int ma * locks must be dealt with to avoid undefined behavior. */ copy_attrs(&tmp, inode); - tmp.i_uid = make_kuid(&init_user_ns, SDCARDFS_I(top)->d_uid); - tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, SDCARDFS_I(top))); - tmp.i_mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(top)); - release_top(SDCARDFS_I(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_mode = (inode->i_mode & S_IFMT) + | get_mode(mnt, SDCARDFS_I(inode), top); + data_put(top); tmp.i_sb = inode->i_sb; if (IS_POSIXACL(inode)) pr_warn("%s: This may be undefined behavior...\n", __func__); @@ -687,11 +691,11 @@ static int sdcardfs_setattr(struct vfsmount *mnt, struct dentry *dentry, struct struct iattr lower_ia; struct dentry *parent; struct inode tmp; - struct inode *top; + struct sdcardfs_inode_data *top; const struct cred *saved_cred = NULL; inode = d_inode(dentry); - top = grab_top(SDCARDFS_I(inode)); + top = top_data_get(SDCARDFS_I(inode)); if (!top) return -EINVAL; @@ -709,11 +713,12 @@ static int sdcardfs_setattr(struct vfsmount *mnt, struct dentry *dentry, struct * */ copy_attrs(&tmp, inode); - tmp.i_uid = make_kuid(&init_user_ns, SDCARDFS_I(top)->d_uid); - tmp.i_gid = make_kgid(&init_user_ns, get_gid(mnt, SDCARDFS_I(top))); - tmp.i_mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(top)); + 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_mode = (inode->i_mode & S_IFMT) + | get_mode(mnt, SDCARDFS_I(inode), top); tmp.i_size = i_size_read(inode); - release_top(SDCARDFS_I(inode)); + data_put(top); tmp.i_sb = inode->i_sb; /* @@ -815,17 +820,17 @@ static int sdcardfs_fillattr(struct vfsmount *mnt, struct inode *inode, struct kstat *stat) { struct sdcardfs_inode_info *info = SDCARDFS_I(inode); - struct inode *top = grab_top(info); + struct sdcardfs_inode_data *top = top_data_get(info); if (!top) return -EINVAL; stat->dev = inode->i_sb->s_dev; stat->ino = inode->i_ino; - stat->mode = (inode->i_mode & S_IFMT) | get_mode(mnt, SDCARDFS_I(top)); + stat->mode = (inode->i_mode & S_IFMT) | get_mode(mnt, info, top); stat->nlink = inode->i_nlink; - stat->uid = make_kuid(&init_user_ns, SDCARDFS_I(top)->d_uid); - stat->gid = make_kgid(&init_user_ns, get_gid(mnt, SDCARDFS_I(top))); + stat->uid = make_kuid(&init_user_ns, top->d_uid); + stat->gid = make_kgid(&init_user_ns, get_gid(mnt, top)); stat->rdev = inode->i_rdev; stat->size = i_size_read(inode); stat->atime = inode->i_atime; @@ -833,7 +838,7 @@ static int sdcardfs_fillattr(struct vfsmount *mnt, stat->ctime = inode->i_ctime; stat->blksize = (1 << inode->i_blkbits); stat->blocks = inode->i_blocks; - release_top(info); + data_put(top); return 0; } diff --git a/fs/sdcardfs/lookup.c b/fs/sdcardfs/lookup.c index 509d5fbcb472..00ae21151f52 100644 --- a/fs/sdcardfs/lookup.c +++ b/fs/sdcardfs/lookup.c @@ -71,7 +71,7 @@ struct inode_data { static int sdcardfs_inode_test(struct inode *inode, void *candidate_data/*void *candidate_lower_inode*/) { struct inode *current_lower_inode = sdcardfs_lower_inode(inode); - userid_t current_userid = SDCARDFS_I(inode)->userid; + userid_t current_userid = SDCARDFS_I(inode)->data->userid; if (current_lower_inode == ((struct inode_data *)candidate_data)->lower_inode && current_userid == ((struct inode_data *)candidate_data)->id) @@ -438,7 +438,8 @@ struct dentry *sdcardfs_lookup(struct inode *dir, struct dentry *dentry, goto out; } - ret = __sdcardfs_lookup(dentry, flags, &lower_parent_path, SDCARDFS_I(dir)->userid); + ret = __sdcardfs_lookup(dentry, flags, &lower_parent_path, + SDCARDFS_I(dir)->data->userid); if (IS_ERR(ret)) goto out; if (ret) diff --git a/fs/sdcardfs/main.c b/fs/sdcardfs/main.c index 953d2156d2e9..3c5b51d49d21 100644 --- a/fs/sdcardfs/main.c +++ b/fs/sdcardfs/main.c @@ -327,13 +327,13 @@ static int sdcardfs_read_super(struct vfsmount *mnt, struct super_block *sb, mutex_lock(&sdcardfs_super_list_lock); if (sb_info->options.multiuser) { setup_derived_state(d_inode(sb->s_root), PERM_PRE_ROOT, - sb_info->options.fs_user_id, AID_ROOT, - false, d_inode(sb->s_root)); + sb_info->options.fs_user_id, AID_ROOT, + false, SDCARDFS_I(d_inode(sb->s_root))->data); snprintf(sb_info->obbpath_s, PATH_MAX, "%s/obb", dev_name); } else { setup_derived_state(d_inode(sb->s_root), PERM_ROOT, - sb_info->options.fs_user_id, AID_ROOT, - false, d_inode(sb->s_root)); + sb_info->options.fs_user_id, AID_ROOT, + false, SDCARDFS_I(d_inode(sb->s_root))->data); snprintf(sb_info->obbpath_s, PATH_MAX, "%s/Android/obb", dev_name); } fixup_tmp_permissions(d_inode(sb->s_root)); diff --git a/fs/sdcardfs/packagelist.c b/fs/sdcardfs/packagelist.c index 89196e31073e..8495474258d5 100644 --- a/fs/sdcardfs/packagelist.c +++ b/fs/sdcardfs/packagelist.c @@ -156,7 +156,7 @@ int check_caller_access_to_name(struct inode *parent_node, const struct qstr *na struct qstr q_android_secure = QSTR_LITERAL("android_secure"); /* Always block security-sensitive files at root */ - if (parent_node && SDCARDFS_I(parent_node)->perm == PERM_ROOT) { + if (parent_node && SDCARDFS_I(parent_node)->data->perm == PERM_ROOT) { if (qstr_case_eq(name, &q_autorun) || qstr_case_eq(name, &q__android_secure) || qstr_case_eq(name, &q_android_secure)) { diff --git a/fs/sdcardfs/sdcardfs.h b/fs/sdcardfs/sdcardfs.h index 2b67b9a8ef9f..31d37d7da4f9 100644 --- a/fs/sdcardfs/sdcardfs.h +++ b/fs/sdcardfs/sdcardfs.h @@ -30,6 +30,7 @@ #include <linux/file.h> #include <linux/fs.h> #include <linux/aio.h> +#include <linux/kref.h> #include <linux/mm.h> #include <linux/mount.h> #include <linux/namei.h> @@ -81,7 +82,8 @@ */ #define fixup_tmp_permissions(x) \ do { \ - (x)->i_uid = make_kuid(&init_user_ns, SDCARDFS_I(x)->d_uid); \ + (x)->i_uid = make_kuid(&init_user_ns, \ + SDCARDFS_I(x)->data->d_uid); \ (x)->i_gid = make_kgid(&init_user_ns, AID_SDCARD_RW); \ (x)->i_mode = ((x)->i_mode & S_IFMT) | 0775;\ } while (0) @@ -97,16 +99,16 @@ */ #define OVERRIDE_CRED(sdcardfs_sbi, saved_cred, info) \ do { \ - saved_cred = override_fsids(sdcardfs_sbi, info); \ - if (!saved_cred) \ - return -ENOMEM; \ + saved_cred = override_fsids(sdcardfs_sbi, info->data); \ + if (!saved_cred) \ + return -ENOMEM; \ } while (0) #define OVERRIDE_CRED_PTR(sdcardfs_sbi, saved_cred, info) \ do { \ - saved_cred = override_fsids(sdcardfs_sbi, info); \ - if (!saved_cred) \ - return ERR_PTR(-ENOMEM); \ + saved_cred = override_fsids(sdcardfs_sbi, info->data); \ + if (!saved_cred) \ + return ERR_PTR(-ENOMEM); \ } while (0) #define REVERT_CRED(saved_cred) revert_fsids(saved_cred) @@ -142,9 +144,11 @@ typedef enum { struct sdcardfs_sb_info; struct sdcardfs_mount_options; struct sdcardfs_inode_info; +struct sdcardfs_inode_data; /* Do not directly use this function. Use OVERRIDE_CRED() instead. */ -const struct cred *override_fsids(struct sdcardfs_sb_info *sbi, struct sdcardfs_inode_info *info); +const struct cred *override_fsids(struct sdcardfs_sb_info *sbi, + struct sdcardfs_inode_data *data); /* Do not directly use this function, use REVERT_CRED() instead. */ void revert_fsids(const struct cred *old_cred); @@ -178,18 +182,26 @@ struct sdcardfs_file_info { const struct vm_operations_struct *lower_vm_ops; }; -/* sdcardfs inode data in memory */ -struct sdcardfs_inode_info { - struct inode *lower_inode; - /* state derived based on current position in hierachy */ +struct sdcardfs_inode_data { + struct kref refcount; + bool abandoned; + perm_t perm; userid_t userid; uid_t d_uid; bool under_android; bool under_cache; bool under_obb; +}; + +/* sdcardfs inode data in memory */ +struct sdcardfs_inode_info { + struct inode *lower_inode; + /* state derived based on current position in hierarchy */ + struct sdcardfs_inode_data *data; + /* top folder for ownership */ - struct inode *top; + struct sdcardfs_inode_data *top_data; struct inode vfs_inode; }; @@ -351,39 +363,56 @@ SDCARDFS_DENT_FUNC(orig_path) static inline bool sbinfo_has_sdcard_magic(struct sdcardfs_sb_info *sbinfo) { - return sbinfo && sbinfo->sb && sbinfo->sb->s_magic == SDCARDFS_SUPER_MAGIC; + return sbinfo && sbinfo->sb + && sbinfo->sb->s_magic == SDCARDFS_SUPER_MAGIC; } -/* grab a refererence if we aren't linking to ourself */ -static inline void set_top(struct sdcardfs_inode_info *info, struct inode *top) +static inline struct sdcardfs_inode_data *data_get( + struct sdcardfs_inode_data *data) { - struct inode *old_top = NULL; - - BUG_ON(IS_ERR_OR_NULL(top)); - if (info->top && info->top != &info->vfs_inode) - old_top = info->top; - if (top != &info->vfs_inode) - igrab(top); - info->top = top; - iput(old_top); + if (data) + kref_get(&data->refcount); + return data; } -static inline struct inode *grab_top(struct sdcardfs_inode_info *info) +static inline struct sdcardfs_inode_data *top_data_get( + struct sdcardfs_inode_info *info) { - struct inode *top = info->top; + return data_get(info->top_data); +} - if (top) - return igrab(top); - else - return NULL; +extern void data_release(struct kref *ref); + +static inline void data_put(struct sdcardfs_inode_data *data) +{ + kref_put(&data->refcount, data_release); +} + +static inline void release_own_data(struct sdcardfs_inode_info *info) +{ + /* + * This happens exactly once per inode. At this point, the inode that + * originally held this data is about to be freed, and all references + * to it are held as a top value, and will likely be released soon. + */ + info->data->abandoned = true; + data_put(info->data); } -static inline void release_top(struct sdcardfs_inode_info *info) +static inline void set_top(struct sdcardfs_inode_info *info, + struct sdcardfs_inode_data *top) { - iput(info->top); + struct sdcardfs_inode_data *old_top = info->top_data; + + if (top) + data_get(top); + info->top_data = top; + if (old_top) + data_put(old_top); } -static inline int get_gid(struct vfsmount *mnt, struct sdcardfs_inode_info *info) +static inline int get_gid(struct vfsmount *mnt, + struct sdcardfs_inode_data *data) { struct sdcardfs_vfsmount_options *opts = mnt->data; @@ -396,10 +425,12 @@ static inline int get_gid(struct vfsmount *mnt, struct sdcardfs_inode_info *info */ return AID_SDCARD_RW; else - return multiuser_get_uid(info->userid, opts->gid); + return multiuser_get_uid(data->userid, opts->gid); } -static inline int get_mode(struct vfsmount *mnt, struct sdcardfs_inode_info *info) +static inline int get_mode(struct vfsmount *mnt, + struct sdcardfs_inode_info *info, + struct sdcardfs_inode_data *data) { int owner_mode; int filtered_mode; @@ -407,12 +438,12 @@ static inline int get_mode(struct vfsmount *mnt, struct sdcardfs_inode_info *inf int visible_mode = 0775 & ~opts->mask; - if (info->perm == PERM_PRE_ROOT) { + if (data->perm == PERM_PRE_ROOT) { /* Top of multi-user view should always be visible to ensure * secondary users can traverse inside. */ visible_mode = 0711; - } else if (info->under_android) { + } else if (data->under_android) { /* Block "other" access to Android directories, since only apps * belonging to a specific user should be in there; we still * leave +x open for the default view. @@ -481,8 +512,9 @@ struct limit_search { userid_t userid; }; -extern void setup_derived_state(struct inode *inode, perm_t perm, userid_t userid, - uid_t uid, bool under_android, struct inode *top); +extern void setup_derived_state(struct inode *inode, perm_t perm, + userid_t userid, uid_t uid, bool under_android, + struct sdcardfs_inode_data *top); extern void get_derived_permission(struct dentry *parent, struct dentry *dentry); extern void get_derived_permission_new(struct dentry *parent, struct dentry *dentry, const struct qstr *name); extern void fixup_perms_recursive(struct dentry *dentry, struct limit_search *limit); @@ -601,7 +633,7 @@ static inline void sdcardfs_copy_and_fix_attrs(struct inode *dest, const struct { dest->i_mode = (src->i_mode & S_IFMT) | S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH; /* 0775 */ - dest->i_uid = make_kuid(&init_user_ns, SDCARDFS_I(dest)->d_uid); + dest->i_uid = make_kuid(&init_user_ns, SDCARDFS_I(dest)->data->d_uid); dest->i_gid = make_kgid(&init_user_ns, AID_SDCARD_RW); dest->i_rdev = src->i_rdev; dest->i_atime = src->i_atime; diff --git a/fs/sdcardfs/super.c b/fs/sdcardfs/super.c index 8a9c9c7adca2..7f4539b4b249 100644 --- a/fs/sdcardfs/super.c +++ b/fs/sdcardfs/super.c @@ -26,6 +26,23 @@ */ static struct kmem_cache *sdcardfs_inode_cachep; +/* + * To support the top references, we must track some data separately. + * An sdcardfs_inode_info always has a reference to its data, and once set up, + * also has a reference to its top. The top may be itself, in which case it + * holds two references to its data. When top is changed, it takes a ref to the + * new data and then drops the ref to the old data. + */ +static struct kmem_cache *sdcardfs_inode_data_cachep; + +void data_release(struct kref *ref) +{ + struct sdcardfs_inode_data *data = + container_of(ref, struct sdcardfs_inode_data, refcount); + + kmem_cache_free(sdcardfs_inode_data_cachep, data); +} + /* final actions when unmounting a file system */ static void sdcardfs_put_super(struct super_block *sb) { @@ -166,6 +183,7 @@ static void sdcardfs_evict_inode(struct inode *inode) struct inode *lower_inode; truncate_inode_pages(&inode->i_data, 0); + set_top(SDCARDFS_I(inode), NULL); clear_inode(inode); /* * Decrement a reference to a lower_inode, which was incremented @@ -173,13 +191,13 @@ static void sdcardfs_evict_inode(struct inode *inode) */ lower_inode = sdcardfs_lower_inode(inode); sdcardfs_set_lower_inode(inode, NULL); - set_top(SDCARDFS_I(inode), inode); iput(lower_inode); } static struct inode *sdcardfs_alloc_inode(struct super_block *sb) { struct sdcardfs_inode_info *i; + struct sdcardfs_inode_data *d; i = kmem_cache_alloc(sdcardfs_inode_cachep, GFP_KERNEL); if (!i) @@ -188,6 +206,16 @@ static struct inode *sdcardfs_alloc_inode(struct super_block *sb) /* memset everything up to the inode to 0 */ memset(i, 0, offsetof(struct sdcardfs_inode_info, vfs_inode)); + d = kmem_cache_alloc(sdcardfs_inode_data_cachep, + GFP_KERNEL | __GFP_ZERO); + if (!d) { + kmem_cache_free(sdcardfs_inode_cachep, i); + return NULL; + } + + i->data = d; + kref_init(&d->refcount); + i->vfs_inode.i_version = 1; return &i->vfs_inode; } @@ -196,6 +224,7 @@ static void i_callback(struct rcu_head *head) { struct inode *inode = container_of(head, struct inode, i_rcu); + release_own_data(SDCARDFS_I(inode)); kmem_cache_free(sdcardfs_inode_cachep, SDCARDFS_I(inode)); } @@ -214,20 +243,30 @@ static void init_once(void *obj) int sdcardfs_init_inode_cache(void) { - int err = 0; - sdcardfs_inode_cachep = kmem_cache_create("sdcardfs_inode_cache", sizeof(struct sdcardfs_inode_info), 0, SLAB_RECLAIM_ACCOUNT, init_once); + if (!sdcardfs_inode_cachep) - err = -ENOMEM; - return err; + return -ENOMEM; + + sdcardfs_inode_data_cachep = + kmem_cache_create("sdcardfs_inode_data_cache", + sizeof(struct sdcardfs_inode_data), 0, + SLAB_RECLAIM_ACCOUNT, NULL); + if (!sdcardfs_inode_data_cachep) { + kmem_cache_destroy(sdcardfs_inode_cachep); + return -ENOMEM; + } + + return 0; } /* sdcardfs inode cache destructor */ void sdcardfs_destroy_inode_cache(void) { + kmem_cache_destroy(sdcardfs_inode_data_cachep); kmem_cache_destroy(sdcardfs_inode_cachep); } |