diff options
Diffstat (limited to 'fs/gfs2/acl.c')
-rw-r--r-- | fs/gfs2/acl.c | 357 |
1 files changed, 209 insertions, 148 deletions
diff --git a/fs/gfs2/acl.c b/fs/gfs2/acl.c index 3fc4e3ac7d84..3eb1ea846173 100644 --- a/fs/gfs2/acl.c +++ b/fs/gfs2/acl.c @@ -12,6 +12,7 @@ #include <linux/spinlock.h> #include <linux/completion.h> #include <linux/buffer_head.h> +#include <linux/xattr.h> #include <linux/posix_acl.h> #include <linux/posix_acl_xattr.h> #include <linux/gfs2_ondisk.h> @@ -26,108 +27,44 @@ #include "trans.h" #include "util.h" -#define ACL_ACCESS 1 -#define ACL_DEFAULT 0 - -int gfs2_acl_validate_set(struct gfs2_inode *ip, int access, - struct gfs2_ea_request *er, int *remove, mode_t *mode) +static const char *gfs2_acl_name(int type) { - struct posix_acl *acl; - int error; - - error = gfs2_acl_validate_remove(ip, access); - if (error) - return error; - - if (!er->er_data) - return -EINVAL; - - acl = posix_acl_from_xattr(er->er_data, er->er_data_len); - if (IS_ERR(acl)) - return PTR_ERR(acl); - if (!acl) { - *remove = 1; - return 0; - } - - error = posix_acl_valid(acl); - if (error) - goto out; - - if (access) { - error = posix_acl_equiv_mode(acl, mode); - if (!error) - *remove = 1; - else if (error > 0) - error = 0; + switch (type) { + case ACL_TYPE_ACCESS: + return GFS2_POSIX_ACL_ACCESS; + case ACL_TYPE_DEFAULT: + return GFS2_POSIX_ACL_DEFAULT; } - -out: - posix_acl_release(acl); - return error; -} - -int gfs2_acl_validate_remove(struct gfs2_inode *ip, int access) -{ - if (!GFS2_SB(&ip->i_inode)->sd_args.ar_posix_acl) - return -EOPNOTSUPP; - if (!is_owner_or_cap(&ip->i_inode)) - return -EPERM; - if (S_ISLNK(ip->i_inode.i_mode)) - return -EOPNOTSUPP; - if (!access && !S_ISDIR(ip->i_inode.i_mode)) - return -EACCES; - - return 0; + return NULL; } -static int acl_get(struct gfs2_inode *ip, const char *name, - struct posix_acl **acl, struct gfs2_ea_location *el, - char **datap, unsigned int *lenp) +static struct posix_acl *gfs2_acl_get(struct gfs2_inode *ip, int type) { + struct posix_acl *acl; + const char *name; char *data; - unsigned int len; - int error; - - el->el_bh = NULL; + int len; if (!ip->i_eattr) - return 0; - - error = gfs2_ea_find(ip, GFS2_EATYPE_SYS, name, el); - if (error) - return error; - if (!el->el_ea) - return 0; - if (!GFS2_EA_DATA_LEN(el->el_ea)) - goto out; + return NULL; - len = GFS2_EA_DATA_LEN(el->el_ea); - data = kmalloc(len, GFP_NOFS); - error = -ENOMEM; - if (!data) - goto out; + acl = get_cached_acl(&ip->i_inode, type); + if (acl != ACL_NOT_CACHED) + return acl; - error = gfs2_ea_get_copy(ip, el, data, len); - if (error < 0) - goto out_kfree; - error = 0; + name = gfs2_acl_name(type); + if (name == NULL) + return ERR_PTR(-EINVAL); - if (acl) { - *acl = posix_acl_from_xattr(data, len); - if (IS_ERR(*acl)) - error = PTR_ERR(*acl); - } + len = gfs2_xattr_acl_get(ip, name, &data); + if (len < 0) + return ERR_PTR(len); + if (len == 0) + return NULL; -out_kfree: - if (error || !datap) { - kfree(data); - } else { - *datap = data; - *lenp = len; - } -out: - return error; + acl = posix_acl_from_xattr(data, len); + kfree(data); + return acl; } /** @@ -140,14 +77,12 @@ out: int gfs2_check_acl(struct inode *inode, int mask) { - struct gfs2_ea_location el; - struct posix_acl *acl = NULL; + struct posix_acl *acl; int error; - error = acl_get(GFS2_I(inode), GFS2_POSIX_ACL_ACCESS, &acl, &el, NULL, NULL); - brelse(el.el_bh); - if (error) - return error; + acl = gfs2_acl_get(GFS2_I(inode), ACL_TYPE_ACCESS); + if (IS_ERR(acl)) + return PTR_ERR(acl); if (acl) { error = posix_acl_permission(inode, acl, mask); @@ -158,57 +93,75 @@ int gfs2_check_acl(struct inode *inode, int mask) return -EAGAIN; } -static int munge_mode(struct gfs2_inode *ip, mode_t mode) +static int gfs2_set_mode(struct inode *inode, mode_t mode) { - struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); - struct buffer_head *dibh; - int error; + int error = 0; - error = gfs2_trans_begin(sdp, RES_DINODE, 0); - if (error) - return error; + if (mode != inode->i_mode) { + struct iattr iattr; - error = gfs2_meta_inode_buffer(ip, &dibh); - if (!error) { - gfs2_assert_withdraw(sdp, - (ip->i_inode.i_mode & S_IFMT) == (mode & S_IFMT)); - ip->i_inode.i_mode = mode; - gfs2_trans_add_bh(ip->i_gl, dibh, 1); - gfs2_dinode_out(ip, dibh->b_data); - brelse(dibh); + iattr.ia_valid = ATTR_MODE; + iattr.ia_mode = mode; + + error = gfs2_setattr_simple(GFS2_I(inode), &iattr); } - gfs2_trans_end(sdp); + return error; +} + +static int gfs2_acl_set(struct inode *inode, int type, struct posix_acl *acl) +{ + int error; + int len; + char *data; + const char *name = gfs2_acl_name(type); - return 0; + BUG_ON(name == NULL); + len = posix_acl_to_xattr(acl, NULL, 0); + if (len == 0) + return 0; + data = kmalloc(len, GFP_NOFS); + if (data == NULL) + return -ENOMEM; + error = posix_acl_to_xattr(acl, data, len); + if (error < 0) + goto out; + error = gfs2_xattr_set(inode, GFS2_EATYPE_SYS, name, data, len, 0); + if (!error) + set_cached_acl(inode, type, acl); +out: + kfree(data); + return error; } -int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip) +int gfs2_acl_create(struct gfs2_inode *dip, struct inode *inode) { - struct gfs2_ea_location el; struct gfs2_sbd *sdp = GFS2_SB(&dip->i_inode); - struct posix_acl *acl = NULL, *clone; - mode_t mode = ip->i_inode.i_mode; - char *data = NULL; - unsigned int len; - int error; + struct posix_acl *acl, *clone; + mode_t mode = inode->i_mode; + int error = 0; if (!sdp->sd_args.ar_posix_acl) return 0; - if (S_ISLNK(ip->i_inode.i_mode)) + if (S_ISLNK(inode->i_mode)) return 0; - error = acl_get(dip, GFS2_POSIX_ACL_DEFAULT, &acl, &el, &data, &len); - brelse(el.el_bh); - if (error) - return error; + acl = gfs2_acl_get(dip, ACL_TYPE_DEFAULT); + if (IS_ERR(acl)) + return PTR_ERR(acl); if (!acl) { mode &= ~current_umask(); - if (mode != ip->i_inode.i_mode) - error = munge_mode(ip, mode); + if (mode != inode->i_mode) + error = gfs2_set_mode(inode, mode); return error; } + if (S_ISDIR(inode->i_mode)) { + error = gfs2_acl_set(inode, ACL_TYPE_DEFAULT, acl); + if (error) + goto out; + } + clone = posix_acl_clone(acl, GFP_NOFS); error = -ENOMEM; if (!clone) @@ -216,43 +169,32 @@ int gfs2_acl_create(struct gfs2_inode *dip, struct gfs2_inode *ip) posix_acl_release(acl); acl = clone; - if (S_ISDIR(ip->i_inode.i_mode)) { - error = gfs2_xattr_set(&ip->i_inode, GFS2_EATYPE_SYS, - GFS2_POSIX_ACL_DEFAULT, data, len, 0); - if (error) - goto out; - } - error = posix_acl_create_masq(acl, &mode); if (error < 0) goto out; if (error == 0) goto munge; - posix_acl_to_xattr(acl, data, len); - error = gfs2_xattr_set(&ip->i_inode, GFS2_EATYPE_SYS, - GFS2_POSIX_ACL_ACCESS, data, len, 0); + error = gfs2_acl_set(inode, ACL_TYPE_ACCESS, acl); if (error) goto out; munge: - error = munge_mode(ip, mode); + error = gfs2_set_mode(inode, mode); out: posix_acl_release(acl); - kfree(data); return error; } int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr) { - struct posix_acl *acl = NULL, *clone; - struct gfs2_ea_location el; + struct posix_acl *acl, *clone; char *data; unsigned int len; int error; - error = acl_get(ip, GFS2_POSIX_ACL_ACCESS, &acl, &el, &data, &len); - if (error) - goto out_brelse; + acl = gfs2_acl_get(ip, ACL_TYPE_ACCESS); + if (IS_ERR(acl)) + return PTR_ERR(acl); if (!acl) return gfs2_setattr_simple(ip, attr); @@ -265,15 +207,134 @@ int gfs2_acl_chmod(struct gfs2_inode *ip, struct iattr *attr) error = posix_acl_chmod_masq(acl, attr->ia_mode); if (!error) { + len = posix_acl_to_xattr(acl, NULL, 0); + data = kmalloc(len, GFP_NOFS); + error = -ENOMEM; + if (data == NULL) + goto out; posix_acl_to_xattr(acl, data, len); - error = gfs2_ea_acl_chmod(ip, &el, attr, data); + error = gfs2_xattr_acl_chmod(ip, attr, data); + kfree(data); + set_cached_acl(&ip->i_inode, ACL_TYPE_ACCESS, acl); } out: posix_acl_release(acl); - kfree(data); -out_brelse: - brelse(el.el_bh); return error; } +static int gfs2_acl_type(const char *name) +{ + if (strcmp(name, GFS2_POSIX_ACL_ACCESS) == 0) + return ACL_TYPE_ACCESS; + if (strcmp(name, GFS2_POSIX_ACL_DEFAULT) == 0) + return ACL_TYPE_DEFAULT; + return -EINVAL; +} + +static int gfs2_xattr_system_get(struct inode *inode, const char *name, + void *buffer, size_t size) +{ + struct posix_acl *acl; + int type; + int error; + + type = gfs2_acl_type(name); + if (type < 0) + return type; + + acl = gfs2_acl_get(GFS2_I(inode), type); + if (IS_ERR(acl)) + return PTR_ERR(acl); + if (acl == NULL) + return -ENODATA; + + error = posix_acl_to_xattr(acl, buffer, size); + posix_acl_release(acl); + + return error; +} + +static int gfs2_xattr_system_set(struct inode *inode, const char *name, + const void *value, size_t size, int flags) +{ + struct gfs2_sbd *sdp = GFS2_SB(inode); + struct posix_acl *acl = NULL; + int error = 0, type; + + if (!sdp->sd_args.ar_posix_acl) + return -EOPNOTSUPP; + + type = gfs2_acl_type(name); + if (type < 0) + return type; + if (flags & XATTR_CREATE) + return -EINVAL; + if (type == ACL_TYPE_DEFAULT && !S_ISDIR(inode->i_mode)) + return value ? -EACCES : 0; + if ((current_fsuid() != inode->i_uid) && !capable(CAP_FOWNER)) + return -EPERM; + if (S_ISLNK(inode->i_mode)) + return -EOPNOTSUPP; + + if (!value) + goto set_acl; + + acl = posix_acl_from_xattr(value, size); + if (!acl) { + /* + * acl_set_file(3) may request that we set default ACLs with + * zero length -- defend (gracefully) against that here. + */ + goto out; + } + if (IS_ERR(acl)) { + error = PTR_ERR(acl); + goto out; + } + + error = posix_acl_valid(acl); + if (error) + goto out_release; + + error = -EINVAL; + if (acl->a_count > GFS2_ACL_MAX_ENTRIES) + goto out_release; + + if (type == ACL_TYPE_ACCESS) { + mode_t mode = inode->i_mode; + error = posix_acl_equiv_mode(acl, &mode); + + if (error <= 0) { + posix_acl_release(acl); + acl = NULL; + + if (error < 0) + return error; + } + + error = gfs2_set_mode(inode, mode); + if (error) + goto out_release; + } + +set_acl: + error = gfs2_xattr_set(inode, GFS2_EATYPE_SYS, name, value, size, 0); + if (!error) { + if (acl) + set_cached_acl(inode, type, acl); + else + forget_cached_acl(inode, type); + } +out_release: + posix_acl_release(acl); +out: + return error; +} + +struct xattr_handler gfs2_xattr_system_handler = { + .prefix = XATTR_SYSTEM_PREFIX, + .get = gfs2_xattr_system_get, + .set = gfs2_xattr_system_set, +}; + |