diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/posix_acl.c | 30 | ||||
| -rw-r--r-- | fs/xattr.c | 7 | ||||
| -rw-r--r-- | fs/xattr_acl.c | 90 |
3 files changed, 107 insertions, 20 deletions
diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 5e325a42..8bd2135 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -78,7 +78,8 @@ posix_acl_valid(const struct posix_acl *acl) { const struct posix_acl_entry *pa, *pe; int state = ACL_USER_OBJ; - unsigned int id = 0; /* keep gcc happy */ + kuid_t prev_uid = INVALID_UID; + kgid_t prev_gid = INVALID_GID; int needs_mask = 0; FOREACH_ACL_ENTRY(pa, acl, pe) { @@ -87,7 +88,6 @@ posix_acl_valid(const struct posix_acl *acl) switch (pa->e_tag) { case ACL_USER_OBJ: if (state == ACL_USER_OBJ) { - id = 0; state = ACL_USER; break; } @@ -96,16 +96,17 @@ posix_acl_valid(const struct posix_acl *acl) case ACL_USER: if (state != ACL_USER) return -EINVAL; - if (pa->e_id == ACL_UNDEFINED_ID || - pa->e_id < id) + if (!uid_valid(pa->e_uid)) return -EINVAL; - id = pa->e_id + 1; + if (uid_valid(prev_uid) && + uid_lte(pa->e_uid, prev_uid)) + return -EINVAL; + prev_uid = pa->e_uid; needs_mask = 1; break; case ACL_GROUP_OBJ: if (state == ACL_USER) { - id = 0; state = ACL_GROUP; break; } @@ -114,10 +115,12 @@ posix_acl_valid(const struct posix_acl *acl) case ACL_GROUP: if (state != ACL_GROUP) return -EINVAL; - if (pa->e_id == ACL_UNDEFINED_ID || - pa->e_id < id) + if (!gid_valid(pa->e_gid)) + return -EINVAL; + if (gid_valid(prev_gid) && + gid_lte(pa->e_gid, prev_gid)) return -EINVAL; - id = pa->e_id + 1; + prev_gid = pa->e_gid; needs_mask = 1; break; @@ -195,15 +198,12 @@ posix_acl_from_mode(umode_t mode, gfp_t flags) return ERR_PTR(-ENOMEM); acl->a_entries[0].e_tag = ACL_USER_OBJ; - acl->a_entries[0].e_id = ACL_UNDEFINED_ID; acl->a_entries[0].e_perm = (mode & S_IRWXU) >> 6; acl->a_entries[1].e_tag = ACL_GROUP_OBJ; - acl->a_entries[1].e_id = ACL_UNDEFINED_ID; acl->a_entries[1].e_perm = (mode & S_IRWXG) >> 3; acl->a_entries[2].e_tag = ACL_OTHER; - acl->a_entries[2].e_id = ACL_UNDEFINED_ID; acl->a_entries[2].e_perm = (mode & S_IRWXO); return acl; } @@ -224,11 +224,11 @@ posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want) switch(pa->e_tag) { case ACL_USER_OBJ: /* (May have been checked already) */ - if (inode->i_uid == current_fsuid()) + if (uid_eq(inode->i_uid, current_fsuid())) goto check_perm; break; case ACL_USER: - if (pa->e_id == current_fsuid()) + if (uid_eq(pa->e_uid, current_fsuid())) goto mask; break; case ACL_GROUP_OBJ: @@ -239,7 +239,7 @@ posix_acl_permission(struct inode *inode, const struct posix_acl *acl, int want) } break; case ACL_GROUP: - if (in_group_p(pa->e_id)) { + if (in_group_p(pa->e_gid)) { found = 1; if ((pa->e_perm & want) == want) goto mask; @@ -20,6 +20,7 @@ #include <linux/fsnotify.h> #include <linux/audit.h> #include <linux/vmalloc.h> +#include <linux/posix_acl_xattr.h> #include <asm/uaccess.h> @@ -347,6 +348,9 @@ setxattr(struct dentry *d, const char __user *name, const void __user *value, error = -EFAULT; goto out; } + if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) || + (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0)) + posix_acl_fix_xattr_from_user(kvalue, size); } error = vfs_setxattr(d, kname, kvalue, size, flags); @@ -450,6 +454,9 @@ getxattr(struct dentry *d, const char __user *name, void __user *value, error = vfs_getxattr(d, kname, kvalue, size); if (error > 0) { + if ((strcmp(kname, XATTR_NAME_POSIX_ACL_ACCESS) == 0) || + (strcmp(kname, XATTR_NAME_POSIX_ACL_DEFAULT) == 0)) + posix_acl_fix_xattr_to_user(kvalue, size); if (size && copy_to_user(value, kvalue, error)) error = -EFAULT; } else if (error == -ERANGE && size >= XATTR_SIZE_MAX) { diff --git a/fs/xattr_acl.c b/fs/xattr_acl.c index 69d06b0..bf472ca 100644 --- a/fs/xattr_acl.c +++ b/fs/xattr_acl.c @@ -9,7 +9,65 @@ #include <linux/fs.h> #include <linux/posix_acl_xattr.h> #include <linux/gfp.h> +#include <linux/user_namespace.h> +/* + * Fix up the uids and gids in posix acl extended attributes in place. + */ +static void posix_acl_fix_xattr_userns( + struct user_namespace *to, struct user_namespace *from, + void *value, size_t size) +{ + posix_acl_xattr_header *header = (posix_acl_xattr_header *)value; + posix_acl_xattr_entry *entry = (posix_acl_xattr_entry *)(header+1), *end; + int count; + kuid_t uid; + kgid_t gid; + + if (!value) + return; + if (size < sizeof(posix_acl_xattr_header)) + return; + if (header->a_version != cpu_to_le32(POSIX_ACL_XATTR_VERSION)) + return; + + count = posix_acl_xattr_count(size); + if (count < 0) + return; + if (count == 0) + return; + + for (end = entry + count; entry != end; entry++) { + switch(le16_to_cpu(entry->e_tag)) { + case ACL_USER: + uid = make_kuid(from, le32_to_cpu(entry->e_id)); + entry->e_id = cpu_to_le32(from_kuid(to, uid)); + break; + case ACL_GROUP: + gid = make_kgid(from, le32_to_cpu(entry->e_id)); + entry->e_id = cpu_to_le32(from_kuid(to, uid)); + break; + default: + break; + } + } +} + +void posix_acl_fix_xattr_from_user(void *value, size_t size) +{ + struct user_namespace *user_ns = current_user_ns(); + if (user_ns == &init_user_ns) + return; + posix_acl_fix_xattr_userns(&init_user_ns, user_ns, value, size); +} + +void posix_acl_fix_xattr_to_user(void *value, size_t size) +{ + struct user_namespace *user_ns = current_user_ns(); + if (user_ns == &init_user_ns) + return; + posix_acl_fix_xattr_userns(user_ns, &init_user_ns, value, size); +} /* * Convert from extended attribute to in-memory representation. @@ -50,12 +108,21 @@ posix_acl_from_xattr(const void *value, size_t size) case ACL_GROUP_OBJ: case ACL_MASK: case ACL_OTHER: - acl_e->e_id = ACL_UNDEFINED_ID; break; case ACL_USER: + acl_e->e_uid = + make_kuid(&init_user_ns, + le32_to_cpu(entry->e_id)); + if (!uid_valid(acl_e->e_uid)) + goto fail; + break; case ACL_GROUP: - acl_e->e_id = le32_to_cpu(entry->e_id); + acl_e->e_gid = + make_kgid(&init_user_ns, + le32_to_cpu(entry->e_id)); + if (!gid_valid(acl_e->e_gid)) + goto fail; break; default: @@ -89,9 +156,22 @@ posix_acl_to_xattr(const struct posix_acl *acl, void *buffer, size_t size) ext_acl->a_version = cpu_to_le32(POSIX_ACL_XATTR_VERSION); for (n=0; n < acl->a_count; n++, ext_entry++) { - ext_entry->e_tag = cpu_to_le16(acl->a_entries[n].e_tag); - ext_entry->e_perm = cpu_to_le16(acl->a_entries[n].e_perm); - ext_entry->e_id = cpu_to_le32(acl->a_entries[n].e_id); + const struct posix_acl_entry *acl_e = &acl->a_entries[n]; + ext_entry->e_tag = cpu_to_le16(acl_e->e_tag); + ext_entry->e_perm = cpu_to_le16(acl_e->e_perm); + switch(acl_e->e_tag) { + case ACL_USER: + ext_entry->e_id = + cpu_to_le32(from_kuid(&init_user_ns, acl_e->e_uid)); + break; + case ACL_GROUP: + ext_entry->e_id = + cpu_to_le32(from_kgid(&init_user_ns, acl_e->e_gid)); + break; + default: + ext_entry->e_id = cpu_to_le32(ACL_UNDEFINED_ID); + break; + } } return real_size; } |
