diff --git a/fs/internal.h b/fs/internal.h index aa5f240496d96..e377eb7bbe7f2 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -234,4 +234,24 @@ int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, struct xattr_ctx *ctx); int may_write_xattr(struct user_namespace *mnt_userns, struct inode *inode); +#ifdef CONFIG_FS_POSIX_ACL +int do_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *acl_name, const void *kvalue, size_t size); +ssize_t do_get_acl(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *acl_name, void *kvalue, size_t size); +#else +static inline int do_set_acl(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *acl_name, + const void *kvalue, size_t size) +{ + return -EOPNOTSUPP; +} +static inline ssize_t do_get_acl(struct user_namespace *mnt_userns, + struct dentry *dentry, const char *acl_name, + void *kvalue, size_t size) +{ + return -EOPNOTSUPP; +} +#endif + ssize_t __kernel_write_iter(struct file *file, struct iov_iter *from, loff_t *pos); diff --git a/fs/posix_acl.c b/fs/posix_acl.c index 3a141082b24c0..14b87653b797f 100644 --- a/fs/posix_acl.c +++ b/fs/posix_acl.c @@ -1544,3 +1544,40 @@ int vfs_remove_acl(struct user_namespace *mnt_userns, struct dentry *dentry, return error; } EXPORT_SYMBOL_GPL(vfs_remove_acl); + +int do_set_acl(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *acl_name, const void *kvalue, size_t size) +{ + int error; + struct posix_acl *acl = NULL; + + if (size) { + /* + * Note that posix_acl_from_xattr() uses GFP_NOFS when it + * probably doesn't need to here. + */ + acl = posix_acl_from_xattr(current_user_ns(), kvalue, size); + if (IS_ERR(acl)) + return PTR_ERR(acl); + } + + error = vfs_set_acl(mnt_userns, dentry, acl_name, acl); + posix_acl_release(acl); + return error; +} + +ssize_t do_get_acl(struct user_namespace *mnt_userns, struct dentry *dentry, + const char *acl_name, void *kvalue, size_t size) +{ + ssize_t error; + struct posix_acl *acl; + + acl = vfs_get_acl(mnt_userns, dentry, acl_name); + if (IS_ERR(acl)) + return PTR_ERR(acl); + + error = vfs_posix_acl_to_xattr(mnt_userns, d_inode(dentry), + acl, kvalue, size); + posix_acl_release(acl); + return error; +} diff --git a/fs/xattr.c b/fs/xattr.c index 9ed9eea4d1b96..77db5aa26d134 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -189,6 +189,9 @@ __vfs_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, { const struct xattr_handler *handler; + if (is_posix_acl_xattr(name)) + return -EOPNOTSUPP; + handler = xattr_resolve_name(inode, &name); if (IS_ERR(handler)) return PTR_ERR(handler); @@ -410,6 +413,9 @@ __vfs_getxattr(struct dentry *dentry, struct inode *inode, const char *name, { const struct xattr_handler *handler; + if (is_posix_acl_xattr(name)) + return -EOPNOTSUPP; + handler = xattr_resolve_name(inode, &name); if (IS_ERR(handler)) return PTR_ERR(handler); @@ -482,6 +488,9 @@ __vfs_removexattr(struct user_namespace *mnt_userns, struct dentry *dentry, struct inode *inode = d_inode(dentry); const struct xattr_handler *handler; + if (is_posix_acl_xattr(name)) + return -EOPNOTSUPP; + handler = xattr_resolve_name(inode, &name); if (IS_ERR(handler)) return PTR_ERR(handler); @@ -591,17 +600,13 @@ int setxattr_copy(const char __user *name, struct xattr_ctx *ctx) return error; } -static void setxattr_convert(struct user_namespace *mnt_userns, - struct dentry *d, struct xattr_ctx *ctx) -{ - if (ctx->size && is_posix_acl_xattr(ctx->kname->name)) - posix_acl_fix_xattr_from_user(ctx->kvalue, ctx->size); -} - int do_setxattr(struct user_namespace *mnt_userns, struct dentry *dentry, struct xattr_ctx *ctx) { - setxattr_convert(mnt_userns, dentry, ctx); + if (is_posix_acl_xattr(ctx->kname->name)) + return do_set_acl(mnt_userns, dentry, ctx->kname->name, + ctx->kvalue, ctx->size); + return vfs_setxattr(mnt_userns, dentry, ctx->kname->name, ctx->kvalue, ctx->size, ctx->flags); } @@ -708,10 +713,11 @@ do_getxattr(struct user_namespace *mnt_userns, struct dentry *d, return -ENOMEM; } - error = vfs_getxattr(mnt_userns, d, kname, ctx->kvalue, ctx->size); + if (is_posix_acl_xattr(ctx->kname->name)) + error = do_get_acl(mnt_userns, d, kname, ctx->kvalue, ctx->size); + else + error = vfs_getxattr(mnt_userns, d, kname, ctx->kvalue, ctx->size); if (error > 0) { - if (is_posix_acl_xattr(kname)) - posix_acl_fix_xattr_to_user(ctx->kvalue, error); if (ctx->size && copy_to_user(ctx->value, ctx->kvalue, error)) error = -EFAULT; } else if (error == -ERANGE && ctx->size >= XATTR_SIZE_MAX) { @@ -886,6 +892,9 @@ removexattr(struct user_namespace *mnt_userns, struct dentry *d, if (error < 0) return error; + if (is_posix_acl_xattr(kname)) + return vfs_remove_acl(mnt_userns, d, kname); + return vfs_removexattr(mnt_userns, d, kname); } diff --git a/include/linux/posix_acl_xattr.h b/include/linux/posix_acl_xattr.h index bf30296389d77..c5d5fbc348dc1 100644 --- a/include/linux/posix_acl_xattr.h +++ b/include/linux/posix_acl_xattr.h @@ -33,6 +33,8 @@ posix_acl_xattr_count(size_t size) } #ifdef CONFIG_FS_POSIX_ACL +struct posix_acl *posix_acl_from_xattr(struct user_namespace *user_ns, + const void *value, size_t size); void posix_acl_fix_xattr_from_user(void *value, size_t size); void posix_acl_fix_xattr_to_user(void *value, size_t size); void posix_acl_getxattr_idmapped_mnt(struct user_namespace *mnt_userns, @@ -42,6 +44,12 @@ ssize_t vfs_posix_acl_to_xattr(struct user_namespace *mnt_userns, struct inode *inode, const struct posix_acl *acl, void *buffer, size_t size); #else +static inline struct posix_acl * +posix_acl_from_xattr(struct user_namespace *user_ns, const void *value, + size_t size) +{ + return ERR_PTR(-EOPNOTSUPP); +} static inline void posix_acl_fix_xattr_from_user(void *value, size_t size) { } @@ -63,8 +71,6 @@ static inline ssize_t vfs_posix_acl_to_xattr(struct user_namespace *mnt_userns, } #endif -struct posix_acl *posix_acl_from_xattr(struct user_namespace *user_ns, - const void *value, size_t size); int posix_acl_to_xattr(struct user_namespace *user_ns, const struct posix_acl *acl, void *buffer, size_t size); struct posix_acl *vfs_set_acl_prepare(struct user_namespace *mnt_userns,