From 786534b92f3ce68f4afc8a761c80b76887797b0a Mon Sep 17 00:00:00 2001 From: Andreas Gruenbacher Date: Wed, 2 Dec 2015 14:44:39 +0100 Subject: [PATCH] tmpfs: listxattr should include POSIX ACL xattrs When a file on tmpfs has an ACL or a Default ACL, listxattr should include the corresponding xattr name. Signed-off-by: Andreas Gruenbacher Reviewed-by: James Morris Cc: Hugh Dickins Cc: linux-mm@kvack.org Signed-off-by: Al Viro --- fs/kernfs/inode.c | 2 +- fs/xattr.c | 53 ++++++++++++++++++++++++++++++------------- include/linux/xattr.h | 3 ++- mm/shmem.c | 2 +- 4 files changed, 41 insertions(+), 19 deletions(-) diff --git a/fs/kernfs/inode.c b/fs/kernfs/inode.c index f97e1f7790b1..16405ae88d2d 100644 --- a/fs/kernfs/inode.c +++ b/fs/kernfs/inode.c @@ -230,7 +230,7 @@ ssize_t kernfs_iop_listxattr(struct dentry *dentry, char *buf, size_t size) if (!attrs) return -ENOMEM; - return simple_xattr_list(&attrs->xattrs, buf, size); + return simple_xattr_list(d_inode(dentry), &attrs->xattrs, buf, size); } static inline void set_default_inode_attr(struct inode *inode, umode_t mode) diff --git a/fs/xattr.c b/fs/xattr.c index 4ef8b378dc90..c3af6c9670cb 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -921,38 +921,59 @@ static bool xattr_is_trusted(const char *name) return !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN); } +static int xattr_list_one(char **buffer, ssize_t *remaining_size, + const char *name) +{ + size_t len = strlen(name) + 1; + if (*buffer) { + if (*remaining_size < len) + return -ERANGE; + memcpy(*buffer, name, len); + *buffer += len; + } + *remaining_size -= len; + return 0; +} + /* * xattr LIST operation for in-memory/pseudo filesystems */ -ssize_t simple_xattr_list(struct simple_xattrs *xattrs, char *buffer, - size_t size) +ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, + char *buffer, size_t size) { bool trusted = capable(CAP_SYS_ADMIN); struct simple_xattr *xattr; - size_t used = 0; + ssize_t remaining_size = size; + int err; + +#ifdef CONFIG_FS_POSIX_ACL + if (inode->i_acl) { + err = xattr_list_one(&buffer, &remaining_size, + XATTR_NAME_POSIX_ACL_ACCESS); + if (err) + return err; + } + if (inode->i_default_acl) { + err = xattr_list_one(&buffer, &remaining_size, + XATTR_NAME_POSIX_ACL_DEFAULT); + if (err) + return err; + } +#endif spin_lock(&xattrs->lock); list_for_each_entry(xattr, &xattrs->head, list) { - size_t len; - /* skip "trusted." attributes for unprivileged callers */ if (!trusted && xattr_is_trusted(xattr->name)) continue; - len = strlen(xattr->name) + 1; - used += len; - if (buffer) { - if (size < used) { - used = -ERANGE; - break; - } - memcpy(buffer, xattr->name, len); - buffer += len; - } + err = xattr_list_one(&buffer, &remaining_size, xattr->name); + if (err) + return err; } spin_unlock(&xattrs->lock); - return used; + return size - remaining_size; } /* diff --git a/include/linux/xattr.h b/include/linux/xattr.h index 4dd40cb2c07b..d23ce8e9af6f 100644 --- a/include/linux/xattr.h +++ b/include/linux/xattr.h @@ -104,7 +104,8 @@ int simple_xattr_get(struct simple_xattrs *xattrs, const char *name, void *buffer, size_t size); int simple_xattr_set(struct simple_xattrs *xattrs, const char *name, const void *value, size_t size, int flags); -ssize_t simple_xattr_list(struct simple_xattrs *xattrs, char *buffer, size_t size); +ssize_t simple_xattr_list(struct inode *inode, struct simple_xattrs *xattrs, char *buffer, + size_t size); void simple_xattr_list_add(struct simple_xattrs *xattrs, struct simple_xattr *new_xattr); diff --git a/mm/shmem.c b/mm/shmem.c index fdfe6c8dddfc..297390f4e50f 100644 --- a/mm/shmem.c +++ b/mm/shmem.c @@ -2606,7 +2606,7 @@ static const struct xattr_handler *shmem_xattr_handlers[] = { static ssize_t shmem_listxattr(struct dentry *dentry, char *buffer, size_t size) { struct shmem_inode_info *info = SHMEM_I(d_inode(dentry)); - return simple_xattr_list(&info->xattrs, buffer, size); + return simple_xattr_list(d_inode(dentry), &info->xattrs, buffer, size); } #endif /* CONFIG_TMPFS_XATTR */ -- GitLab