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![Darrick J. Wong](/assets/img/avatar_default.png)
Files containing metadata (quota records, rt bitmap and summary info) are fully managed by the filesystem, which means that all resource cleanup must be explicit, not automatic. This means that they should never be subjected automatic to post-eof truncation, nor should they be freed automatically even if the link count drops to zero. In other words, xfs_inactive() should leave these files alone. Add the necessary predicate functions to make this happen. This adds a second layer of prevention for the kinds of fs corruption that was fixed by commitf4c32e87de
. If we ever decide to support removing metadata files, we should make all those metadata updates explicit. Rearrange the order of #includes to fix compiler errors, since xfs_mount.h is supposed to be included before xfs_inode.h Followup-to:f4c32e87de
("xfs: fix realtime bitmap/summary file truncation when growing rt volume") Signed-off-by: Darrick J. Wong <djwong@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de>
216 lines
4.8 KiB
C
216 lines
4.8 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/*
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* Copyright (C) 2008 Christoph Hellwig.
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* Portions Copyright (C) 2000-2008 Silicon Graphics, Inc.
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*/
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#include "xfs.h"
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#include "xfs_shared.h"
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#include "xfs_format.h"
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#include "xfs_log_format.h"
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#include "xfs_da_format.h"
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#include "xfs_trans_resv.h"
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#include "xfs_mount.h"
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#include "xfs_inode.h"
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#include "xfs_attr.h"
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#include "xfs_acl.h"
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#include "xfs_da_btree.h"
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#include <linux/posix_acl_xattr.h>
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static int
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xfs_xattr_get(const struct xattr_handler *handler, struct dentry *unused,
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struct inode *inode, const char *name, void *value, size_t size)
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{
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struct xfs_da_args args = {
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.dp = XFS_I(inode),
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.attr_filter = handler->flags,
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.name = name,
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.namelen = strlen(name),
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.value = value,
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.valuelen = size,
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};
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int error;
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error = xfs_attr_get(&args);
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if (error)
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return error;
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return args.valuelen;
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}
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static int
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xfs_xattr_set(const struct xattr_handler *handler,
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struct user_namespace *mnt_userns, struct dentry *unused,
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struct inode *inode, const char *name, const void *value,
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size_t size, int flags)
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{
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struct xfs_da_args args = {
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.dp = XFS_I(inode),
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.attr_filter = handler->flags,
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.attr_flags = flags,
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.name = name,
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.namelen = strlen(name),
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.value = (void *)value,
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.valuelen = size,
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};
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int error;
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error = xfs_attr_set(&args);
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if (!error && (handler->flags & XFS_ATTR_ROOT))
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xfs_forget_acl(inode, name);
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return error;
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}
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static const struct xattr_handler xfs_xattr_user_handler = {
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.prefix = XATTR_USER_PREFIX,
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.flags = 0, /* no flags implies user namespace */
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.get = xfs_xattr_get,
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.set = xfs_xattr_set,
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};
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static const struct xattr_handler xfs_xattr_trusted_handler = {
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.prefix = XATTR_TRUSTED_PREFIX,
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.flags = XFS_ATTR_ROOT,
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.get = xfs_xattr_get,
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.set = xfs_xattr_set,
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};
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static const struct xattr_handler xfs_xattr_security_handler = {
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.prefix = XATTR_SECURITY_PREFIX,
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.flags = XFS_ATTR_SECURE,
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.get = xfs_xattr_get,
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.set = xfs_xattr_set,
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};
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const struct xattr_handler *xfs_xattr_handlers[] = {
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&xfs_xattr_user_handler,
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&xfs_xattr_trusted_handler,
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&xfs_xattr_security_handler,
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#ifdef CONFIG_XFS_POSIX_ACL
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&posix_acl_access_xattr_handler,
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&posix_acl_default_xattr_handler,
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#endif
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NULL
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};
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static void
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__xfs_xattr_put_listent(
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struct xfs_attr_list_context *context,
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char *prefix,
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int prefix_len,
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unsigned char *name,
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int namelen)
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{
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char *offset;
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int arraytop;
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if (context->count < 0 || context->seen_enough)
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return;
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if (!context->buffer)
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goto compute_size;
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arraytop = context->count + prefix_len + namelen + 1;
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if (arraytop > context->firstu) {
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context->count = -1; /* insufficient space */
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context->seen_enough = 1;
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return;
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}
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offset = context->buffer + context->count;
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strncpy(offset, prefix, prefix_len);
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offset += prefix_len;
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strncpy(offset, (char *)name, namelen); /* real name */
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offset += namelen;
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*offset = '\0';
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compute_size:
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context->count += prefix_len + namelen + 1;
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return;
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}
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static void
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xfs_xattr_put_listent(
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struct xfs_attr_list_context *context,
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int flags,
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unsigned char *name,
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int namelen,
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int valuelen)
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{
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char *prefix;
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int prefix_len;
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ASSERT(context->count >= 0);
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if (flags & XFS_ATTR_ROOT) {
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#ifdef CONFIG_XFS_POSIX_ACL
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if (namelen == SGI_ACL_FILE_SIZE &&
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strncmp(name, SGI_ACL_FILE,
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SGI_ACL_FILE_SIZE) == 0) {
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__xfs_xattr_put_listent(
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context, XATTR_SYSTEM_PREFIX,
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XATTR_SYSTEM_PREFIX_LEN,
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XATTR_POSIX_ACL_ACCESS,
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strlen(XATTR_POSIX_ACL_ACCESS));
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} else if (namelen == SGI_ACL_DEFAULT_SIZE &&
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strncmp(name, SGI_ACL_DEFAULT,
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SGI_ACL_DEFAULT_SIZE) == 0) {
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__xfs_xattr_put_listent(
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context, XATTR_SYSTEM_PREFIX,
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XATTR_SYSTEM_PREFIX_LEN,
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XATTR_POSIX_ACL_DEFAULT,
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strlen(XATTR_POSIX_ACL_DEFAULT));
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}
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#endif
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/*
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* Only show root namespace entries if we are actually allowed to
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* see them.
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*/
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if (!capable(CAP_SYS_ADMIN))
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return;
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prefix = XATTR_TRUSTED_PREFIX;
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prefix_len = XATTR_TRUSTED_PREFIX_LEN;
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} else if (flags & XFS_ATTR_SECURE) {
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prefix = XATTR_SECURITY_PREFIX;
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prefix_len = XATTR_SECURITY_PREFIX_LEN;
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} else {
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prefix = XATTR_USER_PREFIX;
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prefix_len = XATTR_USER_PREFIX_LEN;
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}
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__xfs_xattr_put_listent(context, prefix, prefix_len, name,
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namelen);
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return;
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}
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ssize_t
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xfs_vn_listxattr(
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struct dentry *dentry,
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char *data,
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size_t size)
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{
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struct xfs_attr_list_context context;
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struct inode *inode = d_inode(dentry);
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int error;
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/*
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* First read the regular on-disk attributes.
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*/
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memset(&context, 0, sizeof(context));
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context.dp = XFS_I(inode);
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context.resynch = 1;
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context.buffer = size ? data : NULL;
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context.bufsize = size;
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context.firstu = context.bufsize;
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context.put_listent = xfs_xattr_put_listent;
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error = xfs_attr_list(&context);
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if (error)
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return error;
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if (context.count < 0)
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return -ERANGE;
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return context.count;
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}
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