All of lore.kernel.org
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: linux-xfs@vger.kernel.org
Subject: [PATCH 1/4] xfs: clear kernel only flags in XFS_IOC_ATTRMULTI_BY_HANDLE
Date: Tue,  7 Jan 2020 17:54:39 +0100	[thread overview]
Message-ID: <20200107165442.262020-2-hch@lst.de> (raw)
In-Reply-To: <20200107165442.262020-1-hch@lst.de>

Don't allow passing arbitrary flags as they change behavior including
memory allocation that the call stack is not prepared for.

Fixes: ddbca70cc45c ("xfs: allocate xattr buffer on demand")
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 fs/xfs/libxfs/xfs_attr.h | 7 +++++--
 fs/xfs/xfs_ioctl.c       | 2 ++
 fs/xfs/xfs_ioctl32.c     | 2 ++
 3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h
index 94badfa1743e..91c2cb14276e 100644
--- a/fs/xfs/libxfs/xfs_attr.h
+++ b/fs/xfs/libxfs/xfs_attr.h
@@ -26,7 +26,7 @@ struct xfs_attr_list_context;
  *========================================================================*/
 
 
-#define ATTR_DONTFOLLOW	0x0001	/* -- unused, from IRIX -- */
+#define ATTR_DONTFOLLOW	0x0001	/* -- ignored, from IRIX -- */
 #define ATTR_ROOT	0x0002	/* use attrs in root (trusted) namespace */
 #define ATTR_TRUST	0x0004	/* -- unused, from IRIX -- */
 #define ATTR_SECURE	0x0008	/* use attrs in security namespace */
@@ -37,7 +37,10 @@ struct xfs_attr_list_context;
 #define ATTR_KERNOVAL	0x2000	/* [kernel] get attr size only, not value */
 
 #define ATTR_INCOMPLETE	0x4000	/* [kernel] return INCOMPLETE attr keys */
-#define ATTR_ALLOC	0x8000	/* allocate xattr buffer on demand */
+#define ATTR_ALLOC	0x8000	/* [kernel] allocate xattr buffer on demand */
+
+#define ATTR_KERNEL_FLAGS \
+	(ATTR_KERNOTIME | ATTR_KERNOVAL | ATTR_INCOMPLETE | ATTR_ALLOC)
 
 #define XFS_ATTR_FLAGS \
 	{ ATTR_DONTFOLLOW, 	"DONTFOLLOW" }, \
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 7b35d62ede9f..edfbdb8f85e2 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -462,6 +462,8 @@ xfs_attrmulti_by_handle(
 
 	error = 0;
 	for (i = 0; i < am_hreq.opcount; i++) {
+		ops[i].am_flags &= ~ATTR_KERNEL_FLAGS;
+
 		ops[i].am_error = strncpy_from_user((char *)attr_name,
 				ops[i].am_attrname, MAXNAMELEN);
 		if (ops[i].am_error == 0 || ops[i].am_error == MAXNAMELEN)
diff --git a/fs/xfs/xfs_ioctl32.c b/fs/xfs/xfs_ioctl32.c
index c4c4f09113d3..bd9d9ebf85d8 100644
--- a/fs/xfs/xfs_ioctl32.c
+++ b/fs/xfs/xfs_ioctl32.c
@@ -450,6 +450,8 @@ xfs_compat_attrmulti_by_handle(
 
 	error = 0;
 	for (i = 0; i < am_hreq.opcount; i++) {
+		ops[i].am_flags &= ~ATTR_KERNEL_FLAGS;
+
 		ops[i].am_error = strncpy_from_user((char *)attr_name,
 				compat_ptr(ops[i].am_attrname),
 				MAXNAMELEN);
-- 
2.24.1


  reply	other threads:[~2020-01-07 16:54 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-01-07 16:54 attr fixes Christoph Hellwig
2020-01-07 16:54 ` Christoph Hellwig [this message]
2020-01-07 23:23   ` [PATCH 1/4] xfs: clear kernel only flags in XFS_IOC_ATTRMULTI_BY_HANDLE Darrick J. Wong
2020-01-07 16:54 ` [PATCH 2/4] xfs: reject invalid flags combinations " Christoph Hellwig
2020-01-07 16:54 ` [PATCH 3/4] xfs: also remove cached ACLs when removing the underlying attr Christoph Hellwig
2020-01-07 23:23   ` Darrick J. Wong
2020-01-07 16:54 ` [PATCH 4/4] xfs: fix misuse of the XFS_ATTR_INCOMPLETE flag Christoph Hellwig
2020-01-07 23:23 ` attr fixes Darrick J. Wong
2020-01-08  7:04   ` Christoph Hellwig

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20200107165442.262020-2-hch@lst.de \
    --to=hch@lst.de \
    --cc=linux-xfs@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.