Commit 56e71431 authored by Tina Ruchandani's avatar Tina Ruchandani Committed by David Howells
Browse files

afs: Prevent callback expiry timer overflow 



get_seconds() returns real wall-clock seconds. On 32-bit systems
this value will overflow in year 2038 and beyond. This patch changes
afs_vnode record to use ktime_get_real_seconds() instead, for the
fields cb_expires and cb_expires_at.

Signed-off-by: default avatarTina Ruchandani <ruchandani.tina@gmail.com>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
parent 8a79790b

fs/afs/fsclient.c

+1 −1
Original line number Diff line number Diff line
@@ -145,7 +145,7 @@ static void xdr_decode_AFSCallBack(const __be32 **_bp, struct afs_vnode *vnode) 
	vnode->cb_version	= ntohl(*bp++);

	vnode->cb_expiry	= ntohl(*bp++);

	vnode->cb_type		= ntohl(*bp++);

	vnode->cb_expires	= vnode->cb_expiry + get_seconds();

	vnode->cb_expires	= vnode->cb_expiry + ktime_get_real_seconds();

	*_bp = bp;

}

fs/afs/inode.c

+4 −3
Original line number Diff line number Diff line
@@ -246,12 +246,13 @@ struct inode *afs_iget(struct super_block *sb, struct key *key, 
			vnode->cb_version = 0;

			vnode->cb_expiry = 0;

			vnode->cb_type = 0;

			vnode->cb_expires = get_seconds();

			vnode->cb_expires = ktime_get_real_seconds();

		} else {

			vnode->cb_version = cb->version;

			vnode->cb_expiry = cb->expiry;

			vnode->cb_type = cb->type;

			vnode->cb_expires = vnode->cb_expiry + get_seconds();

			vnode->cb_expires = vnode->cb_expiry +

				ktime_get_real_seconds();

		}

	}
@@ -324,7 +325,7 @@ int afs_validate(struct afs_vnode *vnode, struct key *key) 
	    !test_bit(AFS_VNODE_CB_BROKEN, &vnode->flags) &&

	    !test_bit(AFS_VNODE_MODIFIED, &vnode->flags) &&

	    !test_bit(AFS_VNODE_ZAP_DATA, &vnode->flags)) {

		if (vnode->cb_expires < get_seconds() + 10) {

		if (vnode->cb_expires < ktime_get_real_seconds() + 10) {

			_debug("callback expired");

			set_bit(AFS_VNODE_CB_BROKEN, &vnode->flags);

		} else {

fs/afs/internal.h

+2 −2
Original line number Diff line number Diff line
@@ -377,8 +377,8 @@ struct afs_vnode { 
	struct rb_node		server_rb;	/* link in server->fs_vnodes */

	struct rb_node		cb_promise;	/* link in server->cb_promises */

	struct work_struct	cb_broken_work;	/* work to be done on callback break */

	time_t			cb_expires;	/* time at which callback expires */

	time_t			cb_expires_at;	/* time used to order cb_promise */

	time64_t		cb_expires;	/* time at which callback expires */

	time64_t		cb_expires_at;	/* time used to order cb_promise */

	unsigned		cb_version;	/* callback version */

	unsigned		cb_expiry;	/* callback expiry time */

	afs_callback_type_t	cb_type;	/* type of callback */

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