Skip to content

Commit

Permalink
afs: Prevent callback expiry timer overflow
Browse files Browse the repository at this point in the history
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: Tina Ruchandani <[email protected]>
Signed-off-by: David Howells <[email protected]>
  • Loading branch information
Tinabr7 authored and dhowells committed Mar 16, 2017
1 parent 8a79790 commit 56e7143
Show file tree
Hide file tree
Showing 3 changed files with 7 additions and 6 deletions.
2 changes: 1 addition & 1 deletion fs/afs/fsclient.c
Original file line number Diff line number Diff line change
Expand Up @@ -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;
}

Expand Down
7 changes: 4 additions & 3 deletions fs/afs/inode.c
Original file line number Diff line number Diff line change
Expand Up @@ -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();
}
}

Expand Down Expand Up @@ -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 {
Expand Down
4 changes: 2 additions & 2 deletions fs/afs/internal.h
Original file line number Diff line number Diff line change
Expand Up @@ -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 */
Expand Down

0 comments on commit 56e7143

Please sign in to comment.