[PATCH 49/59] CRED: Wrap task credential accesses in the SYSV IPC subsystem

David Howells
2008-08-27T14:00:24Z

ipc/mqueue.c | 6 +++---
ipc/shm.c | 5 +++--
ipc/util.c | 18 +++++++++++++-----
3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 96fb36c..51d9588 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -109,8 +109,8 @@ static struct inode *mqueue_get_inode(struct super_block *sb, int mode,
inode = new_inode(sb);
if (inode) {
inode->i_mode = mode;
- inode->i_uid = current->fsuid;
- inode->i_gid = current->fsgid;
+ inode->i_uid = current_fsuid();
+ inode->i_gid = current_fsgid();
inode->i_blocks = 0;
inode->i_mtime = inode->i_ctime = inode->i_atime =
CURRENT_TIME;
@@ -499,7 +499,7 @@ static void __do_notify(struct mqueue_inode_info *info)
sig_i.si_code = SI_MESGQ;
sig_i.si_value = info->notify.sigev_value;
sig_i.si_pid = task_tgid_vnr(current);
- sig_i.si_uid = current->uid;
+ sig_i.si_uid = current_uid();

kill_pid_info(info->notify.sigev_signo,
&sig_i, info->notify_owner);
diff --git a/ipc/shm.c b/ipc/shm.c
index e77ec69..c46a7e6 100644
--- a/ipc/shm.c
+++ b/ipc/shm.c
@@ -748,9 +748,10 @@ asmlinkage long sys_shmctl(int shmid, int cmd, struct shmid_ds __user *buf)
goto out_unlock;

if (!capable(CAP_IPC_LOCK)) {
+ uid_t euid = current_euid();
err = -EPERM;
- if (current->euid != shp->shm_perm.uid &&
- current->euid != shp->shm_perm.cuid)
+ if (euid != shp->shm_perm.uid &&
+ euid != shp->shm_perm.cuid)
goto out_unlock;
if (cmd == SHM_LOCK &&
!current->signal->rlim[RLIMIT_MEMLOCK].rlim_cur)
diff --git a/ipc/util.c b/ipc/util.c
index 49b3ea6..c8a7670 100644
--- a/ipc/util.c
+++ b/ipc/util.c
@@ -258,6 +258,8 @@ int ipc_get_maxid(struct ipc_ids *ids)

int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)
{
+ uid_t euid;
+ gid_t egid;
int id, err;

if (size > IPCMNI)
@@ -272,8 +274,9 @@ int ipc_addid(struct ipc_ids* ids, struct kern_ipc_perm* new, int size)

ids->in_use++;

- new->cuid = new->uid = current->euid;
- new->gid = new->cgid = current->egid;
+ current_euid_egid(&euid, &egid);
+ new->cuid = new->uid = euid;
+ new->gid = new->cgid = egid;

new->seq = ids->seq++;
if(ids->seq > ids->seq_max)
@@ -616,13 +619,15 @@ void ipc_rcu_putref(void *ptr)

int ipcperms (struct kern_ipc_perm *ipcp, short flag)
{ /* flag will most probably be 0 or S_...UGO from <linux/stat.h> */
+ uid_t euid = current_euid();
int requested_mode, granted_mode, err;

if (unlikely((err = audit_ipc_obj(ipcp))))
return err;
requested_mode = (flag >> 6) | (flag >> 3) | flag;
granted_mode = ipcp->mode;
- if (current->euid == ipcp->cuid || current->euid == ipcp->uid)
+ if (euid == ipcp->cuid ||
+ euid == ipcp->uid)
granted_mode >>= 6;
else if (in_group_p(ipcp->cgid) || in_group_p(ipcp->gid))
granted_mode >>= 3;
@@ -784,6 +789,7 @@ struct kern_ipc_perm *ipcctl_pre_down(struct ipc_ids *ids, int id, int cmd,
struct ipc64_perm *perm, int extra_perm)
{
struct kern_ipc_perm *ipcp;
+ uid_t euid;
int err;

down_write(&ids->rw_mutex);
@@ -803,8 +809,10 @@ struct kern_ipc_perm *ipcctl_pre_down(struct ipc_ids *ids, int id, int cmd,
if (err)
goto out_unlock;
}
- if (current->euid == ipcp->cuid ||
- current->euid == ipcp->uid || capable(CAP_SYS_ADMIN))
+
+ euid = current_euid();
+ if (euid == ipcp->cuid ||
+ euid == ipcp->uid || capable(CAP_SYS_ADMIN))
return ipcp;

err = -EPERM;