diff options
| author | Fabian Frederick <fabf@skynet.be> | 2016-08-02 14:03:07 -0700 |
|---|---|---|
| committer | Ben Hutchings <ben@decadent.org.uk> | 2016-11-20 01:17:04 +0000 |
| commit | 08397b1a5cd433944e424de2be1f92eefb3836c2 (patch) | |
| tree | 6211e08195d68a5c5f0a2959de39b46b4c4a3fc9 | |
| parent | c1103c6d9ce22ed477815249ca5a3c17d5a0af14 (diff) | |
| download | linux-stable-08397b1a5cd433944e424de2be1f92eefb3836c2.tar.gz linux-stable-08397b1a5cd433944e424de2be1f92eefb3836c2.tar.bz2 linux-stable-08397b1a5cd433944e424de2be1f92eefb3836c2.zip | |
sysv, ipc: fix security-layer leaking
commit 9b24fef9f0410fb5364245d6cc2bd044cc064007 upstream.
Commit 53dad6d3a8e5 ("ipc: fix race with LSMs") updated ipc_rcu_putref()
to receive rcu freeing function but used generic ipc_rcu_free() instead
of msg_rcu_free() which does security cleaning.
Running LTP msgsnd06 with kmemleak gives the following:
cat /sys/kernel/debug/kmemleak
unreferenced object 0xffff88003c0a11f8 (size 8):
comm "msgsnd06", pid 1645, jiffies 4294672526 (age 6.549s)
hex dump (first 8 bytes):
1b 00 00 00 01 00 00 00 ........
backtrace:
kmemleak_alloc+0x23/0x40
kmem_cache_alloc_trace+0xe1/0x180
selinux_msg_queue_alloc_security+0x3f/0xd0
security_msg_queue_alloc+0x2e/0x40
newque+0x4e/0x150
ipcget+0x159/0x1b0
SyS_msgget+0x39/0x40
entry_SYSCALL_64_fastpath+0x13/0x8f
Manfred Spraul suggested to fix sem.c as well and Davidlohr Bueso to
only use ipc_rcu_free in case of security allocation failure in newary()
Fixes: 53dad6d3a8e ("ipc: fix race with LSMs")
Link: http://lkml.kernel.org/r/1470083552-22966-1-git-send-email-fabf@skynet.be
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
| -rw-r--r-- | ipc/msg.c | 2 | ||||
| -rw-r--r-- | ipc/sem.c | 12 |
2 files changed, 7 insertions, 7 deletions
diff --git a/ipc/msg.c b/ipc/msg.c index cfc8b388332d..02e72d3db498 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -678,7 +678,7 @@ long do_msgsnd(int msqid, long mtype, void __user *mtext, rcu_read_lock(); ipc_lock_object(&msq->q_perm); - ipc_rcu_putref(msq, ipc_rcu_free); + ipc_rcu_putref(msq, msg_rcu_free); /* raced with RMID? */ if (!ipc_valid_object(&msq->q_perm)) { err = -EIDRM; diff --git a/ipc/sem.c b/ipc/sem.c index 541cb0ff9bd6..fb0c4c96e50a 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -442,7 +442,7 @@ static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns static inline void sem_lock_and_putref(struct sem_array *sma) { sem_lock(sma, NULL, -1); - ipc_rcu_putref(sma, ipc_rcu_free); + ipc_rcu_putref(sma, sem_rcu_free); } static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s) @@ -1385,7 +1385,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, rcu_read_unlock(); sem_io = ipc_alloc(sizeof(ushort)*nsems); if (sem_io == NULL) { - ipc_rcu_putref(sma, ipc_rcu_free); + ipc_rcu_putref(sma, sem_rcu_free); return -ENOMEM; } @@ -1419,20 +1419,20 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, if (nsems > SEMMSL_FAST) { sem_io = ipc_alloc(sizeof(ushort)*nsems); if (sem_io == NULL) { - ipc_rcu_putref(sma, ipc_rcu_free); + ipc_rcu_putref(sma, sem_rcu_free); return -ENOMEM; } } if (copy_from_user(sem_io, p, nsems*sizeof(ushort))) { - ipc_rcu_putref(sma, ipc_rcu_free); + ipc_rcu_putref(sma, sem_rcu_free); err = -EFAULT; goto out_free; } for (i = 0; i < nsems; i++) { if (sem_io[i] > SEMVMX) { - ipc_rcu_putref(sma, ipc_rcu_free); + ipc_rcu_putref(sma, sem_rcu_free); err = -ERANGE; goto out_free; } @@ -1722,7 +1722,7 @@ static struct sem_undo *find_alloc_undo(struct ipc_namespace *ns, int semid) /* step 2: allocate new undo structure */ new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL); if (!new) { - ipc_rcu_putref(sma, ipc_rcu_free); + ipc_rcu_putref(sma, sem_rcu_free); return ERR_PTR(-ENOMEM); } |