libceph: NULL deref on crush_decode() error path

PATCH Applied Dan Carpenter 2 participants 2 messages May 23, 2017

Subsystems (2)

Kernel janitors Ceph common code (libceph)

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Dan Carpenter

author

2017-05-23 14:25 UTC #0 lore raw

PATCH 1/1 libceph: NULL deref on crush_decode() error path

If there is not enough space then ceph_decode_32_safe() does a goto bad. We need to return an error code in that situation. The current code returns ERR_PTR(0) which is NULL. The callers are not expecting that and it results in a NULL dereference.

Fixes f24e9980eb86 ("ceph: OSD client")

Signed-off-by Dan Carpenter <[email protected]>

net/ceph/osdmap.c +1 -0

index ffe9e904d4d1..55e3a477f92d 100644
@@ -317,6 +317,7 @@ static struct crush_map *crush_decode(void *pbyval, void *end)
 		u32 yes;
 		struct crush_rule *r;
 
+		err = -EINVAL;
 		ceph_decode_32_safe(p, end, yes, bad);
 		if (!yes) {
 			dout("crush_decode NO rule %d off %x %p to %p\n",

Ilya Dryomov

maintainer Applied

2017-05-23 16:23 UTC #1 lore raw

Quoted 13 lines · Dan Carpenter

If there is not enough space then ceph_decode_32_safe() does a goto bad. We need to return an error code in that situation. The current code returns ERR_PTR(0) which is NULL. The callers are not expecting that and it results in a NULL dereference.
Fixes f24e9980eb86 ("ceph: OSD client")
Signed-off-by Dan Carpenter <[email protected]>
net/ceph/osdmap.c +0 -0
index ffe9e904d4d1..55e3a477f92d 100644

net/ceph/osdmap.c static struct crush_map *crush_decode(void *pbyval, void *end) · line 323

Quoted 7 lines

net/ceph/osdmap.c +1 -0

@@ -317,6 +317,7 @@ static struct crush_map *crush_decode(void *pbyval, void *end)
                u32 yes;
                struct crush_rule *r;
 
+               err = -EINVAL;
                ceph_decode_32_safe(p, end, yes, bad);
                if (!yes) {
                        dout("crush_decode NO rule %d off %x %p to %p\n",

Applied.

Thanks,

Ilya