On 10/18/2018 03:47 AM, Ondrej Mosnacek wrote:
Do the LE conversions before doing the Infiniband-related range checks.
The incorrect checks are otherwise causing a failure to load any policy
with an ibendportcon rule on BE systems. This can be reproduced by
running (on e.g. ppc64):
cat >my_module.cil <<EOF
(type test_ibendport_t)
(roletype object_r test_ibendport_t)
(ibendportcon mlx4_0 1 (system_u object_r test_ibendport_t ((s0) (s0))))
EOF
semodule -i my_module.cil
Also, fix loading/storing the 64-bit subnet prefix for OCON_IBPKEY to
use a correctly aligned buffer.
Finally, do not use the 'nodebuf' (u32) buffer where 'buf' (__le32)
should be used instead.
Tested internally on a ppc64 machine with a RHEL 7 kernel with this
patch applied.
Cc: Daniel Jurgens <danielj@xxxxxxxxxxxx>
Cc: Eli Cohen <eli@xxxxxxxxxxxx>
Cc: James Morris <jmorris@xxxxxxxxx>
Cc: Doug Ledford <dledford@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # 4.13+
Fixes: a806f7a1616f ("selinux: Create policydb version for Infiniband support")
Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx>
---
security/selinux/ss/policydb.c | 46 +++++++++++++++++++++++-----------
1 file changed, 32 insertions(+), 14 deletions(-)
Changes in v4:
- defer assignment to 16-bit struct fields to after the range check
Changes in v3:
- use separate buffer for the 64-bit subnet_prefix
- add comments on the byte ordering of subnet_prefix
- deduplicate the le32_to_cpu() calls from checks
Changes in v2:
- add reproducer to commit message
- update e-mail address of James Morris
- better Cc also the old SELinux ML
diff --git a/security/selinux/ss/policydb.c b/security/selinux/ss/policydb.c
index f4eadd3f7350..d50668006a52 100644
--- a/security/selinux/ss/policydb.c
+++ b/security/selinux/ss/policydb.c
@@ -2108,6 +2108,7 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info,
{
int i, j, rc;
u32 nel, len;
+ __be64 prefixbuf[1];
__le32 buf[3];
struct ocontext *l, *c;
u32 nodebuf[8];
@@ -2217,21 +2218,30 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info,
goto out;
break;
}
- case OCON_IBPKEY:
- rc = next_entry(nodebuf, fp, sizeof(u32) * 4);
+ case OCON_IBPKEY: {
+ u32 pkey_lo, pkey_hi;
+
+ rc = next_entry(prefixbuf, fp, sizeof(u64));
+ if (rc)
+ goto out;
+
+ /* we need to have subnet_prefix in CPU order */
+ c->u.ibpkey.subnet_prefix = be64_to_cpu(prefixbuf[0]);
+
+ rc = next_entry(buf, fp, sizeof(u32) * 2);
if (rc)
goto out;
- c->u.ibpkey.subnet_prefix = be64_to_cpu(*((__be64 *)nodebuf));
+ pkey_lo = le32_to_cpu(buf[0]);
+ pkey_hi = le32_to_cpu(buf[1]);
- if (nodebuf[2] > 0xffff ||
- nodebuf[3] > 0xffff) {
+ if (pkey_lo > U16_MAX || pkey_hi > U16_MAX) {
rc = -EINVAL;
goto out;
}
- c->u.ibpkey.low_pkey = le32_to_cpu(nodebuf[2]);
- c->u.ibpkey.high_pkey = le32_to_cpu(nodebuf[3]);
+ c->u.ibpkey.low_pkey = pkey_lo;
+ c->u.ibpkey.high_pkey = pkey_hi;
rc = context_read_and_validate(&c->context[0],
p,
@@ -2239,6 +2249,7 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info,
if (rc)
goto out;
break;
+ }
case OCON_IBENDPORT:
rc = next_entry(buf, fp, sizeof(u32) * 2);
if (rc)
@@ -2249,13 +2260,14 @@ static int ocontext_read(struct policydb *p, struct policydb_compat_info *info,
if (rc)
goto out;
- if (buf[1] > 0xff || buf[1] == 0) {
+ c->u.ibendport.port = le32_to_cpu(buf[1]);
ibendport.port is a u8 here, same issue.
+
+ if (c->u.ibendport.port > 0xff ||
+ c->u.ibendport.port == 0) {
rc = -EINVAL;
goto out;
}
- c->u.ibendport.port = le32_to_cpu(buf[1]);
-
rc = context_read_and_validate(&c->context[0],
p,
fp);
@@ -3105,6 +3117,7 @@ static int ocontext_write(struct policydb *p, struct policydb_compat_info *info,
{
unsigned int i, j, rc;
size_t nel, len;
+ __be64 prefixbuf[1];
__le32 buf[3];
u32 nodebuf[8];
struct ocontext *c;
@@ -3192,12 +3205,17 @@ static int ocontext_write(struct policydb *p, struct policydb_compat_info *info,
return rc;
break;
case OCON_IBPKEY:
- *((__be64 *)nodebuf) = cpu_to_be64(c->u.ibpkey.subnet_prefix);
+ /* subnet_prefix is in CPU order */
+ prefixbuf[0] = cpu_to_be64(c->u.ibpkey.subnet_prefix);
- nodebuf[2] = cpu_to_le32(c->u.ibpkey.low_pkey);
- nodebuf[3] = cpu_to_le32(c->u.ibpkey.high_pkey);
+ rc = put_entry(prefixbuf, sizeof(u64), 1, fp);
+ if (rc)
+ return rc;
- rc = put_entry(nodebuf, sizeof(u32), 4, fp);
+ buf[0] = cpu_to_le32(c->u.ibpkey.low_pkey);
+ buf[1] = cpu_to_le32(c->u.ibpkey.high_pkey);
+
+ rc = put_entry(buf, sizeof(u32), 2, fp);
if (rc)
return rc;
rc = context_write(p, &c->context[0], fp);
