27 Jun
2014
27 Jun
'14
5:05 p.m.
foo = *((uintXX_t *) TLVP_VAL(...) can lead to unaligned access. To
prevent that use tlvp_valXX_unal() to get the values.
---
openbsc/src/libbsc/abis_rsl.c | 10 +++++-----
openbsc/src/osmo-bsc/osmo_bsc_bssap.c | 2 +-
openbsc/src/osmo-bsc_nat/bsc_mgcp_utils.c | 2 +-
3 files changed, 7 insertions(+), 7 deletions(-)
diff --git a/openbsc/src/libbsc/abis_rsl.c b/openbsc/src/libbsc/abis_rsl.c
index 748ab7e..d193078 100644
--- a/openbsc/src/libbsc/abis_rsl.c
+++ b/openbsc/src/libbsc/abis_rsl.c
@@ -1804,20 +1804,20 @@ static void ipac_parse_rtp(struct gsm_lchan *lchan, struct
tlv_parsed *tv)
uint16_t port, conn_id;
if (TLVP_PRESENT(tv, RSL_IE_IPAC_LOCAL_IP)) {
- ip.s_addr = *((uint32_t *) TLVP_VAL(tv, RSL_IE_IPAC_LOCAL_IP));
+ ip.s_addr = tlvp_val32_unal(tv, RSL_IE_IPAC_LOCAL_IP);
DEBUGPC(DRSL, "LOCAL_IP=%s ", inet_ntoa(ip));
lchan->abis_ip.bound_ip = ntohl(ip.s_addr);
}
if (TLVP_PRESENT(tv, RSL_IE_IPAC_LOCAL_PORT)) {
- port = *((uint16_t *) TLVP_VAL(tv, RSL_IE_IPAC_LOCAL_PORT));
+ port = tlvp_val16_unal(tv, RSL_IE_IPAC_LOCAL_PORT);
port = ntohs(port);
DEBUGPC(DRSL, "LOCAL_PORT=%u ", port);
lchan->abis_ip.bound_port = port;
}
if (TLVP_PRESENT(tv, RSL_IE_IPAC_CONN_ID)) {
- conn_id = *((uint16_t *) TLVP_VAL(tv, RSL_IE_IPAC_CONN_ID));
+ conn_id = tlvp_val16_unal(tv, RSL_IE_IPAC_CONN_ID);
conn_id = ntohs(conn_id);
DEBUGPC(DRSL, "CON_ID=%u ", conn_id);
lchan->abis_ip.conn_id = conn_id;
@@ -1838,13 +1838,13 @@ static void ipac_parse_rtp(struct gsm_lchan *lchan, struct
tlv_parsed *tv)
}
if (TLVP_PRESENT(tv, RSL_IE_IPAC_REMOTE_IP)) {
- ip.s_addr = *((uint32_t *) TLVP_VAL(tv, RSL_IE_IPAC_REMOTE_IP));
+ ip.s_addr = tlvp_val32_unal(tv, RSL_IE_IPAC_REMOTE_IP);
DEBUGPC(DRSL, "REMOTE_IP=%s ", inet_ntoa(ip));
lchan->abis_ip.connect_ip = ntohl(ip.s_addr);
}
if (TLVP_PRESENT(tv, RSL_IE_IPAC_REMOTE_PORT)) {
- port = *((uint16_t *) TLVP_VAL(tv, RSL_IE_IPAC_REMOTE_PORT));
+ port = tlvp_val16_unal(tv, RSL_IE_IPAC_REMOTE_PORT);
port = ntohs(port);
DEBUGPC(DRSL, "REMOTE_PORT=%u ", port);
lchan->abis_ip.connect_port = port;
diff --git a/openbsc/src/osmo-bsc/osmo_bsc_bssap.c
b/openbsc/src/osmo-bsc/osmo_bsc_bssap.c
index c2c2417..f58d96f 100644
--- a/openbsc/src/osmo-bsc/osmo_bsc_bssap.c
+++ b/openbsc/src/osmo-bsc/osmo_bsc_bssap.c
@@ -135,7 +135,7 @@ static int bssmap_handle_paging(struct osmo_msc_data *msc,
if (TLVP_PRESENT(&tp, GSM0808_IE_TMSI) &&
TLVP_LEN(&tp, GSM0808_IE_TMSI) == 4) {
- tmsi = ntohl(*(uint32_t *) TLVP_VAL(&tp, GSM0808_IE_TMSI));
+ tmsi = ntohl(tlvp_val32_unal(&tp, GSM0808_IE_TMSI));
}
/*
diff --git a/openbsc/src/osmo-bsc_nat/bsc_mgcp_utils.c
b/openbsc/src/osmo-bsc_nat/bsc_mgcp_utils.c
index 22b8a35..e13827b 100644
--- a/openbsc/src/osmo-bsc_nat/bsc_mgcp_utils.c
+++ b/openbsc/src/osmo-bsc_nat/bsc_mgcp_utils.c
@@ -191,7 +191,7 @@ int bsc_mgcp_assign_patch(struct nat_sccp_connection *con, struct msgb
*msg)
return -1;
}
- cic = ntohs(*(uint16_t *)TLVP_VAL(&tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE));
+ cic = ntohs(tlvp_val16_unal(&tp, GSM0808_IE_CIRCUIT_IDENTITY_CODE));
timeslot = cic & 0x1f;
multiplex = (cic & ~0x1f) >> 5;
--
1.8.4.2
27 Jun
27 Jun
5:05 p.m.
New subject: [openbsc 2/3] gprs_llc: Prevent llme_alloc/lle_init from reading invalid memory
Make the llc_default_params structure from which data is initialized
large enough. Otherwise address sanitizer complains with out-of-bounds
reads.
---
openbsc/src/gprs/gprs_llc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/openbsc/src/gprs/gprs_llc.c b/openbsc/src/gprs/gprs_llc.c
index 70fe9dd..e6b1f07 100644
--- a/openbsc/src/gprs/gprs_llc.c
+++ b/openbsc/src/gprs/gprs_llc.c
@@ -84,7 +84,7 @@ static int _bssgp_tx_dl_ud(struct msgb *msg, struct sgsn_mm_ctx *mmctx)
/* Section 8.9.9 LLC layer parameter default values */
-static const struct gprs_llc_params llc_default_params[] = {
+static const struct gprs_llc_params llc_default_params[NUM_SAPIS] = {
[1] = {
.t200_201 = 5,
.n200 = 3,
--
1.8.4.2
5:05 p.m.
New subject: [openbsc 3/3] libtrau: Fix off-by-one read access to gsm_fr_map
Address sanitizer complains with a buffer overflow to the end of
gsm_fr_map:
ERROR: AddressSanitizer: global-buffer-overflow on address 0x00000044f76c at pc 0x43c0dd
bp 0x7fff18389db0 sp 0x7fff18389da8
READ of size 1 at 0x00000044f76c thread T0
#0 0x43c0dc in trau_encode_fr
/home/alphaone/scm/osmo/openbsc/openbsc/src/libtrau/trau_mux.c:441
#1 0x42fad6 in test_trau_fr_efr
/home/alphaone/scm/osmo/openbsc/openbsc/tests/trau/trau_test.c:35
#2 0x4308f4 in main /home/alphaone/scm/osmo/openbsc/openbsc/tests/trau/trau_test.c:70
#3 0x7f96e8cf04bc (/lib64/libc.so.6+0x224bc)
#4 0x42f7ec (/home/alphaone/scm/osmo/openbsc/openbsc/tests/trau/trau_test+0x42f7ec)
0x00000044f76c is located 52 bytes to the left of global variable
'c_bits_check_fr' from 'trau_mux.c' (0x44f7a0) of size 5
0x00000044f76c is located 0 bytes to the right of global variable 'gsm_fr_map'
from 'trau_mux.c' (0x44f720) of size 76
SUMMARY: AddressSanitizer: global-buffer-overflow
/home/alphaone/scm/osmo/openbsc/openbsc/src/libtrau/trau_mux.c:441 trau_encode_fr
In the last iteration of the loop k is already set to the next element
in gsm_fr_map which leads to an out-of-bounds read. Instead decrement k
at the end of the loop and put the check before the data assignment.
This is functionally equivalent as k is never < 0 initially.
This happens in trau_decode_fr as well.
---
openbsc/src/libtrau/trau_mux.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/openbsc/src/libtrau/trau_mux.c b/openbsc/src/libtrau/trau_mux.c
index 4f159e4..9b93eda 100644
--- a/openbsc/src/libtrau/trau_mux.c
+++ b/openbsc/src/libtrau/trau_mux.c
@@ -234,13 +234,14 @@ struct msgb *trau_decode_fr(uint32_t callref,
l = 0; /* counts element bits */
o = 0; /* offset input bits */
while (i < 260) {
- data[j/8] |= (tf->d_bits[k+o] << (7-(j%8)));
- if (--k < 0) {
+ if (k < 0) {
o += gsm_fr_map[l];
k = gsm_fr_map[++l]-1;
}
+ data[j/8] |= (tf->d_bits[k+o] << (7-(j%8)));
i++;
j++;
+ k--;
}
frame->msg_type = GSM_TCHF_FRAME;
frame->callref = callref;
@@ -435,16 +436,14 @@ void trau_encode_fr(struct decoded_trau_frame *tf,
l = 0; /* counts element bits */
o = 0; /* offset output bits */
while (i < 260) {
- tf->d_bits[k+o] = (data[j/8] >> (7-(j%8))) & 1;
- /* to avoid out-of-bounds access in gsm_fr_map[++l] */
- if (i == 259)
- break;
- if (--k < 0) {
+ if (k < 0) {
o += gsm_fr_map[l];
k = gsm_fr_map[++l]-1;
}
+ tf->d_bits[k+o] = (data[j/8] >> (7-(j%8))) & 1;
i++;
j++;
+ k--;
}
}
--
1.8.4.2
3613
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3613
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Daniel Willmann