phone-side
/
osmocom-bb
mirror of https://gerrit.osmocom.org/osmocom-bb
9
0
Fork 0
Code Issues Releases Wiki Activity

trxcon: do not crash on receipt of 8-PSK modulated bursts 

TRXDv0 PDUs may have 2 additional dummy bytes at the end.  Such
a PDU will crash trxcon if it contains an 8-PSK modulated burst:

  Assert failed phybi->burst_len <= sizeof(bi.burst)

In this case phybi->burst_len would be 444 + 2, while size of the
burst buffer in struct l1sched_burst_ind is limited to the length
of an 8-PSK modulated burst (444).

Change-Id: Icfba986ccf0c696ba019b91575b4d69db001c14f
This commit is contained in:
Vadim Yanitskiy 2023-03-08 02:41:54 +07:00 committed by fixeria
parent 616949a0be
commit 6fe33fd6d4
1 changed files with 19 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
src/host/trxcon/src/trx_if.c
View File

@ -645,9 +645,9 @@ static int trx_data_rx_cb(struct osmo_fd *ofd, unsigned int what)
return read_len;
}
if (read_len < (TRXDv0_HDR_LEN + GSM_NBITS_NB_GMSK_BURST)) {
if (read_len < TRXDv0_HDR_LEN) {
LOGPFSMSL(trx->fi, DTRXD, LOGL_ERROR,
"Got data message with invalid length '%zd'\n", read_len);
"Got malformed TRXD PDU (short length=%zd)\n", read_len);
return -EINVAL;
}
@ -657,6 +657,22 @@ static int trx_data_rx_cb(struct osmo_fd *ofd, unsigned int what)
return -ENOTSUP;
}
read_len -= TRXDv0_HDR_LEN;
switch (read_len) {
/* TRXDv0 PDUs may have 2 dummy bytes at the end */
case GSM_NBITS_NB_GMSK_BURST + 2:
case GSM_NBITS_NB_8PSK_BURST + 2:
read_len -= 2;
break;
case GSM_NBITS_NB_GMSK_BURST:
case GSM_NBITS_NB_8PSK_BURST:
break;
default:
LOGPFSMSL(trx->fi, DTRXD, LOGL_ERROR,
"Got TRXD PDU unexpected burst length=%zd\n", read_len);
return -EINVAL;
}
burst = (sbit_t *)&buf[8];
bi = (struct trxcon_phyif_burst_ind) {
@ -665,7 +681,7 @@ static int trx_data_rx_cb(struct osmo_fd *ofd, unsigned int what)
.rssi = -(int8_t) buf[5],
.toa256 = (int16_t) (buf[6] << 8) | buf[7],
.burst = burst, /* at least GSM_NBITS_NB_GMSK_BURST */
.burst_len = read_len - TRXDv0_HDR_LEN,
.burst_len = read_len,
};
/* Convert ubits {254..0} to sbits {-127..127} in-place */