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media: dvb_net: ensure that dvb_net_ule_handle is fully initialized

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commit efb9ab6725 ("[media] dvb_net: prepare to split a very
complex function") changed the ULE handling logic, simplifying it.
However, it forgot to keep the initialization for .priv and to
zero .ule_hist fields.

The lack of .priv cause crashes if dvb_net_ule() is called, as
the function assuems that .priv field to be initialized.

With regards to .ule_hist, the current logic is broken and don't
even compile if ULE_DEBUG. Fix it by making the debug vars static
again, and be sure to pass iov parameter to dvb_net_ule_check_crc().

Fixes: efb9ab6725 ("[media] dvb_net: prepare to split a very complex function")

Suggested-by: Ron Economos <w6rz@comcast.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Mauro Carvalho Chehab 2017-12-11 11:37:24 -05:00
parent 8ea636dcec
commit b93a25e120
1 changed files with 27 additions and 29 deletions
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56
drivers/media/dvb-core/dvb_net.c
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@ -82,6 +82,13 @@ static inline __u32 iov_crc32( __u32 c, struct kvec *iov, unsigned int cnt )
#ifdef ULE_DEBUG
/*
* The code inside ULE_DEBUG keeps a history of the
* last 100 TS cells processed.
*/
static unsigned char ule_hist[100*TS_SZ] = { 0 };
static unsigned char *ule_where = ule_hist, ule_dump;
static void hexdump(const unsigned char *buf, unsigned short len)
{
print_hex_dump_debug("", DUMP_PREFIX_OFFSET, 16, 1, buf, len, true);
@ -320,14 +327,6 @@ struct dvb_net_ule_handle {
const u8 *ts, *ts_end, *from_where;
u8 ts_remain, how_much, new_ts;
bool error;
#ifdef ULE_DEBUG
/*
* The code inside ULE_DEBUG keeps a history of the
* last 100 TS cells processed.
*/
static unsigned char ule_hist[100*TS_SZ];
static unsigned char *ule_where = ule_hist, ule_dump;
#endif
};
static int dvb_net_ule_new_ts_cell(struct dvb_net_ule_handle *h)
@ -335,14 +334,14 @@ static int dvb_net_ule_new_ts_cell(struct dvb_net_ule_handle *h)
/* We are about to process a new TS cell. */
#ifdef ULE_DEBUG
if (h->ule_where >= &h->ule_hist[100*TS_SZ])
h->ule_where = h->ule_hist;
memcpy(h->ule_where, h->ts, TS_SZ);
if (h->ule_dump) {
hexdump(h->ule_where, TS_SZ);
h->ule_dump = 0;
if (ule_where >= &ule_hist[100*TS_SZ])
ule_where = ule_hist;
memcpy(ule_where, h->ts, TS_SZ);
if (ule_dump) {
hexdump(ule_where, TS_SZ);
ule_dump = 0;
}
h->ule_where += TS_SZ;
ule_where += TS_SZ;
#endif
/*
@ -660,6 +659,7 @@ static int dvb_net_ule_should_drop(struct dvb_net_ule_handle *h)
static void dvb_net_ule_check_crc(struct dvb_net_ule_handle *h,
struct kvec iov[3],
u32 ule_crc, u32 expected_crc)
{
u8 dest_addr[ETH_ALEN];
@ -677,17 +677,17 @@ static void dvb_net_ule_check_crc(struct dvb_net_ule_handle *h,
hexdump(iov[1].iov_base, iov[1].iov_len);
hexdump(iov[2].iov_base, iov[2].iov_len);
if (h->ule_where == h->ule_hist) {
hexdump(&h->ule_hist[98*TS_SZ], TS_SZ);
hexdump(&h->ule_hist[99*TS_SZ], TS_SZ);
} else if (h->ule_where == &h->ule_hist[TS_SZ]) {
hexdump(&h->ule_hist[99*TS_SZ], TS_SZ);
hexdump(h->ule_hist, TS_SZ);
if (ule_where == ule_hist) {
hexdump(&ule_hist[98*TS_SZ], TS_SZ);
hexdump(&ule_hist[99*TS_SZ], TS_SZ);
} else if (ule_where == &ule_hist[TS_SZ]) {
hexdump(&ule_hist[99*TS_SZ], TS_SZ);
hexdump(ule_hist, TS_SZ);
} else {
hexdump(h->ule_where - TS_SZ - TS_SZ, TS_SZ);
hexdump(h->ule_where - TS_SZ, TS_SZ);
hexdump(ule_where - TS_SZ - TS_SZ, TS_SZ);
hexdump(ule_where - TS_SZ, TS_SZ);
}
h->ule_dump = 1;
ule_dump = 1;
#endif
h->dev->stats.rx_errors++;
@ -779,6 +779,8 @@ static void dvb_net_ule(struct net_device *dev, const u8 *buf, size_t buf_len)
int ret;
struct dvb_net_ule_handle h = {
.dev = dev,
.priv = netdev_priv(dev),
.ethh = NULL,
.buf = buf,
.buf_len = buf_len,
.skipped = 0L,
@ -788,11 +790,7 @@ static void dvb_net_ule(struct net_device *dev, const u8 *buf, size_t buf_len)
.ts_remain = 0,
.how_much = 0,
.new_ts = 1,
.ethh = NULL,
.error = false,
#ifdef ULE_DEBUG
.ule_where = ule_hist,
#endif
};
/*
@ -860,7 +858,7 @@ static void dvb_net_ule(struct net_device *dev, const u8 *buf, size_t buf_len)
*(tail - 2) << 8 |
*(tail - 1);
dvb_net_ule_check_crc(&h, ule_crc, expected_crc);
dvb_net_ule_check_crc(&h, iov, ule_crc, expected_crc);
/* Prepare for next SNDU. */
reset_ule(h.priv);