[PATCH 2/4] media: vidtv: add error checks

From: Mauro Carvalho Chehab
Date: Thu Oct 01 2020 - 03:27:21 EST


Currently, there are not checks if something gets bad during
memory allocation: it will simply use NULL pointers and
crash.

Add error path at the logic which allocates memory for the
MPEG-TS generator code, propagating the errors up to the
vidtv_bridge. Now, if something wents bad, start_streaming
will return an error that userspace can detect:

ERROR DMX_SET_PES_FILTER failed (PID = 0x2000): 12 Cannot allocate memory

and the driver doesn't crash.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
---
.../media/test-drivers/vidtv/vidtv_bridge.c | 2 +
.../media/test-drivers/vidtv/vidtv_channel.c | 58 +++++++++++++++++--
.../media/test-drivers/vidtv/vidtv_channel.h | 4 +-
drivers/media/test-drivers/vidtv/vidtv_mux.c | 55 +++++++++++++-----
drivers/media/test-drivers/vidtv/vidtv_psi.c | 40 ++++++++++---
.../media/test-drivers/vidtv/vidtv_s302m.c | 14 ++++-
6 files changed, 143 insertions(+), 30 deletions(-)

diff --git a/drivers/media/test-drivers/vidtv/vidtv_bridge.c b/drivers/media/test-drivers/vidtv/vidtv_bridge.c
index fb533c2dd351..b76c1c1ff7c0 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_bridge.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_bridge.c
@@ -181,6 +181,8 @@ static int vidtv_start_streaming(struct vidtv_dvb *dvb)

dvb->streaming = true;
dvb->mux = vidtv_mux_init(dvb->fe[0], dev, mux_args);
+ if (!dvb->mux)
+ return -ENOMEM;
vidtv_mux_start_thread(dvb->mux);

dev_dbg_ratelimited(dev, "Started streaming\n");
diff --git a/drivers/media/test-drivers/vidtv/vidtv_channel.c b/drivers/media/test-drivers/vidtv/vidtv_channel.c
index 28a675a4f367..748697a783a9 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_channel.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_channel.c
@@ -56,43 +56,61 @@ struct vidtv_channel
const u16 s302m_program_pid = 0x101; /* packet id for PMT*/
const u16 s302m_es_pid = 0x111; /* packet id for the ES */
const __be32 s302m_fid = cpu_to_be32(VIDTV_S302M_FORMAT_IDENTIFIER);
-
char *name = ENCODING_ISO8859_15 "Beethoven";
char *provider = ENCODING_ISO8859_15 "LinuxTV.org";

- struct vidtv_channel *s302m = kzalloc(sizeof(*s302m), GFP_KERNEL);
+ struct vidtv_channel *s302m;
struct vidtv_s302m_encoder_init_args encoder_args = {};

+ s302m = kzalloc(sizeof(*s302m), GFP_KERNEL);
+ if (!s302m)
+ return NULL;
+
s302m->name = kstrdup(name, GFP_KERNEL);
+ if (!s302m->name)
+ goto free_s302m;

s302m->service = vidtv_psi_sdt_service_init(NULL, s302m_service_id);
+ if (!s302m->service)
+ goto free_name;

s302m->service->descriptor = (struct vidtv_psi_desc *)
vidtv_psi_service_desc_init(NULL,
DIGITAL_TELEVISION_SERVICE,
name,
provider);
+ if (!s302m->service->descriptor)
+ goto free_service;

s302m->transport_stream_id = transport_stream_id;

s302m->program = vidtv_psi_pat_program_init(NULL,
s302m_service_id,
s302m_program_pid);
+ if (!s302m->program)
+ goto free_service;

s302m->program_num = s302m_program_num;

s302m->streams = vidtv_psi_pmt_stream_init(NULL,
STREAM_PRIVATE_DATA,
s302m_es_pid);
+ if (!s302m->streams)
+ goto free_program;

s302m->streams->descriptor = (struct vidtv_psi_desc *)
vidtv_psi_registration_desc_init(NULL,
s302m_fid,
NULL,
0);
+ if (!s302m->streams->descriptor)
+ goto free_streams;
+
encoder_args.es_pid = s302m_es_pid;

s302m->encoders = vidtv_s302m_encoder_init(encoder_args);
+ if (!s302m->encoders)
+ goto free_streams;

if (head) {
while (head->next)
@@ -102,6 +120,19 @@ struct vidtv_channel
}

return s302m;
+
+free_streams:
+ vidtv_psi_pmt_stream_destroy(s302m->streams);
+free_program:
+ vidtv_psi_pat_program_destroy(s302m->program);
+free_service:
+ vidtv_psi_sdt_service_destroy(s302m->service);
+free_name:
+ kfree(s302m->name);
+free_s302m:
+ kfree(s302m);
+
+ return NULL;
}

static struct vidtv_psi_table_sdt_service
@@ -132,6 +163,8 @@ static struct vidtv_psi_table_sdt_service
tail = vidtv_psi_sdt_service_init(tail, service_id);

desc = vidtv_psi_desc_clone(curr->descriptor);
+ if (!desc)
+ return NULL;
vidtv_psi_desc_assign(&tail->descriptor, desc);

if (!head)
@@ -246,17 +279,25 @@ vidtv_channel_pmt_match_sections(struct vidtv_channel *channels,
}
}

-void vidtv_channel_si_init(struct vidtv_mux *m)
+int vidtv_channel_si_init(struct vidtv_mux *m)
{
struct vidtv_psi_table_pat_program *programs = NULL;
struct vidtv_psi_table_sdt_service *services = NULL;

m->si.pat = vidtv_psi_pat_table_init(m->transport_stream_id);
+ if (!m->si.pat)
+ return -ENOMEM;

m->si.sdt = vidtv_psi_sdt_table_init(m->transport_stream_id);
+ if (!m->si.sdt)
+ return -ENOMEM;

programs = vidtv_channel_pat_prog_cat_into_new(m);
+ if (!programs)
+ return -ENOMEM;
services = vidtv_channel_sdt_serv_cat_into_new(m);
+ if (!services)
+ return -ENOMEM;

/* assemble all programs and assign to PAT */
vidtv_psi_pat_program_assign(m->si.pat, programs);
@@ -265,10 +306,14 @@ void vidtv_channel_si_init(struct vidtv_mux *m)
vidtv_psi_sdt_service_assign(m->si.sdt, services);

m->si.pmt_secs = vidtv_psi_pmt_create_sec_for_each_pat_entry(m->si.pat, m->pcr_pid);
+ if (!m->si.pmt_secs)
+ return -ENOMEM;

vidtv_channel_pmt_match_sections(m->channels,
m->si.pmt_secs,
m->si.pat->programs);
+
+ return 0;
}

void vidtv_channel_si_destroy(struct vidtv_mux *m)
@@ -285,10 +330,15 @@ void vidtv_channel_si_destroy(struct vidtv_mux *m)
vidtv_psi_sdt_table_destroy(m->si.sdt);
}

-void vidtv_channels_init(struct vidtv_mux *m)
+int vidtv_channels_init(struct vidtv_mux *m)
{
/* this is the place to add new 'channels' for vidtv */
m->channels = vidtv_channel_s302m_init(NULL, m->transport_stream_id);
+
+ if (!m->channels)
+ return -ENOMEM;
+
+ return 0;
}

void vidtv_channels_destroy(struct vidtv_mux *m)
diff --git a/drivers/media/test-drivers/vidtv/vidtv_channel.h b/drivers/media/test-drivers/vidtv/vidtv_channel.h
index 93a436a27824..d9a0f6fbfd92 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_channel.h
+++ b/drivers/media/test-drivers/vidtv/vidtv_channel.h
@@ -62,14 +62,14 @@ struct vidtv_channel {
* vidtv_channel_si_init - Init the PSI tables from the channels in the mux
* @m: The mux containing the channels.
*/
-void vidtv_channel_si_init(struct vidtv_mux *m);
+int vidtv_channel_si_init(struct vidtv_mux *m);
void vidtv_channel_si_destroy(struct vidtv_mux *m);

/**
* vidtv_channels_init - Init hardcoded, fake 'channels'.
* @m: The mux to store the channels into.
*/
-void vidtv_channels_init(struct vidtv_mux *m);
+int vidtv_channels_init(struct vidtv_mux *m);
struct vidtv_channel
*vidtv_channel_s302m_init(struct vidtv_channel *head, u16 transport_stream_id);
void vidtv_channels_destroy(struct vidtv_mux *m);
diff --git a/drivers/media/test-drivers/vidtv/vidtv_mux.c b/drivers/media/test-drivers/vidtv/vidtv_mux.c
index b7223f3a2c9d..9086edd45252 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_mux.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_mux.c
@@ -47,33 +47,38 @@ static struct vidtv_mux_pid_ctx
struct vidtv_mux_pid_ctx *ctx;

ctx = vidtv_mux_get_pid_ctx(m, pid);
-
if (ctx)
- goto end;
+ return ctx;
+
+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+ if (!ctx)
+ return NULL;

- ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
ctx->pid = pid;
ctx->cc = 0;
hash_add(m->pid_ctx, &ctx->h, pid);

-end:
return ctx;
}

-static void vidtv_mux_pid_ctx_init(struct vidtv_mux *m)
+static int vidtv_mux_pid_ctx_init(struct vidtv_mux *m)
{
struct vidtv_psi_table_pat_program *p = m->si.pat->program;
u16 pid;

hash_init(m->pid_ctx);
/* push the pcr pid ctx */
- vidtv_mux_create_pid_ctx_once(m, m->pcr_pid);
- /* push the null packet pid ctx */
- vidtv_mux_create_pid_ctx_once(m, TS_NULL_PACKET_PID);
+ if (!vidtv_mux_create_pid_ctx_once(m, m->pcr_pid))
+ return -ENOMEM;
+ /* push the NULL packet pid ctx */
+ if (!vidtv_mux_create_pid_ctx_once(m, TS_NULL_PACKET_PID))
+ return -ENOMEM;
/* push the PAT pid ctx */
- vidtv_mux_create_pid_ctx_once(m, VIDTV_PAT_PID);
+ if (!vidtv_mux_create_pid_ctx_once(m, VIDTV_PAT_PID))
+ return -ENOMEM;
/* push the SDT pid ctx */
- vidtv_mux_create_pid_ctx_once(m, VIDTV_SDT_PID);
+ if (!vidtv_mux_create_pid_ctx_once(m, VIDTV_SDT_PID))
+ return -ENOMEM;

/* add a ctx for all PMT sections */
while (p) {
@@ -81,6 +86,8 @@ static void vidtv_mux_pid_ctx_init(struct vidtv_mux *m)
vidtv_mux_create_pid_ctx_once(m, pid);
p = p->next;
}
+
+ return 0;
}

static void vidtv_mux_pid_ctx_destroy(struct vidtv_mux *m)
@@ -429,7 +436,11 @@ struct vidtv_mux *vidtv_mux_init(struct dvb_frontend *fe,
struct device *dev,
struct vidtv_mux_init_args args)
{
- struct vidtv_mux *m = kzalloc(sizeof(*m), GFP_KERNEL);
+ struct vidtv_mux *m;
+
+ m = kzalloc(sizeof(*m), GFP_KERNEL);
+ if (!m)
+ return NULL;

m->dev = dev;
m->fe = fe;
@@ -441,6 +452,9 @@ struct vidtv_mux *vidtv_mux_init(struct dvb_frontend *fe,
m->on_new_packets_available_cb = args.on_new_packets_available_cb;

m->mux_buf = vzalloc(args.mux_buf_sz);
+ if (!m->mux_buf)
+ goto free_mux;
+
m->mux_buf_sz = args.mux_buf_sz;

m->pcr_pid = args.pcr_pid;
@@ -451,16 +465,29 @@ struct vidtv_mux *vidtv_mux_init(struct dvb_frontend *fe,
if (args.channels)
m->channels = args.channels;
else
- vidtv_channels_init(m);
+ if (vidtv_channels_init(m) < 0)
+ goto free_mux_buf;

/* will alloc data for pmt_sections after initializing pat */
- vidtv_channel_si_init(m);
+ if (vidtv_channel_si_init(m) < 0)
+ goto free_channels;

INIT_WORK(&m->mpeg_thread, vidtv_mux_tick);

- vidtv_mux_pid_ctx_init(m);
+ if (vidtv_mux_pid_ctx_init(m) < 0)
+ goto free_channel_si;

return m;
+
+free_channel_si:
+ vidtv_channel_si_destroy(m);
+free_channels:
+ vidtv_channels_destroy(m);
+free_mux_buf:
+ vfree(m->mux_buf);
+free_mux:
+ kfree(m);
+ return NULL;
}

void vidtv_mux_destroy(struct vidtv_mux *m)
diff --git a/drivers/media/test-drivers/vidtv/vidtv_psi.c b/drivers/media/test-drivers/vidtv/vidtv_psi.c
index 0e58cbc79fb2..3151b300a91b 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_psi.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_psi.c
@@ -325,6 +325,8 @@ struct vidtv_psi_desc_service *vidtv_psi_service_desc_init(struct vidtv_psi_desc
u32 provider_name_len = provider_name ? strlen(provider_name) : 0;

desc = kzalloc(sizeof(*desc), GFP_KERNEL);
+ if (!desc)
+ return NULL;

desc->type = SERVICE_DESCRIPTOR;

@@ -364,6 +366,8 @@ struct vidtv_psi_desc_registration
struct vidtv_psi_desc_registration *desc;

desc = kzalloc(sizeof(*desc) + sizeof(format_id) + additional_info_len, GFP_KERNEL);
+ if (!desc)
+ return NULL;

desc->type = REGISTRATION_DESCRIPTOR;

@@ -410,11 +414,12 @@ struct vidtv_psi_desc *vidtv_psi_desc_clone(struct vidtv_psi_desc *desc)
default:
curr = kzalloc(sizeof(*desc) + desc->length, GFP_KERNEL);
memcpy(curr, desc, sizeof(*desc) + desc->length);
- break;
- }
+ }

- if (curr)
- curr->next = NULL;
+ if (!curr)
+ return NULL;
+
+ curr->next = NULL;
if (!head)
head = curr;
if (prev)
@@ -693,6 +698,8 @@ vidtv_psi_pat_program_init(struct vidtv_psi_table_pat_program *head,
const u16 RESERVED = 0x07;

program = kzalloc(sizeof(*program), GFP_KERNEL);
+ if (!program)
+ return NULL;

program->service_id = cpu_to_be16(service_id);

@@ -754,11 +761,15 @@ vidtv_psi_pat_program_assign(struct vidtv_psi_table_pat *pat,

struct vidtv_psi_table_pat *vidtv_psi_pat_table_init(u16 transport_stream_id)
{
- struct vidtv_psi_table_pat *pat = kzalloc(sizeof(*pat), GFP_KERNEL);
+ struct vidtv_psi_table_pat *pat;
const u16 SYNTAX = 0x1;
const u16 ZERO = 0x0;
const u16 ONES = 0x03;

+ pat = kzalloc(sizeof(*pat), GFP_KERNEL);
+ if (!pat)
+ return NULL;
+
pat->header.table_id = 0x0;

pat->header.bitfield = cpu_to_be16((SYNTAX << 15) | (ZERO << 14) | (ONES << 12));
@@ -858,6 +869,8 @@ vidtv_psi_pmt_stream_init(struct vidtv_psi_table_pmt_stream *head,
u16 desc_loop_len;

stream = kzalloc(sizeof(*stream), GFP_KERNEL);
+ if (!stream)
+ return NULL;

stream->type = stream_type;

@@ -932,7 +945,7 @@ u16 vidtv_psi_pmt_get_pid(struct vidtv_psi_table_pmt *section,
struct vidtv_psi_table_pmt *vidtv_psi_pmt_table_init(u16 program_number,
u16 pcr_pid)
{
- struct vidtv_psi_table_pmt *pmt = kzalloc(sizeof(*pmt), GFP_KERNEL);
+ struct vidtv_psi_table_pmt *pmt;
const u16 SYNTAX = 0x1;
const u16 ZERO = 0x0;
const u16 ONES = 0x03;
@@ -940,6 +953,10 @@ struct vidtv_psi_table_pmt *vidtv_psi_pmt_table_init(u16 program_number,
const u16 RESERVED2 = 0x0f;
u16 desc_loop_len;

+ pmt = kzalloc(sizeof(*pmt), GFP_KERNEL);
+ if (!pmt)
+ return NULL;
+
if (!pcr_pid)
pcr_pid = 0x1fff;

@@ -1079,14 +1096,17 @@ void vidtv_psi_pmt_table_destroy(struct vidtv_psi_table_pmt *pmt)

struct vidtv_psi_table_sdt *vidtv_psi_sdt_table_init(u16 transport_stream_id)
{
- struct vidtv_psi_table_sdt *sdt = kzalloc(sizeof(*sdt), GFP_KERNEL);
+ struct vidtv_psi_table_sdt *sdt;
const u16 SYNTAX = 0x1;
const u16 ONE = 0x1;
const u16 ONES = 0x03;
const u16 RESERVED = 0xff;

+ sdt = kzalloc(sizeof(*sdt), GFP_KERNEL);
+ if (!sdt)
+ return NULL;
+
sdt->header.table_id = 0x42;
-
sdt->header.bitfield = cpu_to_be16((SYNTAX << 15) | (ONE << 14) | (ONES << 12));

/*
@@ -1219,6 +1239,8 @@ struct vidtv_psi_table_sdt_service
struct vidtv_psi_table_sdt_service *service;

service = kzalloc(sizeof(*service), GFP_KERNEL);
+ if (!service)
+ return NULL;

/*
* ETSI 300 468: this is a 16bit field which serves as a label to
@@ -1292,6 +1314,8 @@ vidtv_psi_pmt_create_sec_for_each_pat_entry(struct vidtv_psi_table_pat *pat, u16
pmt_secs = kcalloc(pat->programs,
sizeof(struct vidtv_psi_table_pmt *),
GFP_KERNEL);
+ if (!pmt_secs)
+ return NULL;

while (program) {
pmt_secs[i] = vidtv_psi_pmt_table_init(be16_to_cpu(program->service_id), pcr_pid);
diff --git a/drivers/media/test-drivers/vidtv/vidtv_s302m.c b/drivers/media/test-drivers/vidtv/vidtv_s302m.c
index 95c5b7bfd491..6e5e72ce90d0 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_s302m.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.c
@@ -144,7 +144,11 @@ static const struct tone_duration beethoven_5th_symphony[] = {

static struct vidtv_access_unit *vidtv_s302m_access_unit_init(struct vidtv_access_unit *head)
{
- struct vidtv_access_unit *au = kzalloc(sizeof(*au), GFP_KERNEL);
+ struct vidtv_access_unit *au;
+
+ au = kzalloc(sizeof(*au), GFP_KERNEL);
+ if (!au)
+ return NULL;

if (head) {
while (head->next)
@@ -439,9 +443,13 @@ static u32 vidtv_s302m_clear(struct vidtv_encoder *e)
struct vidtv_encoder
*vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args)
{
- struct vidtv_encoder *e = kzalloc(sizeof(*e), GFP_KERNEL);
+ struct vidtv_encoder *e;
u32 priv_sz = sizeof(struct vidtv_s302m_ctx);

+ e = kzalloc(sizeof(*e), GFP_KERNEL);
+ if (!e)
+ return NULL;
+
e->id = S302M;

if (args.name)
@@ -460,6 +468,8 @@ struct vidtv_encoder

e->is_video_encoder = false;
e->ctx = kzalloc(priv_sz, GFP_KERNEL);
+ if (!e->ctx)
+ return NULL;

e->encode = vidtv_s302m_encode;
e->clear = vidtv_s302m_clear;
--
2.26.2