Fix: use after free in ring buffer clients

[lttng-modules.git] / lttng-abi.c

diff --git a/lttng-abi.c b/lttng-abi.c
index 1cc9510110dbc216ecf02c4ca8157dfc8f12a78e..261a0ad3f8a1bf0ae4af6e76c9a2a246115589b4 100644 (file)
--- a/lttng-abi.c
+++ b/lttng-abi.c
@@ -1347,7 +1347,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        struct lib_ring_buffer *buf = filp->private_data;
        struct channel *chan = buf->backend.chan;
        const struct lib_ring_buffer_config *config = &chan->backend.config;
-       struct lttng_channel *lttng_chan = channel_get_private(chan);
+       const struct lttng_channel_ops *ops = chan->backend.priv_ops;
        int ret;
 
        if (atomic_read(&chan->record_disabled))
@@ -1358,9 +1358,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        {
                uint64_t ts;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->timestamp_begin(config, buf, &ts);
+               ret = ops->timestamp_begin(config, buf, &ts);
                if (ret < 0)
                        goto error;
                return put_u64(ts, arg);
@@ -1369,9 +1367,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        {
                uint64_t ts;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->timestamp_end(config, buf, &ts);
+               ret = ops->timestamp_end(config, buf, &ts);
                if (ret < 0)
                        goto error;
                return put_u64(ts, arg);
@@ -1380,9 +1376,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        {
                uint64_t ed;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->events_discarded(config, buf, &ed);
+               ret = ops->events_discarded(config, buf, &ed);
                if (ret < 0)
                        goto error;
                return put_u64(ed, arg);
@@ -1391,9 +1385,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        {
                uint64_t cs;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->content_size(config, buf, &cs);
+               ret = ops->content_size(config, buf, &cs);
                if (ret < 0)
                        goto error;
                return put_u64(cs, arg);
@@ -1402,9 +1394,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        {
                uint64_t ps;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->packet_size(config, buf, &ps);
+               ret = ops->packet_size(config, buf, &ps);
                if (ret < 0)
                        goto error;
                return put_u64(ps, arg);
@@ -1413,9 +1403,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        {
                uint64_t si;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->stream_id(config, buf, &si);
+               ret = ops->stream_id(config, buf, &si);
                if (ret < 0)
                        goto error;
                return put_u64(si, arg);
@@ -1424,9 +1412,7 @@ static long lttng_stream_ring_buffer_ioctl(struct file *filp,
        {
                uint64_t ts;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->current_timestamp(config, buf, &ts);
+               ret = ops->current_timestamp(config, buf, &ts);
                if (ret < 0)
                        goto error;
                return put_u64(ts, arg);
@@ -1447,7 +1433,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        struct lib_ring_buffer *buf = filp->private_data;
        struct channel *chan = buf->backend.chan;
        const struct lib_ring_buffer_config *config = &chan->backend.config;
-       struct lttng_channel *lttng_chan = channel_get_private(chan);
+       const struct lttng_channel_ops *ops = chan->backend.priv_ops;
        int ret;
 
        if (atomic_read(&chan->record_disabled))
@@ -1458,9 +1444,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        {
                uint64_t ts;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->timestamp_begin(config, buf, &ts);
+               ret = ops->timestamp_begin(config, buf, &ts);
                if (ret < 0)
                        goto error;
                return put_u64(ts, arg);
@@ -1469,9 +1453,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        {
                uint64_t ts;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->timestamp_end(config, buf, &ts);
+               ret = ops->timestamp_end(config, buf, &ts);
                if (ret < 0)
                        goto error;
                return put_u64(ts, arg);
@@ -1480,9 +1462,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        {
                uint64_t ed;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->events_discarded(config, buf, &ed);
+               ret = ops->events_discarded(config, buf, &ed);
                if (ret < 0)
                        goto error;
                return put_u64(ed, arg);
@@ -1491,9 +1471,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        {
                uint64_t cs;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->content_size(config, buf, &cs);
+               ret = ops->content_size(config, buf, &cs);
                if (ret < 0)
                        goto error;
                return put_u64(cs, arg);
@@ -1502,9 +1480,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        {
                uint64_t ps;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->packet_size(config, buf, &ps);
+               ret = ops->packet_size(config, buf, &ps);
                if (ret < 0)
                        goto error;
                return put_u64(ps, arg);
@@ -1513,9 +1489,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        {
                uint64_t si;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->stream_id(config, buf, &si);
+               ret = ops->stream_id(config, buf, &si);
                if (ret < 0)
                        goto error;
                return put_u64(si, arg);
@@ -1524,9 +1498,7 @@ static long lttng_stream_ring_buffer_compat_ioctl(struct file *filp,
        {
                uint64_t ts;
 
-               if (!lttng_chan->ops)
-                       goto error;
-               ret = lttng_chan->ops->current_timestamp(config, buf, &ts);
+               ret = ops->current_timestamp(config, buf, &ts);
                if (ret < 0)
                        goto error;
                return put_u64(ts, arg);