sessiond: fix: possible unaligned access in packed structure

[lttng-tools.git] / src / bin / lttng-sessiond / context.c

diff --git a/src/bin/lttng-sessiond/context.c b/src/bin/lttng-sessiond/context.c
index 9a5738799192a7a26de2cab6e04b361477ac6bd7..8a43cb7c14e9ab5f336f867d8f88df6e7a71cf11 100644 (file)
--- a/src/bin/lttng-sessiond/context.c
+++ b/src/bin/lttng-sessiond/context.c
@@ -34,6 +34,8 @@
 
 /*
  * Add kernel context to all channel.
+ *
+ * Assumes the ownership of kctx.
  */
 static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
                struct ltt_kernel_context *kctx)
@@ -48,9 +50,19 @@ static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
 
        /* Go over all channels */
        cds_list_for_each_entry(kchan, &ksession->channel_list.head, list) {
-               ret = kernel_add_channel_context(kchan, kctx);
-               if (ret < 0) {
-                       ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
+               struct ltt_kernel_context *kctx_copy;
+
+               kctx_copy = trace_kernel_copy_context(kctx);
+               if (!kctx_copy) {
+                       PERROR("zmalloc ltt_kernel_context");
+                       ret = -LTTNG_ERR_NOMEM;
+                       goto error;
+               }
+
+               /* Ownership of kctx_copy is transferred to the callee. */
+               ret = kernel_add_channel_context(kchan, kctx_copy);
+               kctx_copy = NULL;
+               if (ret != 0) {
                        goto error;
                }
        }
@@ -58,11 +70,14 @@ static int add_kctx_all_channels(struct ltt_kernel_session *ksession,
        ret = LTTNG_OK;
 
 error:
+       trace_kernel_destroy_context(kctx);
        return ret;
 }
 
 /*
  * Add kernel context to a specific channel.
+ *
+ * Assumes the ownership of kctx.
  */
 static int add_kctx_to_channel(struct ltt_kernel_context *kctx,
                struct ltt_kernel_channel *kchan)
@@ -74,9 +89,10 @@ static int add_kctx_to_channel(struct ltt_kernel_context *kctx,
 
        DBG("Add kernel context to channel '%s'", kchan->channel->name);
 
+       /* Ownership of kctx is transferred to the callee. */
        ret = kernel_add_channel_context(kchan, kctx);
-       if (ret < 0) {
-               ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
+       kctx = NULL;
+       if (ret != 0) {
                goto error;
        }
 
@@ -91,7 +107,8 @@ error:
  */
 static int add_uctx_to_channel(struct ltt_ust_session *usess,
                enum lttng_domain_type domain,
-               struct ltt_ust_channel *uchan, struct lttng_event_context *ctx)
+               struct ltt_ust_channel *uchan,
+               const struct lttng_event_context *ctx)
 {
        int ret;
        struct ltt_ust_context *uctx = NULL;
@@ -103,7 +120,7 @@ static int add_uctx_to_channel(struct ltt_ust_session *usess,
        /* Check if context is duplicate */
        cds_list_for_each_entry(uctx, &uchan->ctx_list, list) {
                if (trace_ust_match_context(uctx, ctx)) {
-                       ret = -EEXIST;
+                       ret = LTTNG_ERR_UST_CONTEXT_EXIST;
                        goto duplicate;
                }
        }
@@ -124,7 +141,7 @@ static int add_uctx_to_channel(struct ltt_ust_session *usess,
                if (!agt) {
                        agt = agent_create(domain);
                        if (!agt) {
-                               ret = LTTNG_ERR_NOMEM;
+                               ret = -LTTNG_ERR_NOMEM;
                                goto error;
                        }
                        agent_add(agt, usess->agents);
@@ -149,22 +166,23 @@ static int add_uctx_to_channel(struct ltt_ust_session *usess,
        /* Create ltt UST context */
        uctx = trace_ust_create_context(ctx);
        if (uctx == NULL) {
-               ret = -EINVAL;
-               goto error;
-       }
-
-       ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
-       if (ret < 0) {
+               ret = LTTNG_ERR_UST_CONTEXT_INVAL;
                goto error;
        }
 
-       rcu_read_lock();
-
        /* Add ltt UST context node to ltt UST channel */
        lttng_ht_add_ulong(uchan->ctx, &uctx->node);
-       rcu_read_unlock();
        cds_list_add_tail(&uctx->list, &uchan->ctx_list);
 
+       if (!usess->active) {
+               goto end;
+       }
+
+       ret = ust_app_add_ctx_channel_glb(usess, uchan, uctx);
+       if (ret < 0) {
+               goto error;
+       }
+end:
        DBG("Context UST %d added to channel %s", uctx->ctx.ctx, uchan->name);
 
        return 0;
@@ -179,7 +197,7 @@ duplicate:
  * Add kernel context to tracer.
  */
 int context_kernel_add(struct ltt_kernel_session *ksession,
-               struct lttng_event_context *ctx, char *channel_name)
+               const struct lttng_event_context *ctx, char *channel_name)
 {
        int ret;
        struct ltt_kernel_channel *kchan;
@@ -191,7 +209,7 @@ int context_kernel_add(struct ltt_kernel_session *ksession,
 
        kctx = trace_kernel_create_context(NULL);
        if (!kctx) {
-               ret = LTTNG_ERR_NOMEM;
+               ret = -LTTNG_ERR_NOMEM;
                goto error;
        }
 
@@ -231,6 +249,24 @@ int context_kernel_add(struct ltt_kernel_session *ksession,
        case LTTNG_EVENT_CONTEXT_PERF_COUNTER:
                kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PERF_CPU_COUNTER;
                break;
+       case LTTNG_EVENT_CONTEXT_INTERRUPTIBLE:
+               kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_INTERRUPTIBLE;
+               break;
+       case LTTNG_EVENT_CONTEXT_PREEMPTIBLE:
+               kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_PREEMPTIBLE;
+               break;
+       case LTTNG_EVENT_CONTEXT_NEED_RESCHEDULE:
+               kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_NEED_RESCHEDULE;
+               break;
+       case LTTNG_EVENT_CONTEXT_MIGRATABLE:
+               kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_MIGRATABLE;
+               break;
+       case LTTNG_EVENT_CONTEXT_CALLSTACK_KERNEL:
+               kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_CALLSTACK_KERNEL;
+               break;
+       case LTTNG_EVENT_CONTEXT_CALLSTACK_USER:
+               kctx->ctx.ctx = LTTNG_KERNEL_CONTEXT_CALLSTACK_USER;
+               break;
        default:
                ret = LTTNG_ERR_KERN_CONTEXT_FAIL;
                goto error;
@@ -244,6 +280,8 @@ int context_kernel_add(struct ltt_kernel_session *ksession,
 
        if (*channel_name == '\0') {
                ret = add_kctx_all_channels(ksession, kctx);
+               /* Ownership of kctx is transferred to the callee. */
+               kctx = NULL;
                if (ret != LTTNG_OK) {
                        goto error;
                }
@@ -256,12 +294,14 @@ int context_kernel_add(struct ltt_kernel_session *ksession,
                }
 
                ret = add_kctx_to_channel(kctx, kchan);
+               /* Ownership of kctx is transferred to the callee. */
+               kctx = NULL;
                if (ret != LTTNG_OK) {
                        goto error;
                }
        }
 
-       return LTTNG_OK;
+       ret = LTTNG_OK;
 
 error:
        if (kctx) {
@@ -274,7 +314,8 @@ error:
  * Add UST context to tracer.
  */
 int context_ust_add(struct ltt_ust_session *usess,
-               enum lttng_domain_type domain, struct lttng_event_context *ctx,
+               enum lttng_domain_type domain,
+               const struct lttng_event_context *ctx,
                char *channel_name)
 {
        int ret = LTTNG_OK;
@@ -307,7 +348,7 @@ int context_ust_add(struct ltt_ust_session *usess,
                /* Add ctx all events, all channels */
                cds_lfht_for_each_entry(chan_ht->ht, &iter.iter, uchan, node.node) {
                        ret = add_uctx_to_channel(usess, domain, uchan, ctx);
-                       if (ret < 0) {
+                       if (ret) {
                                ERR("Failed to add context to channel %s",
                                                uchan->name);
                                continue;
@@ -317,10 +358,10 @@ int context_ust_add(struct ltt_ust_session *usess,
        }
 
        switch (ret) {
-       case -EEXIST:
-               ret = LTTNG_ERR_UST_CONTEXT_EXIST;
+       case LTTNG_ERR_UST_CONTEXT_EXIST:
                break;
        case -ENOMEM:
+       case -LTTNG_ERR_NOMEM:
                ret = LTTNG_ERR_FATAL;
                break;
        case -EINVAL:
@@ -330,7 +371,11 @@ int context_ust_add(struct ltt_ust_session *usess,
                ret = LTTNG_ERR_UNKNOWN_DOMAIN;
                break;
        default:
-               ret = LTTNG_OK;
+               if (ret != 0 && ret != LTTNG_OK) {
+                       ret = ret > 0 ? ret : LTTNG_ERR_UNK;
+               } else {
+                       ret = LTTNG_OK;
+               }
                break;
        }