tracing/trivial: Use kcalloc instead of kzalloc to allocate array

The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.

The semantic patch that makes this change is available
in https://lkml.org/lkml/2011/11/25/107

Link: http://lkml.kernel.org/r/1322600880.1534.347.camel@localhost.localdomain
Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index e2e0597c0845b2dd763c79854461a2f20ae75457..d1499e910fe8ca67f266421da269d32f17a950b3 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1129,7 +1129,7 @@ static struct ftrace_hash *alloc_ftrace_hash(int size_bits)
                return NULL;
 
        size = 1 << size_bits;
-       hash->buckets = kzalloc(sizeof(*hash->buckets) * size, GFP_KERNEL);
+       hash->buckets = kcalloc(size, sizeof(*hash->buckets), GFP_KERNEL);
 
        if (!hash->buckets) {
                kfree(hash);

diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 24aee71274518c6e98867b4b5c008ed6070919d7..76afaee99dbc141704db3d4acdec1569ddc4995a 100644 (file)
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -685,7 +685,7 @@ find_event_field(struct ftrace_event_call *call, char *name)
 
 static int __alloc_pred_stack(struct pred_stack *stack, int n_preds)
 {
-       stack->preds = kzalloc(sizeof(*stack->preds)*(n_preds + 1), GFP_KERNEL);
+       stack->preds = kcalloc(n_preds + 1, sizeof(*stack->preds), GFP_KERNEL);
        if (!stack->preds)
                return -ENOMEM;
        stack->index = n_preds;
@@ -826,8 +826,7 @@ static int __alloc_preds(struct event_filter *filter, int n_preds)
        if (filter->preds)
                __free_preds(filter);
 
-       filter->preds =
-               kzalloc(sizeof(*filter->preds) * n_preds, GFP_KERNEL);
+       filter->preds = kcalloc(n_preds, sizeof(*filter->preds), GFP_KERNEL);
 
        if (!filter->preds)
                return -ENOMEM;
@@ -1486,7 +1485,7 @@ static int fold_pred(struct filter_pred *preds, struct filter_pred *root)
        children = count_leafs(preds, &preds[root->left]);
        children += count_leafs(preds, &preds[root->right]);
 
-       root->ops = kzalloc(sizeof(*root->ops) * children, GFP_KERNEL);
+       root->ops = kcalloc(children, sizeof(*root->ops), GFP_KERNEL);
        if (!root->ops)
                return -ENOMEM;
 

diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index cb654542c1a1621fc325cba70699f8b2d1be9658..43500153dd1ea5f588413497133f6928ecde6091 100644 (file)
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -468,8 +468,8 @@ int __init init_ftrace_syscalls(void)
        unsigned long addr;
        int i;
 
-       syscalls_metadata = kzalloc(sizeof(*syscalls_metadata) *
-                                       NR_syscalls, GFP_KERNEL);
+       syscalls_metadata = kcalloc(NR_syscalls, sizeof(*syscalls_metadata),
+                                   GFP_KERNEL);
        if (!syscalls_metadata) {
                WARN_ON(1);
                return -ENOMEM;