powerpc/cell/OProfile: Fix on-stack array size in activate spu profiling function
The size of the pm_signal_local array should be equal to the
number of SPUs being configured in the array. Currently, the
array is of size 4 (NR_PHYS_CTRS) but being indexed by a for
loop from 0 to 7 (NUM_SPUS_PER_NODE). This could potentially
cause an oops or random memory corruption since the pm_signal_local
array is on the stack. This fixes it.
Signed-off-by: Carl Love <carll@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/arch/powerpc/oprofile/op_model_cell.c b/arch/powerpc/oprofile/op_model_cell.c
index 35141a8..25a4ec2 100644
--- a/arch/powerpc/oprofile/op_model_cell.c
+++ b/arch/powerpc/oprofile/op_model_cell.c
@@ -582,6 +582,13 @@
num_counters = num_ctrs;
+ if (unlikely(num_ctrs > NR_PHYS_CTRS)) {
+ printk(KERN_ERR
+ "%s: Oprofile, number of specified events " \
+ "exceeds number of physical counters\n",
+ __func__);
+ return -EIO;
+ }
pm_regs.group_control = 0;
pm_regs.debug_bus_control = 0;
@@ -830,13 +837,13 @@
static int pm_rtas_activate_spu_profiling(u32 node)
{
int ret, i;
- struct pm_signal pm_signal_local[NR_PHYS_CTRS];
+ struct pm_signal pm_signal_local[NUM_SPUS_PER_NODE];
/*
* Set up the rtas call to configure the debug bus to
* route the SPU PCs. Setup the pm_signal for each SPU
*/
- for (i = 0; i < NUM_SPUS_PER_NODE; i++) {
+ for (i = 0; i < ARRAY_SIZE(pm_signal_local); i++) {
pm_signal_local[i].cpu = node;
pm_signal_local[i].signal_group = 41;
/* spu i on word (i/2) */
@@ -848,7 +855,7 @@
ret = rtas_ibm_cbe_perftools(SUBFUNC_ACTIVATE,
PASSTHRU_ENABLE, pm_signal_local,
- (NUM_SPUS_PER_NODE
+ (ARRAY_SIZE(pm_signal_local)
* sizeof(struct pm_signal)));
if (unlikely(ret)) {