[ Upstream commit 860b7d2286236170a36f94946d03ca9888d32571 ]
The data structure (i.e struct imc_mem_info) to hold the memory address information for nest imc units is allocated based on the number of nodes in the system.
nest_imc_event_init() traverse this struct array to calculate the memory base address for the event-cpu. If we fail to find a match for the event cpu's chip-id in imc_mem_info struct array, then the do-while loop will iterate until we crash.
Fix this by changing the loop exit condition based on the number of non zero vbase elements in the array, since the allocation is done for nr_chips + 1.
Reported-by: Dan Carpenter dan.carpenter@oracle.com Fixes: 885dcd709ba91 ("powerpc/perf: Add nest IMC PMU support") Signed-off-by: Anju T Sudhakar anju@linux.vnet.ibm.com Reviewed-by: Madhavan Srinivasan maddy@linux.vnet.ibm.com Signed-off-by: Michael Ellerman mpe@ellerman.id.au Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/perf/imc-pmu.c | 2 +- arch/powerpc/platforms/powernv/opal-imc.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/arch/powerpc/perf/imc-pmu.c b/arch/powerpc/perf/imc-pmu.c index 6159e9edddfd0..2d12f0037e3a5 100644 --- a/arch/powerpc/perf/imc-pmu.c +++ b/arch/powerpc/perf/imc-pmu.c @@ -499,7 +499,7 @@ static int nest_imc_event_init(struct perf_event *event) break; } pcni++; - } while (pcni); + } while (pcni->vbase != 0);
if (!flag) return -ENODEV; diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c index 58a07948c76e7..3d27f02695e41 100644 --- a/arch/powerpc/platforms/powernv/opal-imc.c +++ b/arch/powerpc/platforms/powernv/opal-imc.c @@ -127,7 +127,7 @@ static int imc_get_mem_addr_nest(struct device_node *node, nr_chips)) goto error;
- pmu_ptr->mem_info = kcalloc(nr_chips, sizeof(*pmu_ptr->mem_info), + pmu_ptr->mem_info = kcalloc(nr_chips + 1, sizeof(*pmu_ptr->mem_info), GFP_KERNEL); if (!pmu_ptr->mem_info) goto error;