Commit 55a24d92 authored by David Carlier's avatar David Carlier Committed by Tejun Heo
Browse files

tools/sched_ext: scx_central: fix CPU_SET and skeleton leak on early exit 



Use CPU_SET_S() instead of CPU_SET() on the dynamically allocated
cpuset to avoid a potential out-of-bounds write when nr_cpu_ids
exceeds CPU_SETSIZE.

Also destroy the skeleton before returning on invalid central CPU ID
to prevent a resource leak.

Signed-off-by: default avatarDavid Carlier <devnexen@gmail.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent 07676846

tools/sched_ext/scx_central.c

+2 −1
Original line number Diff line number Diff line
@@ -74,6 +74,7 @@ int main(int argc, char **argv) 
			u32 central_cpu = strtoul(optarg, NULL, 0);

			if (central_cpu >= skel->rodata->nr_cpu_ids) {

				fprintf(stderr, "invalid central CPU id value, %u given (%u max)\n", central_cpu, skel->rodata->nr_cpu_ids);

				scx_central__destroy(skel);

				return -1;

			}

			skel->rodata->central_cpu = (s32)central_cpu;
@@ -109,7 +110,7 @@ int main(int argc, char **argv) 
	SCX_BUG_ON(!cpuset, "Failed to allocate cpuset");

	cpuset_size = CPU_ALLOC_SIZE(skel->rodata->nr_cpu_ids);

	CPU_ZERO_S(cpuset_size, cpuset);

	CPU_SET(skel->rodata->central_cpu, cpuset);

	CPU_SET_S(skel->rodata->central_cpu, cpuset_size, cpuset);

	SCX_BUG_ON(sched_setaffinity(0, cpuset_size, cpuset),

		   "Failed to affinitize to central CPU %d (max %d)",

		   skel->rodata->central_cpu, skel->rodata->nr_cpu_ids - 1);