From dc24559472a682eb124e869cb110e7a2fd857322 Mon Sep 17 00:00:00 2001 From: Dan Carpenter Date: Fri, 23 Feb 2024 17:20:13 +0300 Subject: lib/stackdepot: off by one in depot_fetch_stack() The stack_pools[] array has DEPOT_MAX_POOLS. The "pools_num" tracks the number of pools which are initialized. See depot_init_pool() for more details. If pool_index == pools_num_cached, this will read one element beyond what we want. If not all the pools are initialized, then the pool will be NULL, triggering a WARN(), and if they are all initialized it will read one element beyond the end of the array. Link: https://lkml.kernel.org/r/361ac881-60b7-471f-91e5-5bf8fe8042b2@moroto.mountain Fixes: b29d31885814 ("lib/stackdepot: store free stack records in a freelist") Signed-off-by: Dan Carpenter Cc: Alexander Potapenko Cc: Andrey Konovalov Signed-off-by: Andrew Morton --- lib/stackdepot.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib/stackdepot.c') diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 8c795bb20afb..af6cc19a2003 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -447,7 +447,7 @@ static struct stack_record *depot_fetch_stack(depot_stack_handle_t handle) lockdep_assert_not_held(&pool_lock); - if (pool_index > pools_num_cached) { + if (pool_index >= pools_num_cached) { WARN(1, "pool index %d out of bounds (%d) for stack id %08x\n", pool_index, pools_num_cached, handle); return NULL; -- cgit v1.2.3