stack_depot_save allocates slabs that will be used for storing objects in future.If this slab allocation fails we may get to a situation where space allocation for a new stack_record fails, causing stack_depot_save to return 0 as handle. If user of this handle ends up invoking stack_depot_fetch with this handle value, current implementation of stack_depot_fetch will end up using slab from wrong index. To avoid this check handle value at the beginning.
Signed-off-by: Imran Khan imran.f.khan@oracle.com Suggested-by: Vlastimil Babka vbabka@suse.cz
Acked-by: Vlastimil Babka vbabka@suse.cz --- lib/stackdepot.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/lib/stackdepot.c b/lib/stackdepot.c index 0a2e417f83cb..67439c082490 100644 --- a/lib/stackdepot.c +++ b/lib/stackdepot.c @@ -232,6 +232,9 @@ unsigned int stack_depot_fetch(depot_stack_handle_t handle, struct stack_record *stack;
*entries = NULL; + if (!handle) + return 0; + if (parts.slabindex > depot_index) { WARN(1, "slab index %d out of bounds (%d) for stack id %08x\n", parts.slabindex, depot_index, handle);