selftests/bpf: Add test cases for inner map
Add test cases to test the race between the destroy of inner map due to map-in-map update and the access of inner map in bpf program. The following 4 combinations are added: (1) array map in map array + bpf program (2) array map in map array + sleepable bpf program (3) array map in map htab + bpf program (4) array map in map htab + sleepable bpf program Before applying the fixes, when running `./test_prog -a map_in_map`, the following error was reported: ================================================================== BUG: KASAN: slab-use-after-free in array_map_update_elem+0x48/0x3e0 Read of size 4 at addr ffff888114f33824 by task test_progs/1858 CPU: 1 PID: 1858 Comm: test_progs Tainted: G O 6.6.0+ #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ...... Call Trace: <TASK> dump_stack_lvl+0x4a/0x90 print_report+0xd2/0x620 kasan_report+0xd1/0x110 __asan_load4+0x81/0xa0 array_map_update_elem+0x48/0x3e0 bpf_prog_be94a9f26772f5b7_access_map_in_array+0xe6/0xf6 trace_call_bpf+0x1aa/0x580 kprobe_perf_func+0xdd/0x430 kprobe_dispatcher+0xa0/0xb0 kprobe_ftrace_handler+0x18b/0x2e0 0xffffffffc02280f7 RIP: 0010:__x64_sys_getpgid+0x1/0x30 ...... </TASK> Allocated by task 1857: kasan_save_stack+0x26/0x50 kasan_set_track+0x25/0x40 kasan_save_alloc_info+0x1e/0x30 __kasan_kmalloc+0x98/0xa0 __kmalloc_node+0x6a/0x150 __bpf_map_area_alloc+0x141/0x170 bpf_map_area_alloc+0x10/0x20 array_map_alloc+0x11f/0x310 map_create+0x28a/0xb40 __sys_bpf+0x753/0x37c0 __x64_sys_bpf+0x44/0x60 do_syscall_64+0x36/0xb0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 Freed by task 11: kasan_save_stack+0x26/0x50 kasan_set_track+0x25/0x40 kasan_save_free_info+0x2b/0x50 __kasan_slab_free+0x113/0x190 slab_free_freelist_hook+0xd7/0x1e0 __kmem_cache_free+0x170/0x260 kfree+0x9b/0x160 kvfree+0x2d/0x40 bpf_map_area_free+0xe/0x20 array_map_free+0x120/0x2c0 bpf_map_free_deferred+0xd7/0x1e0 process_one_work+0x462/0x990 worker_thread+0x370/0x670 kthread+0x1b0/0x200 ret_from_fork+0x3a/0x70 ret_from_fork_asm+0x1b/0x30 Last potentially related work creation: kasan_save_stack+0x26/0x50 __kasan_record_aux_stack+0x94/0xb0 kasan_record_aux_stack_noalloc+0xb/0x20 __queue_work+0x331/0x950 queue_work_on+0x75/0x80 bpf_map_put+0xfa/0x160 bpf_map_fd_put_ptr+0xe/0x20 bpf_fd_array_map_update_elem+0x174/0x1b0 bpf_map_update_value+0x2b7/0x4a0 __sys_bpf+0x2551/0x37c0 __x64_sys_bpf+0x44/0x60 do_syscall_64+0x36/0xb0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 Signed-off-by:Hou Tao <houtao1@huawei.com> Link: https://lore.kernel.org/r/20231204140425.1480317-7-houtao@huaweicloud.com Signed-off-by:
Alexei Starovoitov <ast@kernel.org>
parent
af66bfd3
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