From: Song Liu songliubraving@fb.com
[ Upstream commit 7ac6ad051150592557520b45773201b987ecfce3 ]
syzbot reported a WARNING for allocating too big memory:
WARNING: CPU: 1 PID: 8484 at mm/page_alloc.c:4976 __alloc_pages_nodemask+0x5f8/0x730 mm/page_alloc.c:5011 Modules linked in: CPU: 1 PID: 8484 Comm: syz-executor862 Not tainted 5.11.0-rc2-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__alloc_pages_nodemask+0x5f8/0x730 mm/page_alloc.c:4976 Code: 00 00 0c 00 0f 85 a7 00 00 00 8b 3c 24 4c 89 f2 44 89 e6 c6 44 24 70 00 48 89 6c 24 58 e8 d0 d7 ff ff 49 89 c5 e9 ea fc ff ff <0f> 0b e9 b5 fd ff ff 89 74 24 14 4c 89 4c 24 08 4c 89 74 24 18 e8 RSP: 0018:ffffc900012efb10 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 1ffff9200025df66 RCX: 0000000000000000 RDX: 0000000000000000 RSI: dffffc0000000000 RDI: 0000000000140dc0 RBP: 0000000000140dc0 R08: 0000000000000000 R09: 0000000000000000 R10: ffffffff81b1f7e1 R11: 0000000000000000 R12: 0000000000000014 R13: 0000000000000014 R14: 0000000000000000 R15: 0000000000000000 FS: 000000000190c880(0000) GS:ffff8880b9e00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f08b7f316c0 CR3: 0000000012073000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: alloc_pages_current+0x18c/0x2a0 mm/mempolicy.c:2267 alloc_pages include/linux/gfp.h:547 [inline] kmalloc_order+0x2e/0xb0 mm/slab_common.c:837 kmalloc_order_trace+0x14/0x120 mm/slab_common.c:853 kmalloc include/linux/slab.h:557 [inline] kzalloc include/linux/slab.h:682 [inline] bpf_prog_test_run_raw_tp+0x4b5/0x670 net/bpf/test_run.c:282 bpf_prog_test_run kernel/bpf/syscall.c:3120 [inline] __do_sys_bpf+0x1ea9/0x4f10 kernel/bpf/syscall.c:4398 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x440499 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffe1f3bfb18 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 0000000000440499 RDX: 0000000000000048 RSI: 0000000020000600 RDI: 000000000000000a RBP: 00000000006ca018 R08: 0000000000000000 R09: 00000000004002c8 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000401ca0 R13: 0000000000401d30 R14: 0000000000000000 R15: 0000000000000000
This is because we didn't filter out too big ctx_size_in. Fix it by rejecting ctx_size_in that are bigger than MAX_BPF_FUNC_ARGS (12) u64 numbers.
Fixes: 1b4d60ec162f ("bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint") Reported-by: syzbot+4f98876664c7337a4ae6@syzkaller.appspotmail.com Signed-off-by: Song Liu songliubraving@fb.com Signed-off-by: Alexei Starovoitov ast@kernel.org Acked-by: Yonghong Song yhs@fb.com Link: https://lore.kernel.org/bpf/20210112234254.1906829-1-songliubraving@fb.com Signed-off-by: Sasha Levin sashal@kernel.org --- net/bpf/test_run.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index c1c30a9f76f34..8b796c499cbb2 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -272,7 +272,8 @@ int bpf_prog_test_run_raw_tp(struct bpf_prog *prog, kattr->test.repeat) return -EINVAL;
- if (ctx_size_in < prog->aux->max_ctx_offset) + if (ctx_size_in < prog->aux->max_ctx_offset || + ctx_size_in > MAX_BPF_FUNC_ARGS * sizeof(u64)) return -EINVAL;
if ((kattr->test.flags & BPF_F_TEST_RUN_ON_CPU) == 0 && cpu != 0)