Forwarded: Re: [syzbot] [bpf?] WARNING in bpf_bprintf_prepare (3)

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Subject: Re: [syzbot] [bpf?] WARNING in bpf_bprintf_prepare (3)
Author: chandna.sahil@gmail.com

#syz test
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -1021,7 +1021,9 @@ u32 bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
                      (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
         flow_keys->flags = flags;

+       preempt_disable();
         result = bpf_prog_run_pin_on_cpu(prog, ctx);
+       preempt_enable();

         flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
         flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
--
2.50.1