bpf: Fix verifier crash on BPF_NEG with pointer register #6080
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Upstream branch: 4ef77dd |
In check_alu_op(), the verifier currently calls check_reg_arg() and adjust_scalar_min_max_vals() unconditionally for BPF_NEG operations. However, if the destination register holds a pointer, these scalar adjustments are unnecessary and potentially incorrect. This patch adds a check to skip the adjustment logic when the destination register contains a pointer. Reported-by: [email protected] Closes: https://syzkaller.appspot.com/bug?extid=d36d5ae81e1b0a53ef58 Fixes: aced132 ("bpf: Add range tracking for BPF_NEG") Suggested-by: KaFai Wan <[email protected]> Suggested-by: Eduard Zingerman <[email protected]> Signed-off-by: Brahmajit Das <[email protected]> Acked-by: Eduard Zingerman <[email protected]>
Add a test case for BPF_NEG operation on CONST_PTR_TO_MAP. Tests if BPF_NEG operation on map_ptr is rejected in unprivileged mode and is a scalar value and do not trigger Oops in privileged mode. Signed-off-by: KaFai Wan <[email protected]> Acked-by: Eduard Zingerman <[email protected]>
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Upstream branch: 4ef77dd |
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At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=1007800 irrelevant now. Closing PR. |
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Pull request for series with
subject: bpf: Fix verifier crash on BPF_NEG with pointer register
version: 4
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=1007800