Greg Kroah-Hartman
598cf27219
Link: https://lore.kernel.org/r/20260217200002.683975158@linuxfoundation.org Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Tested-by: Takeshi Ogasawara <takeshi.ogasawara@futuring-girl.com> Tested-by: Peter Schneider <pschneider1968@googlemail.com> Tested-by: Jon Hunter <jonathanh@nvidia.com> Tested-by: Salvatore Bonaccorso <carnil@debian.org> Tested-by: Brett A C Sheffield <bacs@librecast.net> Tested-by: Mark Brown <broonie@kernel.org> Tested-by: Luna Jernberg <droidbittin@gmail.com> Tested-by: Ronald Warsow <rwarsow@gmx.de> Tested-by: Justin M. Forbes <jforbes@fedoraproject.org> Tested-by: Ron Economos <re@w6rz.net> Tested-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
28 lines
840 B
C
28 lines
840 B
C
{
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"BPF_ATOMIC bounds propagation, mem->reg",
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.insns = {
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/* a = 0; */
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/*
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* Note this is implemented with two separate instructions,
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* where you might think one would suffice:
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*
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* BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
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*
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* This is because BPF_ST_MEM doesn't seem to set the stack slot
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* type to 0 when storing an immediate.
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*/
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BPF_MOV64_IMM(BPF_REG_0, 0),
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BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_0, -8),
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/* b = atomic_fetch_add(&a, 1); */
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BPF_MOV64_IMM(BPF_REG_1, 1),
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BPF_ATOMIC_OP(BPF_DW, BPF_ADD | BPF_FETCH, BPF_REG_10, BPF_REG_1, -8),
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/* Verifier should be able to tell that this infinite loop isn't reachable. */
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/* if (b) while (true) continue; */
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BPF_JMP_IMM(BPF_JNE, BPF_REG_1, 0, -1),
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BPF_EXIT_INSN(),
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},
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.result = ACCEPT,
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.result_unpriv = REJECT,
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.errstr_unpriv = "back-edge",
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},
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