kernel/git/stable/linux-stable.git/arch/powerpc/net, branch linux-5.14.y

powerpc/bpf: Fix write protecting JIT code

2021-11-17T10:04:50+00:00

commit 44a8214de96bafb5210e43bfa2c97c19bf75af3d upstream. Running program with bpf-to-bpf function calls results in data access exception (0x300) with the below call trace: bpf_int_jit_compile+0x238/0x750 (unreliable) bpf_check+0x2008/0x2710 bpf_prog_load+0xb00/0x13a0 __sys_bpf+0x6f4/0x27c0 sys_bpf+0x2c/0x40 system_call_exception+0x164/0x330 system_call_vectored_common+0xe8/0x278 as bpf_int_jit_compile() tries writing to write protected JIT code location during the extra pass. Fix it by holding off write protection of JIT code until the extra pass, where branch target addresses fixup happens. Fixes: 62e3d4210ac9 ("powerpc/bpf: Write protect JIT code") Cc: stable@vger.kernel.org # v5.14+ Signed-off-by: Hari Bathini Reviewed-by: Naveen N. Rao Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20211025055649.114728-1-hbathini@linux.ibm.com Signed-off-by: Greg Kroah-Hartman

powerpc/bpf: Emit stf barrier instruction sequences for BPF_NOSPEC

2021-10-27T07:59:33+00:00

[ Upstream commit b7540d62509453263604a155bf2d5f0ed450cba2 ] Emit similar instruction sequences to commit a048a07d7f4535 ("powerpc/64s: Add support for a store forwarding barrier at kernel entry/exit") when encountering BPF_NOSPEC. Mitigations are enabled depending on what the firmware advertises. In particular, we do not gate these mitigations based on current settings, just like in x86. Due to this, we don't need to take any action if mitigations are enabled or disabled at runtime. Signed-off-by: Naveen N. Rao Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/956570cbc191cd41f8274bed48ee757a86dac62a.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/bpf: Validate branch ranges

2021-10-27T07:59:33+00:00

[ Upstream commit 3832ba4e283d7052b783dab8311df7e3590fed93 ] Add checks to ensure that we never emit branch instructions with truncated branch offsets. Suggested-by: Michael Ellerman Signed-off-by: Naveen N. Rao Tested-by: Johan Almbladh Reviewed-by: Christophe Leroy Acked-by: Song Liu Acked-by: Johan Almbladh Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/71d33a6b7603ec1013c9734dd8bdd4ff5e929142.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/lib: Add helper to check if offset is within conditional branch range

2021-10-27T07:59:32+00:00

[ Upstream commit 4549c3ea3160fa8b3f37dfe2f957657bb265eda9 ] Add a helper to check if a given offset is within the branch range for a powerpc conditional branch instruction, and update some sites to use the new helper. Signed-off-by: Naveen N. Rao Reviewed-by: Christophe Leroy Acked-by: Song Liu Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/442b69a34ced32ca346a0d9a855f3f6cfdbbbd41.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/bpf ppc32: Fix BPF_SUB when imm == 0x80000000

2021-10-13T07:42:03+00:00

[ Upstream commit 548b762763b885b81850db676258df47c55dd5f9 ] Special case handling of the smallest 32-bit negative number for BPF_SUB. Fixes: 51c66ad849a703 ("powerpc/bpf: Implement extended BPF on PPC32") Signed-off-by: Naveen N. Rao Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/7135360a0cdf70adedbccf9863128b8daef18764.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/bpf ppc32: Do not emit zero extend instruction for 64-bit BPF_END

2021-10-13T07:42:02+00:00

[ Upstream commit 48164fccdff6d5cc11308126c050bd25a329df25 ] Suppress emitting zero extend instruction for 64-bit BPF_END_FROM_[L|B]E operation. Fixes: 51c66ad849a703 ("powerpc/bpf: Implement extended BPF on PPC32") Signed-off-by: Naveen N. Rao Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/b4e3c3546121315a8e2059b19a1bda84971816e4.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/bpf ppc32: Fix JMP32_JSET_K

2021-10-13T07:42:02+00:00

[ Upstream commit e8278d44443207bb6609c7b064073f353e6f4978 ] 'andi' only takes an unsigned 16-bit value. Correct the imm range used when emitting andi. Fixes: 51c66ad849a703 ("powerpc/bpf: Implement extended BPF on PPC32") Signed-off-by: Naveen N. Rao Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/b94489f52831305ec15aca4dd04a3527236be7e8.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/bpf ppc32: Fix ALU32 BPF_ARSH operation

2021-10-13T07:42:02+00:00

[ Upstream commit c9b8da77f22d28348d1f89a6c4d3fec102e9b1c4 ] Correct the destination register used for ALU32 BPF_ARSH operation. Fixes: 51c66ad849a703 ("powerpc/bpf: Implement extended BPF on PPC32") Signed-off-by: Naveen N. Rao Reviewed-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/6d24c1f9e79b6f61f5135eaf2ea1e8bcd4dac87b.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/bpf: Fix BPF_SUB when imm == 0x80000000

2021-10-13T07:42:02+00:00

[ Upstream commit 5855c4c1f415ca3ba1046e77c0b3d3dfc96c9025 ] We aren't handling subtraction involving an immediate value of 0x80000000 properly. Fix the same. Fixes: 156d0e290e969c ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF") Signed-off-by: Naveen N. Rao Reviewed-by: Christophe Leroy [mpe: Fold in fix from Naveen to use imm <= 32768] Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/fc4b1276eb10761fd7ce0814c8dd089da2815251.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin

powerpc/bpf: Fix BPF_MOD when imm == 1

2021-10-13T07:42:02+00:00

[ Upstream commit 8bbc9d822421d9ac8ff9ed26a3713c9afc69d6c8 ] Only ignore the operation if dividing by 1. Fixes: 156d0e290e969c ("powerpc/ebpf/jit: Implement JIT compiler for extended BPF") Signed-off-by: Naveen N. Rao Tested-by: Johan Almbladh Reviewed-by: Christophe Leroy Acked-by: Song Liu Acked-by: Johan Almbladh Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/c674ca18c3046885602caebb326213731c675d06.1633464148.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Sasha Levin