From: Naveen N. Rao Date: Thu, 6 Jan 2022 11:45:06 +0000 (+0530) Subject: powerpc32/bpf: Fix codegen for bpf-to-bpf calls X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=2f262cadff57424e81e43bbccd381ae166da7a4b;p=linux.git powerpc32/bpf: Fix codegen for bpf-to-bpf calls commit fab07611fb2e6a15fac05c4583045ca5582fd826 upstream. Pad instructions emitted for BPF_CALL so that the number of instructions generated does not change for different function addresses. This is especially important for calls to other bpf functions, whose address will only be known during extra pass. Fixes: 51c66ad849a703 ("powerpc/bpf: Implement extended BPF on PPC32") Cc: stable@vger.kernel.org # v5.13+ Signed-off-by: Naveen N. Rao Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/52d8fe51f7620a6f27f377791564d79d75463576.1641468127.git.naveen.n.rao@linux.vnet.ibm.com Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/powerpc/net/bpf_jit_comp32.c b/arch/powerpc/net/bpf_jit_comp32.c index 0da31d41d4131..f2c28c9268ef6 100644 --- a/arch/powerpc/net/bpf_jit_comp32.c +++ b/arch/powerpc/net/bpf_jit_comp32.c @@ -191,6 +191,9 @@ void bpf_jit_emit_func_call_rel(u32 *image, struct codegen_context *ctx, u64 fun if (image && rel < 0x2000000 && rel >= -0x2000000) { PPC_BL_ABS(func); + EMIT(PPC_RAW_NOP()); + EMIT(PPC_RAW_NOP()); + EMIT(PPC_RAW_NOP()); } else { /* Load function address into r0 */ EMIT(PPC_RAW_LIS(_R0, IMM_H(func)));