| Message ID | 1410917578-5122-1-git-send-email-ast@plumgrid.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Alexei Starovoitov <ast@plumgrid.com> Date: Tue, 16 Sep 2014 18:32:58 -0700 > fix several issues in sparc BPF JIT compiler. > > ldx/stx related: > . classic BPF instructions that access mem[] slots were not setting > SEEN_MEM flag, so stack wasn't allocated. Fix that by advertising > correct flags > > . LDX/STX instructions were missing SEEN_XREG, so register value > could have leaked to user space. Fix it. > > . since stack for mem[] slots is allocated with 'sub %sp' instead > of 'save %sp', use %sp as base register instead of %fp. > > . ldx mem[0] means first slot in classic BPF which should have > -4 offset instead of 0. > > . sparc64 needs 2047 stack bias as per ABI to access stack > > . emit_stmem() was using LD32I macro instead of ST32I > > SKF_AD_VLAN_TAG* related: > . SKF_AD_VLAN_TAG_PRESENT must return 1 or 0 instead of '> 0' or 0 > as per classic BPF de facto standard > > . SKF_AD_VLAN_TAG needs to mask the field correctly > > Fixes: 2809a2087cc4 ("net: filter: Just In Time compiler for sparc") > Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Applied and queued up for -stable, thanks! -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/sparc/net/bpf_jit_comp.c b/arch/sparc/net/bpf_jit_comp.c index 1f76c22..51ae87b 100644 --- a/arch/sparc/net/bpf_jit_comp.c +++ b/arch/sparc/net/bpf_jit_comp.c @@ -234,12 +234,18 @@ do { BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u8)); \ __emit_load8(BASE, STRUCT, FIELD, DEST); \ } while (0) -#define emit_ldmem(OFF, DEST) \ -do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(DEST); \ +#ifdef CONFIG_SPARC64 +#define BIAS (STACK_BIAS - 4) +#else +#define BIAS (-4) +#endif + +#define emit_ldmem(OFF, DEST) \ +do { *prog++ = LD32I | RS1(SP) | S13(BIAS - (OFF)) | RD(DEST); \ } while (0) -#define emit_stmem(OFF, SRC) \ -do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(SRC); \ +#define emit_stmem(OFF, SRC) \ +do { *prog++ = ST32I | RS1(SP) | S13(BIAS - (OFF)) | RD(SRC); \ } while (0) #ifdef CONFIG_SMP @@ -615,10 +621,11 @@ void bpf_jit_compile(struct bpf_prog *fp) case BPF_ANC | SKF_AD_VLAN_TAG: case BPF_ANC | SKF_AD_VLAN_TAG_PRESENT: emit_skb_load16(vlan_tci, r_A); - if (code == (BPF_ANC | SKF_AD_VLAN_TAG)) { - emit_andi(r_A, VLAN_VID_MASK, r_A); + if (code != (BPF_ANC | SKF_AD_VLAN_TAG)) { + emit_alu_K(SRL, 12); + emit_andi(r_A, 1, r_A); } else { - emit_loadimm(VLAN_TAG_PRESENT, r_TMP); + emit_loadimm(~VLAN_TAG_PRESENT, r_TMP); emit_and(r_A, r_TMP, r_A); } break; @@ -630,15 +637,19 @@ void bpf_jit_compile(struct bpf_prog *fp) emit_loadimm(K, r_X); break; case BPF_LD | BPF_MEM: + seen |= SEEN_MEM; emit_ldmem(K * 4, r_A); break; case BPF_LDX | BPF_MEM: + seen |= SEEN_MEM | SEEN_XREG; emit_ldmem(K * 4, r_X); break; case BPF_ST: + seen |= SEEN_MEM; emit_stmem(K * 4, r_A); break; case BPF_STX: + seen |= SEEN_MEM | SEEN_XREG; emit_stmem(K * 4, r_X); break;
fix several issues in sparc BPF JIT compiler. ldx/stx related: . classic BPF instructions that access mem[] slots were not setting SEEN_MEM flag, so stack wasn't allocated. Fix that by advertising correct flags . LDX/STX instructions were missing SEEN_XREG, so register value could have leaked to user space. Fix it. . since stack for mem[] slots is allocated with 'sub %sp' instead of 'save %sp', use %sp as base register instead of %fp. . ldx mem[0] means first slot in classic BPF which should have -4 offset instead of 0. . sparc64 needs 2047 stack bias as per ABI to access stack . emit_stmem() was using LD32I macro instead of ST32I SKF_AD_VLAN_TAG* related: . SKF_AD_VLAN_TAG_PRESENT must return 1 or 0 instead of '> 0' or 0 as per classic BPF de facto standard . SKF_AD_VLAN_TAG needs to mask the field correctly Fixes: 2809a2087cc4 ("net: filter: Just In Time compiler for sparc") Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> --- tested on sparc64 qemu with test_bpf, compile tested only on sparc32 After these fixes, test_bpf w/JIT fails only two tests: LD_ABS_LL and LD_ABS_NET. I'm still debugging what's wrong there. arch/sparc/net/bpf_jit_comp.c | 25 ++++++++++++++++++------- 1 file changed, 18 insertions(+), 7 deletions(-)