4.19-stable patches

added patches:
	s390-bpf-fix-optimizing-out-zero-extensions.patch

diff --git a/queue-4.19/s390-bpf-fix-optimizing-out-zero-extensions.patch b/queue-4.19/s390-bpf-fix-optimizing-out-zero-extensions.patch
new file mode 100644 (file)
index 0000000..93d90f4
--- /dev/null
+++ b/queue-4.19/s390-bpf-fix-optimizing-out-zero-extensions.patch
@@ -0,0 +1,128 @@
+From db7bee653859ef7179be933e7d1384644f795f26 Mon Sep 17 00:00:00 2001
+From: Ilya Leoshkevich <iii@linux.ibm.com>
+Date: Mon, 6 Sep 2021 15:04:14 +0200
+Subject: s390/bpf: Fix optimizing out zero-extensions
+
+From: Ilya Leoshkevich <iii@linux.ibm.com>
+
+commit db7bee653859ef7179be933e7d1384644f795f26 upstream.
+
+Currently the JIT completely removes things like `reg32 += 0`,
+however, the BPF_ALU semantics requires the target register to be
+zero-extended in such cases.
+
+Fix by optimizing out only the arithmetic operation, but not the
+subsequent zero-extension.
+
+Reported-by: Johan Almbladh <johan.almbladh@anyfinetworks.com>
+Fixes: 054623105728 ("s390/bpf: Add s390x eBPF JIT compiler backend")
+Reviewed-by: Heiko Carstens <hca@linux.ibm.com>
+Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
+Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ arch/s390/net/bpf_jit_comp.c |   50 ++++++++++++++++++++++---------------------
+ 1 file changed, 26 insertions(+), 24 deletions(-)
+
+--- a/arch/s390/net/bpf_jit_comp.c
++++ b/arch/s390/net/bpf_jit_comp.c
+@@ -561,10 +561,10 @@ static noinline int bpf_jit_insn(struct
+               EMIT4(0xb9080000, dst_reg, src_reg);
+               break;
+       case BPF_ALU | BPF_ADD | BPF_K: /* dst = (u32) dst + (u32) imm */
+-              if (!imm)
+-                      break;
+-              /* alfi %dst,imm */
+-              EMIT6_IMM(0xc20b0000, dst_reg, imm);
++              if (imm != 0) {
++                      /* alfi %dst,imm */
++                      EMIT6_IMM(0xc20b0000, dst_reg, imm);
++              }
+               EMIT_ZERO(dst_reg);
+               break;
+       case BPF_ALU64 | BPF_ADD | BPF_K: /* dst = dst + imm */
+@@ -586,10 +586,10 @@ static noinline int bpf_jit_insn(struct
+               EMIT4(0xb9090000, dst_reg, src_reg);
+               break;
+       case BPF_ALU | BPF_SUB | BPF_K: /* dst = (u32) dst - (u32) imm */
+-              if (!imm)
+-                      break;
+-              /* alfi %dst,-imm */
+-              EMIT6_IMM(0xc20b0000, dst_reg, -imm);
++              if (imm != 0) {
++                      /* alfi %dst,-imm */
++                      EMIT6_IMM(0xc20b0000, dst_reg, -imm);
++              }
+               EMIT_ZERO(dst_reg);
+               break;
+       case BPF_ALU64 | BPF_SUB | BPF_K: /* dst = dst - imm */
+@@ -616,10 +616,10 @@ static noinline int bpf_jit_insn(struct
+               EMIT4(0xb90c0000, dst_reg, src_reg);
+               break;
+       case BPF_ALU | BPF_MUL | BPF_K: /* dst = (u32) dst * (u32) imm */
+-              if (imm == 1)
+-                      break;
+-              /* msfi %r5,imm */
+-              EMIT6_IMM(0xc2010000, dst_reg, imm);
++              if (imm != 1) {
++                      /* msfi %r5,imm */
++                      EMIT6_IMM(0xc2010000, dst_reg, imm);
++              }
+               EMIT_ZERO(dst_reg);
+               break;
+       case BPF_ALU64 | BPF_MUL | BPF_K: /* dst = dst * imm */
+@@ -670,6 +670,8 @@ static noinline int bpf_jit_insn(struct
+                       if (BPF_OP(insn->code) == BPF_MOD)
+                               /* lhgi %dst,0 */
+                               EMIT4_IMM(0xa7090000, dst_reg, 0);
++                      else
++                              EMIT_ZERO(dst_reg);
+                       break;
+               }
+               /* lhi %w0,0 */
+@@ -762,10 +764,10 @@ static noinline int bpf_jit_insn(struct
+               EMIT4(0xb9820000, dst_reg, src_reg);
+               break;
+       case BPF_ALU | BPF_XOR | BPF_K: /* dst = (u32) dst ^ (u32) imm */
+-              if (!imm)
+-                      break;
+-              /* xilf %dst,imm */
+-              EMIT6_IMM(0xc0070000, dst_reg, imm);
++              if (imm != 0) {
++                      /* xilf %dst,imm */
++                      EMIT6_IMM(0xc0070000, dst_reg, imm);
++              }
+               EMIT_ZERO(dst_reg);
+               break;
+       case BPF_ALU64 | BPF_XOR | BPF_K: /* dst = dst ^ imm */
+@@ -786,10 +788,10 @@ static noinline int bpf_jit_insn(struct
+               EMIT6_DISP_LH(0xeb000000, 0x000d, dst_reg, dst_reg, src_reg, 0);
+               break;
+       case BPF_ALU | BPF_LSH | BPF_K: /* dst = (u32) dst << (u32) imm */
+-              if (imm == 0)
+-                      break;
+-              /* sll %dst,imm(%r0) */
+-              EMIT4_DISP(0x89000000, dst_reg, REG_0, imm);
++              if (imm != 0) {
++                      /* sll %dst,imm(%r0) */
++                      EMIT4_DISP(0x89000000, dst_reg, REG_0, imm);
++              }
+               EMIT_ZERO(dst_reg);
+               break;
+       case BPF_ALU64 | BPF_LSH | BPF_K: /* dst = dst << imm */
+@@ -811,10 +813,10 @@ static noinline int bpf_jit_insn(struct
+               EMIT6_DISP_LH(0xeb000000, 0x000c, dst_reg, dst_reg, src_reg, 0);
+               break;
+       case BPF_ALU | BPF_RSH | BPF_K: /* dst = (u32) dst >> (u32) imm */
+-              if (imm == 0)
+-                      break;
+-              /* srl %dst,imm(%r0) */
+-              EMIT4_DISP(0x88000000, dst_reg, REG_0, imm);
++              if (imm != 0) {
++                      /* srl %dst,imm(%r0) */
++                      EMIT4_DISP(0x88000000, dst_reg, REG_0, imm);
++              }
+               EMIT_ZERO(dst_reg);
+               break;
+       case BPF_ALU64 | BPF_RSH | BPF_K: /* dst = dst >> imm */

diff --git a/queue-4.19/series b/queue-4.19/series
new file mode 100644 (file)
index 0000000..a206d1d
--- /dev/null
+++ b/queue-4.19/series
@@ -0,0 +1 @@
+s390-bpf-fix-optimizing-out-zero-extensions.patch