Merging upstream version 6.9.8.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 64 insertions, 5 deletions

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 0ef18ae40b..d5fca9deac 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -6223,6 +6223,7 @@ static void set_sext32_default_val(struct bpf_reg_state *reg, int size)
 	}
 	reg->u32_min_value = 0;
 	reg->u32_max_value = U32_MAX;
+	reg->var_off = tnum_subreg(tnum_unknown);
 }
 
 static void coerce_subreg_to_size_sx(struct bpf_reg_state *reg, int size)
@@ -6267,6 +6268,7 @@ static void coerce_subreg_to_size_sx(struct bpf_reg_state *reg, int size)
 		reg->s32_max_value = s32_max;
 		reg->u32_min_value = (u32)s32_min;
 		reg->u32_max_value = (u32)s32_max;
+		reg->var_off = tnum_subreg(tnum_range(s32_min, s32_max));
 		return;
 	}
 
@@ -12544,6 +12546,16 @@ static bool signed_add32_overflows(s32 a, s32 b)
 	return res < a;
 }
 
+static bool signed_add16_overflows(s16 a, s16 b)
+{
+	/* Do the add in u16, where overflow is well-defined */
+	s16 res = (s16)((u16)a + (u16)b);
+
+	if (b < 0)
+		return res > a;
+	return res < a;
+}
+
 static bool signed_sub_overflows(s64 a, s64 b)
 {
 	/* Do the sub in u64, where overflow is well-defined */
@@ -17296,11 +17308,11 @@ static int is_state_visited(struct bpf_verifier_env *env, int insn_idx)
 				goto skip_inf_loop_check;
 			}
 			if (is_may_goto_insn_at(env, insn_idx)) {
-				if (states_equal(env, &sl->state, cur, RANGE_WITHIN)) {
+				if (sl->state.may_goto_depth != cur->may_goto_depth &&
+				    states_equal(env, &sl->state, cur, RANGE_WITHIN)) {
 					update_loop_entry(cur, &sl->state);
 					goto hit;
 				}
-				goto skip_inf_loop_check;
 			}
 			if (calls_callback(env, insn_idx)) {
 				if (states_equal(env, &sl->state, cur, RANGE_WITHIN))
@@ -18562,6 +18574,39 @@ static struct bpf_prog *bpf_patch_insn_data(struct bpf_verifier_env *env, u32 of
 	return new_prog;
 }
 
+/*
+ * For all jmp insns in a given 'prog' that point to 'tgt_idx' insn adjust the
+ * jump offset by 'delta'.
+ */
+static int adjust_jmp_off(struct bpf_prog *prog, u32 tgt_idx, u32 delta)
+{
+	struct bpf_insn *insn = prog->insnsi;
+	u32 insn_cnt = prog->len, i;
+
+	for (i = 0; i < insn_cnt; i++, insn++) {
+		u8 code = insn->code;
+
+		if ((BPF_CLASS(code) != BPF_JMP && BPF_CLASS(code) != BPF_JMP32) ||
+		    BPF_OP(code) == BPF_CALL || BPF_OP(code) == BPF_EXIT)
+			continue;
+
+		if (insn->code == (BPF_JMP32 | BPF_JA)) {
+			if (i + 1 + insn->imm != tgt_idx)
+				continue;
+			if (signed_add32_overflows(insn->imm, delta))
+				return -ERANGE;
+			insn->imm += delta;
+		} else {
+			if (i + 1 + insn->off != tgt_idx)
+				continue;
+			if (signed_add16_overflows(insn->imm, delta))
+				return -ERANGE;
+			insn->off += delta;
+		}
+	}
+	return 0;
+}
+
 static int adjust_subprog_starts_after_remove(struct bpf_verifier_env *env,
 					      u32 off, u32 cnt)
 {
@@ -19309,10 +19354,14 @@ static int jit_subprogs(struct bpf_verifier_env *env)
 	 * bpf_prog_load will add the kallsyms for the main program.
 	 */
 	for (i = 1; i < env->subprog_cnt; i++) {
-		bpf_prog_lock_ro(func[i]);
-		bpf_prog_kallsyms_add(func[i]);
+		err = bpf_prog_lock_ro(func[i]);
+		if (err)
+			goto out_free;
 	}
 
+	for (i = 1; i < env->subprog_cnt; i++)
+		bpf_prog_kallsyms_add(func[i]);
+
 	/* Last step: make now unused interpreter insns from main
 	 * prog consistent for later dump requests, so they can
 	 * later look the same as if they were interpreted only.
@@ -19808,7 +19857,10 @@ static int do_misc_fixups(struct bpf_verifier_env *env)
 
 			stack_depth_extra = 8;
 			insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_AX, BPF_REG_10, stack_off);
-			insn_buf[1] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_AX, 0, insn->off + 2);
+			if (insn->off >= 0)
+				insn_buf[1] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_AX, 0, insn->off + 2);
+			else
+				insn_buf[1] = BPF_JMP_IMM(BPF_JEQ, BPF_REG_AX, 0, insn->off - 1);
 			insn_buf[2] = BPF_ALU64_IMM(BPF_SUB, BPF_REG_AX, 1);
 			insn_buf[3] = BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_AX, stack_off);
 			cnt = 4;
@@ -20266,6 +20318,13 @@ next_insn:
 		if (!new_prog)
 			return -ENOMEM;
 		env->prog = prog = new_prog;
+		/*
+		 * If may_goto is a first insn of a prog there could be a jmp
+		 * insn that points to it, hence adjust all such jmps to point
+		 * to insn after BPF_ST that inits may_goto count.
+		 * Adjustment will succeed because bpf_patch_insn_data() didn't fail.
+		 */
+		WARN_ON(adjust_jmp_off(env->prog, subprog_start, 1));
 	}
 
 	/* Since poke tab is now finalized, publish aux to tracker. */