diff --git a/models/issues/pull.go b/models/issues/pull.go
index 0781fd0a2d..188ef00814 100644
--- a/models/issues/pull.go
+++ b/models/issues/pull.go
@@ -5,6 +5,7 @@
 package issues
 
 import (
+	"bufio"
 	"context"
 	"errors"
 	"fmt"
@@ -923,31 +924,30 @@ func MergeBlockedByOutdatedBranch(protectBranch *git_model.ProtectedBranch, pr *
 	return protectBranch.BlockOnOutdatedBranch && pr.CommitsBehind > 0
 }
 
-// GetCodeOwnersFromContent returns the code owners configuration
-// Return empty slice if files missing
+// GetCodeOwnersFromReader returns the code owners configuration
 // Return warning messages on parsing errors
 // We're trying to do the best we can when parsing a file.
 // Invalid lines are skipped. Non-existent users and teams too.
-func GetCodeOwnersFromContent(ctx context.Context, data string) ([]*CodeOwnerRule, []string) {
-	if len(data) == 0 {
-		return nil, nil
-	}
+func GetCodeOwnersFromReader(ctx context.Context, rc io.ReadCloser, truncated bool) ([]*CodeOwnerRule, []string) {
+	defer rc.Close()
+	scanner := bufio.NewScanner(rc)
 
-	rules := make([]*CodeOwnerRule, 0)
-	lines := strings.Split(data, "\n")
-	warnings := make([]string, 0)
+	var rules []*CodeOwnerRule
+	var warnings []string
+	line := 0
+	for scanner.Scan() {
+		line++
 
-	for i, line := range lines {
-		tokens := TokenizeCodeOwnersLine(line)
+		tokens := TokenizeCodeOwnersLine(scanner.Text())
 		if len(tokens) == 0 {
 			continue
 		} else if len(tokens) < 2 {
-			warnings = append(warnings, fmt.Sprintf("Line: %d: incorrect format", i+1))
+			warnings = append(warnings, fmt.Sprintf("Line: %d: incorrect format", line))
 			continue
 		}
 		rule, wr := ParseCodeOwnersLine(ctx, tokens)
 		for _, w := range wr {
-			warnings = append(warnings, fmt.Sprintf("Line: %d: %s", i+1, w))
+			warnings = append(warnings, fmt.Sprintf("Line: %d: %s", line, w))
 		}
 		if rule == nil {
 			continue
@@ -955,6 +955,12 @@ func GetCodeOwnersFromContent(ctx context.Context, data string) ([]*CodeOwnerRul
 
 		rules = append(rules, rule)
 	}
+	if err := scanner.Err(); err != nil {
+		warnings = append(warnings, err.Error())
+	}
+	if truncated {
+		warnings = append(warnings, fmt.Sprintf("File too big: truncated while on line %d", line))
+	}
 
 	return rules, warnings
 }
diff --git a/routers/web/repo/view.go b/routers/web/repo/view.go
index c7cc715fc1..d958a11f55 100644
--- a/routers/web/repo/view.go
+++ b/routers/web/repo/view.go
@@ -439,8 +439,8 @@ func renderFile(ctx *context.Context, entry *git.TreeEntry) {
 			ctx.Data["FileError"] = ctx.Locale.Tr("actions.runs.invalid_workflow_helper", workFlowErr.Error())
 		}
 	} else if slices.Contains([]string{"CODEOWNERS", "docs/CODEOWNERS", ".gitea/CODEOWNERS"}, ctx.Repo.TreePath) {
-		if data, err := blob.GetBlobContent(setting.UI.MaxDisplayFileSize); err == nil {
-			_, warnings := issue_model.GetCodeOwnersFromContent(ctx, data)
+		if rc, size, err := blob.NewTruncatedReader(setting.UI.MaxDisplayFileSize); err == nil {
+			_, warnings := issue_model.GetCodeOwnersFromReader(ctx, rc, size > setting.UI.MaxDisplayFileSize)
 			if len(warnings) > 0 {
 				ctx.Data["FileWarning"] = strings.Join(warnings, "\n")
 			}
diff --git a/services/issue/pull.go b/services/issue/pull.go
index b0a0c47d88..2eef1fbfa8 100644
--- a/services/issue/pull.go
+++ b/services/issue/pull.go
@@ -43,8 +43,6 @@ type ReviewRequestNotifier struct {
 }
 
 func PullRequestCodeOwnersReview(ctx context.Context, issue *issues_model.Issue, pr *issues_model.PullRequest) ([]*ReviewRequestNotifier, error) {
-	files := []string{"CODEOWNERS", "docs/CODEOWNERS", ".gitea/CODEOWNERS"}
-
 	if pr.IsWorkInProgress(ctx) {
 		return nil, nil
 	}
@@ -72,18 +70,17 @@ func PullRequestCodeOwnersReview(ctx context.Context, issue *issues_model.Issue,
 		return nil, err
 	}
 
-	var data string
-	for _, file := range files {
+	var rules []*issues_model.CodeOwnerRule
+	for _, file := range []string{"CODEOWNERS", "docs/CODEOWNERS", ".gitea/CODEOWNERS"} {
 		if blob, err := commit.GetBlobByPath(file); err == nil {
-			data, err = blob.GetBlobContent(setting.UI.MaxDisplayFileSize)
+			rc, size, err := blob.NewTruncatedReader(setting.UI.MaxDisplayFileSize)
 			if err == nil {
+				rules, _ = issues_model.GetCodeOwnersFromReader(ctx, rc, size > setting.UI.MaxDisplayFileSize)
 				break
 			}
 		}
 	}
 
-	rules, _ := issues_model.GetCodeOwnersFromContent(ctx, data)
-
 	// get the mergebase
 	mergeBase, err := getMergeBase(repo, pr, git.BranchPrefix+pr.BaseBranch, pr.GetGitRefName())
 	if err != nil {