From 0483748c540114615432edda996416ab0a98324f Mon Sep 17 00:00:00 2001 From: Damien Neil Date: Wed, 22 Mar 2023 09:33:22 -0700 Subject: [PATCH] [release-branch.go1.19] go/scanner: reject large line and column numbers in //line directives # AWS EKS Backported To: go-1.16.15-eks Backported On: Wed, 5 Apr 2023 Backported By: kodurub@amazon.com Backported From: release-branch.go1.19 Source Commit: https://github.com/golang/go/commit/126a1d02da82f93ede7ce0bd8d3c51ef627f2104 Setting a large line or column number using a //line directive can cause integer overflow even in small source files. Limit line and column numbers in //line directives to 2^30-1, which is small enough to avoid int32 overflow on all reasonbly-sized files. Fixes CVE-2023-24537 Fixes #59273 For #59180 Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1802456 Reviewed-by: Julie Qiu Reviewed-by: Roland Shoemaker Run-TryBot: Damien Neil Reviewed-on: https://team-review.git.corp.google.com/c/golang/go-private/+/1802611 Reviewed-by: Damien Neil Change-Id: Ifdfa192d54f722d781a4d8c5f35b5fb72d122168 Reviewed-on: https://go-review.googlesource.com/c/go/+/481986 Reviewed-by: Matthew Dempsky TryBot-Result: Gopher Robot Run-TryBot: Michael Knyszek Auto-Submit: Michael Knyszek --- src/go/parser/parser_test.go | 16 ++++++++++++++++ src/go/scanner/scanner.go | 7 +++++-- 2 files changed, 21 insertions(+), 2 deletions(-) diff --git a/src/go/parser/parser_test.go b/src/go/parser/parser_test.go index a4f882d368..6f812b7d3e 100644 --- a/src/go/parser/parser_test.go +++ b/src/go/parser/parser_test.go @@ -577,3 +577,19 @@ type x int // comment t.Errorf("got %q, want %q", comment, "// comment") } } + +// TestIssue59180 tests that line number overflow doesn't cause an infinite loop. +func TestIssue59180(t *testing.T) { + testcases := []string{ + "package p\n//line :9223372036854775806\n\n//", + "package p\n//line :1:9223372036854775806\n\n//", + "package p\n//line file:9223372036854775806\n\n//", + } + + for _, src := range testcases { + _, err := ParseFile(token.NewFileSet(), "", src, ParseComments) + if err == nil { + t.Errorf("ParseFile(%s) succeeded unexpectedly", src) + } + } +} diff --git a/src/go/scanner/scanner.go b/src/go/scanner/scanner.go index 00fe2dc0b1..d4de23db6a 100644 --- a/src/go/scanner/scanner.go +++ b/src/go/scanner/scanner.go @@ -246,13 +246,16 @@ func (s *Scanner) updateLineInfo(next, offs int, text []byte) { return } + // Put a cap on the maximum size of line and column numbers. + // 30 bits allows for some additional space before wrapping an int32. + const maxLineCol = 1<<30 - 1 var line, col int i2, n2, ok2 := trailingDigits(text[:i-1]) if ok2 { //line filename:line:col i, i2 = i2, i line, col = n2, n - if col == 0 { + if col == 0 || col > maxLineCol { s.error(offs+i2, "invalid column number: "+string(text[i2:])) return } @@ -262,7 +265,7 @@ func (s *Scanner) updateLineInfo(next, offs int, text []byte) { line = n } - if line == 0 { + if line == 0 || line > maxLineCol { s.error(offs+i, "invalid line number: "+string(text[i:])) return } -- 2.39.1