diff options
| author | Håvard Haugen <havard.haugen@gmail.com> | 2015-05-25 23:14:35 +0200 |
|---|---|---|
| committer | Rob Pike <r@golang.org> | 2015-06-02 13:55:40 +0000 |
| commit | 70cf7352b488f68141cf73ba35cdfe7c158964fd (patch) | |
| tree | 42e5ce28bcd7ddcf78ebfb9ab47024dda835e2b3 /src | |
| parent | 9378493d1641fd56d5935cb2f6d4f4b2a864894c (diff) | |
| download | go-70cf7352b488f68141cf73ba35cdfe7c158964fd.tar.xz | |
fmt: fix buffer underflow for negative integers
Allow room for the initial minus sign of negative integers when
computing widths.
Fixes #10945.
Change-Id: I04d80203aaff64611992725d613ec13ed2ae721f
Reviewed-on: https://go-review.googlesource.com/10393
Reviewed-by: Rob Pike <r@golang.org>
Diffstat (limited to 'src')
| -rw-r--r-- | src/fmt/fmt_test.go | 3 | ||||
| -rw-r--r-- | src/fmt/format.go | 14 |
2 files changed, 8 insertions, 9 deletions
diff --git a/src/fmt/fmt_test.go b/src/fmt/fmt_test.go index 93121bb3d0..059d09e1bf 100644 --- a/src/fmt/fmt_test.go +++ b/src/fmt/fmt_test.go @@ -557,10 +557,11 @@ var fmtTests = []struct { {"%0.100f", 1.0, zeroFill("1.", 100, "")}, {"%0.100f", -1.0, zeroFill("-1.", 100, "")}, - // Used to panic: integer function didn't look at f.prec or f.unicode or f.width. + // Used to panic: integer function didn't look at f.prec, f.unicode, f.width or sign. {"%#.80x", 42, "0x0000000000000000000000000000000000000000000000000000000000000000000000000000002a"}, {"%.80U", 42, "U+0000000000000000000000000000000000000000000000000000000000000000000000000000002A"}, {"%#.80U", '日', "U+000000000000000000000000000000000000000000000000000000000000000000000000000065E5 '日'"}, + {"%.65d", -44, "-00000000000000000000000000000000000000000000000000000000000000044"}, {"%+.65d", 44, "+00000000000000000000000000000000000000000000000000000000000000044"}, {"% .65d", 44, " 00000000000000000000000000000000000000000000000000000000000000044"}, {"% +.65d", 44, "+00000000000000000000000000000000000000000000000000000000000000044"}, diff --git a/src/fmt/format.go b/src/fmt/format.go index ba984cf84f..ac9f6d881a 100644 --- a/src/fmt/format.go +++ b/src/fmt/format.go @@ -162,6 +162,11 @@ func (f *fmt) integer(a int64, base uint64, signedness bool, digits string) { return } + negative := signedness == signed && a < 0 + if negative { + a = -a + } + var buf []byte = f.intbuf[0:] if f.widPresent || f.precPresent || f.plus || f.space { width := f.wid + f.prec // Only one will be set, both are positive; this provides the maximum. @@ -177,9 +182,7 @@ func (f *fmt) integer(a int64, base uint64, signedness bool, digits string) { width += 1 + 1 + utf8.UTFMax + 1 } } - if f.plus { - width++ - } else if f.space { + if negative || f.plus || f.space { width++ } if width > nByte { @@ -188,11 +191,6 @@ func (f *fmt) integer(a int64, base uint64, signedness bool, digits string) { } } - negative := signedness == signed && a < 0 - if negative { - a = -a - } - // two ways to ask for extra leading zero digits: %.3d or %03d. // apparently the first cancels the second. prec := 0 |