fix parseInfoFile does not handle spaces in filenames

thaJeztah · thaJeztah · commit c22effb16869 · 2019-04-02T13:06:32.000+02:00
`/proc/self/mountinfo` uses `\040` for spaces, however, `parseInfoFile()`
did not decode those spaces in paths, therefore attempting to use `\040`
as a literal part of the path.

This patch un-quotes the `root` and `mount point` fields to fix
situations where paths contain spaces.

Note that the `mount source` field is not modified, given that
this field is documented (man `PROC(5)`) as:

    filesystem-specific information or "none"

Which I interpreted as "the format in this field is undefined".

Reported-by: Daniil Yaroslavtsev &lt;daniilyar@users.noreply.github.com&gt;
Reported-by: Nathan Ringo &lt;remexre@gmail.com&gt;
Based-on-patch-by: Diego Becciolini &lt;itizir@users.noreply.github.com&gt;
Based-on-patch-by: Sergei Utinski &lt;sergei-utinski@users.noreply.github.com&gt;
Signed-off-by: Sebastiaan van Stijn &lt;github@gone.nl&gt;
diff --git a/mount/mountinfo_linux.go b/mount/mountinfo_linux.go
@@ -25,6 +25,8 @@ import (
 	"os"
 	"strconv"
 	"strings"
+
+	"github.com/pkg/errors"
 )
 
 // Self retrieves a list of mounts for the current running process.
@@ -41,13 +43,15 @@ func Self() ([]Info, error) {
 func parseInfoFile(r io.Reader) ([]Info, error) {
 	s := bufio.NewScanner(r)
 	out := []Info{}
-
+	var err error
 	for s.Scan() {
-		if err := s.Err(); err != nil {
+		if err = s.Err(); err != nil {
 			return nil, err
 		}
 
 		/*
+		   See http://man7.org/linux/man-pages/man5/proc.5.html
+
 		   36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 - ext3 /dev/root rw,errors=continue
 		   (1)(2)(3)   (4)   (5)      (6)      (7)   (8) (9)   (10)         (11)
 		   (1) mount ID:  unique identifier of the mount (may be reused after umount)
@@ -81,8 +85,14 @@ func parseInfoFile(r io.Reader) ([]Info, error) {
 		p.Major, _ = strconv.Atoi(mm[0])
 		p.Minor, _ = strconv.Atoi(mm[1])
 
-		p.Root = fields[3]
-		p.Mountpoint = fields[4]
+		p.Root, err = strconv.Unquote(`"` + fields[3] + `"`)
+		if err != nil {
+			return nil, errors.Wrapf(err, "parsing '%s' failed: unable to unquote root field", fields[3])
+		}
+		p.Mountpoint, err = strconv.Unquote(`"` + fields[4] + `"`)
+		if err != nil {
+			return nil, errors.Wrapf(err, "parsing '%s' failed: unable to unquote mount point field", fields[4])
+		}
 		p.Options = fields[5]
 
 		// one or more optional fields, when a separator (-)
diff --git a/mount/mountinfo_linux_test.go b/mount/mountinfo_linux_test.go
@@ -436,6 +436,9 @@ const (
 286 15 0:3631 / /var/lib/docker/aufs/mnt/ff28c27d5f894363993622de26d5dd352dba072f219e4691d6498c19bbbc15a9 rw,relatime - aufs none rw,si=9b4a7642265b339c
 289 15 0:3634 / /var/lib/docker/aufs/mnt/aa128fe0e64fdede333aa48fd9de39530c91a9244a0f0649a3c411c61e372daa rw,relatime - aufs none rw,si=9b4a764012ada39c
 99 15 8:33 / /media/REMOVE\040ME rw,nosuid,nodev,relatime - fuseblk /dev/sdc1 rw,user_id=0,group_id=0,allow_other,blksize=4096`
+
+	mountInfoWithSpaces = `486 28 252:1 / /mnt/foo\040bar rw,relatime shared:243 - ext4 /dev/vda1 rw,data=ordered
+31 21 0:23 / /DATA/foo_bla_bla rw,relatime - cifs //foo/BLA\040BLA\040BLA/ rw,sec=ntlm,cache=loose,unc=\\foo\BLA BLA BLA,username=my_login,domain=mydomain.com,uid=12345678,forceuid,gid=12345678,forcegid,addr=10.1.30.10,file_mode=0755,dir_mode=0755,nounix,rsize=61440,wsize=65536,actimeo=1`
 )
 
 func TestParseFedoraMountinfo(t *testing.T) {
@@ -490,3 +493,48 @@ func TestParseFedoraMountinfoFields(t *testing.T) {
 		t.Fatalf("expected %#v, got %#v", mi, infos[0])
 	}
 }
+
+func TestParseMountinfoWithSpaces(t *testing.T) {
+	r := bytes.NewBuffer([]byte(mountInfoWithSpaces))
+	infos, err := parseInfoFile(r)
+	if err != nil {
+		t.Fatal(err)
+	}
+	expected := []Info{
+		{
+			ID:         486,
+			Parent:     28,
+			Major:      252,
+			Minor:      1,
+			Root:       "/",
+			Mountpoint: "/mnt/foo bar",
+			Options:    "rw,relatime",
+			Optional:   "shared:243",
+			FSType:     "ext4",
+			Source:     "/dev/vda1",
+			VFSOptions: "rw,data=ordered",
+		},
+		{
+			ID:         31,
+			Parent:     21,
+			Major:      0,
+			Minor:      23,
+			Root:       "/",
+			Mountpoint: "/DATA/foo_bla_bla",
+			Options:    "rw,relatime",
+			Optional:   "",
+			FSType:     "cifs",
+			Source:     `//foo/BLA\040BLA\040BLA/`,
+			VFSOptions: `rw,sec=ntlm,cache=loose,unc=\\foo\BLA`,
+		},
+	}
+
+	if len(infos) != len(expected) {
+		t.Fatalf("expected %d entries, got %d", len(expected), len(infos))
+	}
+	for i, mi := range expected {
+		if infos[i] != mi {
+			t.Fatalf("expected %#v, got %#v", mi, infos[i])
+		}
+	}
+}
