Bug #13954: Etc.getpwnam, getgrnam が SHARABLE_MIDDLE_SUBSTRING=1 を考慮していない

• Status: Closed
• Assignee: -
• Target version: -
• ruby -v: ruby 2.5.0dev (2017-09-29 trunk 60062) [x86_64-linux]
• Backport: 2.3: DONE, 2.4: DONE

[tommy (Masahiro Tomita)]

SHARABLE_MIDDLE_SUBSTRING=1 でコンパイルしたRubyで Etc.getpwnam, getgrnam が共有元の文字列終端まで使用してしまいます。

% sudo useradd abcdefghijklmnopqrstuvwxyz
% ruby -retc -e 'p Etc.getpwnam("abcdefghijklmnopqrstuvwxyz")'           
#<struct Etc::Passwd name="abcdefghijklmnopqrstuvwxyz", passwd="x", uid=1002, gid=1002, gecos="", dir="/home/abcdefghijklmnopqrstuvwxyz", shell="">
% ruby -retc -e 'p Etc.getpwnam(("abcdefghijklmnopqrstuvwxyz"*10)[0,26])'
Traceback (most recent call last):
	1: from -e:1:in `<main>'
-e:1:in `getpwnam': can't find user for abcdefghijklmnopqrstuvwxyz (ArgumentError)

次のパッチで直ると思います。

diff --git a/ext/etc/etc.c b/ext/etc/etc.c
index 5d964ba518..66fd26f436 100644
--- a/ext/etc/etc.c
+++ b/ext/etc/etc.c
@@ -217,6 +217,7 @@ etc_getpwnam(VALUE obj, VALUE nam)
     struct passwd *pwd;
 
     SafeStringValue(nam);
+    StringValueCStr(nam);
     pwd = getpwnam(RSTRING_PTR(nam));
     if (pwd == 0) rb_raise(rb_eArgError, "can't find user for %"PRIsVALUE, nam);
     return setup_passwd(pwd);
@@ -460,6 +461,7 @@ etc_getgrnam(VALUE obj, VALUE nam)
     struct group *grp;
 
     SafeStringValue(nam);
+    StringValueCStr(nam);
     grp = getgrnam(RSTRING_PTR(nam));
     if (grp == 0) rb_raise(rb_eArgError, "can't find group for %"PRIsVALUE, nam);
     return setup_group(grp);

[nobu (Nobuyoshi Nakada)]

• Status changed from Open to Closed

[nobu (Nobuyoshi Nakada)]

• Backport changed from 2.3: UNKNOWN, 2.4: UNKNOWN to 2.3: REQUIRED, 2.4: REQUIRED

[nagachika (Tomoyuki Chikanaga)]

• Backport changed from 2.3: REQUIRED, 2.4: REQUIRED to 2.3: REQUIRED, 2.4: DONE

[nagachika (Tomoyuki Chikanaga)]

ruby_2_4 r61456 merged revision(s) 60071.

[usa (Usaku NAKAMURA)]

• Backport changed from 2.3: REQUIRED, 2.4: DONE to 2.3: DONE, 2.4: DONE

ruby_2_3 r62140 merged revision(s) 60071.