From: Jesse Hathaway <jesse@mbuki-mvuki.org>
To: Andreas Schwab <schwab@linux-m68k.org>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>,
libc-alpha@sourceware.org
Subject: Re: [PATCH] getlogin_r: return early when linux sentinel value is set
Date: Mon, 26 Mar 2018 14:22:00 -0000 [thread overview]
Message-ID: <CANSNSoX7WFZm9fUEJ43A=CH8tQ+m7ZtGHqJsAfkY-AOqZbFMzA@mail.gmail.com> (raw)
In-Reply-To: <CANSNSoWK7=NVnjsa4EFrcBwDSfJedNzMsYvKXD_e-M3k6zipRA@mail.gmail.com>
[-- Attachment #1: Type: text/plain, Size: 156 bytes --]
On Thu, Mar 22, 2018 at 2:30 PM, Jesse Hathaway <jesse@mbuki-mvuki.org> wrote:
> fixed, attached
Adhemerval Zanella would you be able to push this for me?
[-- Attachment #2: getlogin_r.c.patch --]
[-- Type: text/x-patch, Size: 1562 bytes --]
commit 7d60c6ab90d23bab16adc2809de95f99e84862d5
Author: Jesse Hathaway <jesse@mbuki-mvuki.org>
Date: Fri Mar 16 10:46:50 2018 -0500
getlogin_r: return early when linux sentinel value is set
When there is no login uid Linux sets /proc/self/loginid to the sentinel
value of, (uid_t) -1. If this is set we can return early and avoid
needlessly looking up the sentinel value in any configured nss
databases.
diff --git a/ChangeLog b/ChangeLog
index 3399e567b8..5d776d995f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2018-03-20 Jesse Hathaway <jesse@mbuki-mvuki.org> (tiny change)
+
+ * sysdeps/unix/sysv/linux/getlogin_r.c (__getlogin_r_loginuid): Return
+ early when linux sentinel value is set.
+
2018-03-20 Samuel Thibault <samuel.thibault@ens-lyon.org>
* manual/errno.texi (EOWNERDEAD, ENOTRECOVERABLE): Remove errno
diff --git a/sysdeps/unix/sysv/linux/getlogin_r.c b/sysdeps/unix/sysv/linux/getlogin_r.c
index 73ea14c8f9..14587712a7 100644
--- a/sysdeps/unix/sysv/linux/getlogin_r.c
+++ b/sysdeps/unix/sysv/linux/getlogin_r.c
@@ -55,6 +55,15 @@ __getlogin_r_loginuid (char *name, size_t namesize)
endp == uidbuf || *endp != '\0'))
return -1;
+ /* If there is no login uid, linux sets /proc/self/loginid to the sentinel
+ value of, (uid_t) -1, so check if that value is set and return early to
+ avoid making unneeded nss lookups. */
+ if (uid == (uid_t) -1)
+ {
+ __set_errno (ENXIO);
+ return ENXIO;
+ }
+
struct passwd pwd;
struct passwd *tpwd;
int result = 0;
next prev parent reply other threads:[~2018-03-26 14:22 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-03-16 16:18 Jesse Hathaway
2018-03-19 15:03 ` Jesse Hathaway
2018-03-20 8:00 ` Adhemerval Zanella
2018-03-20 9:05 ` Andreas Schwab
2018-03-20 17:52 ` Jesse Hathaway
2018-03-20 18:30 ` Andreas Schwab
2018-03-21 21:28 ` Jesse Hathaway
2018-03-22 6:14 ` Adhemerval Zanella
2018-03-22 13:49 ` Jesse Hathaway
2018-03-22 17:35 ` Andreas Schwab
2018-03-22 19:30 ` Jesse Hathaway
2018-03-26 14:22 ` Jesse Hathaway [this message]
2018-03-26 16:30 ` Adhemerval Zanella
2018-03-28 0:37 ` Adhemerval Zanella
2018-04-03 10:46 ` Florian Weimer
2018-04-03 11:41 ` Adhemerval Zanella
2018-04-03 11:45 ` Florian Weimer
2018-04-03 11:53 ` Adhemerval Zanella
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