From patchwork Fri Nov 10 20:08:22 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luke Shumaker X-Patchwork-Id: 836863 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=sourceware.org (client-ip=209.132.180.131; helo=sourceware.org; envelope-from=libc-alpha-return-86965-incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="ISafBjkq"; dkim-atps=neutral Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yYWM40vt2z9t3h for ; Sat, 11 Nov 2017 07:08:47 +1100 (AEDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; q=dns; s=default; b=VP5no7REPihRMIKD3DPneB8WtTfkhw4 nQxccdHCTCE3iB9KQlmKsFmWNDSRzQuG6GvgRn7pCmruI6hS0tiUHkjiwucRHflC 7pomwsh9p4IDujyispb8W/quAnd8u0+APabFF/DBY4C1y4C2GvIfGDkdaQts0JrQ B3ryDNDinnLc= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; s=default; bh=AYkNE2GlrIggPjQfiEy48JoyWcg=; b=ISafB jkqTqiz62sPQtgROIz1hxFgiRDTQuFPnnxT5uxTrKjJpn753rjix4WV29MKPcIg1 /DsjKOiIq49+Zc17pbyHyC5VOqvWir06dpJAEIfzNdqnrY1+CCsMwNs5YaPWFpP0 SwFSHgONm08eBPuMN7DiLxQADJOAHMy7omisx0= Received: (qmail 42682 invoked by alias); 10 Nov 2017 20:08:30 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 42308 invoked by uid 89); 10 Nov 2017 20:08:30 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RP_MATCHES_RCVD, SPF_HELO_PASS, SPF_PASS, URIBL_RED autolearn=ham version=3.3.2 spammy= X-HELO: mav.lukeshu.com From: Luke Shumaker To: libc-alpha@sourceware.org Cc: christian.brauner@mailbox.org Subject: [PATCH v6 1/6] manual: Update to mention ENODEV for ttyname and ttyname_r Date: Fri, 10 Nov 2017 15:08:22 -0500 Message-Id: <20171110200827.32265-2-lukeshu@lukeshu.com> In-Reply-To: <20171110200827.32265-1-lukeshu@lukeshu.com> References: <20171110200827.32265-1-lukeshu@lukeshu.com> From: Luke Shumaker Commit 15e9a4f378c8607c2ae1aa465436af4321db0e23 introduced ENODEV as a possible error condition for ttyname and ttyname_r. Update the manual to mention this GNU extension. v2: - Fix typo: psuedo->pseudo - Improve wording - Fix ChangeLog item name v3: - Revise commit message Reviewed-by: Christian Brauner --- ChangeLog | 5 +++++ manual/terminal.texi | 5 +++++ 2 files changed, 10 insertions(+) diff --git a/ChangeLog b/ChangeLog index bc8c473f09..dc4094bdc3 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2017-11-07 Luke Shumaker + + * manual/terminal.texi (Is It a Terminal): + Mention ENODEV for ttyname and ttyname_r. + 2017-11-07 Joseph Myers * include/float.h diff --git a/manual/terminal.texi b/manual/terminal.texi index 4fef5045b8..4aace48b14 100644 --- a/manual/terminal.texi +++ b/manual/terminal.texi @@ -109,6 +109,11 @@ The @var{filedes} is not associated with a terminal. @item ERANGE The buffer length @var{len} is too small to store the string to be returned. + +@item ENODEV +The @var{filedes} is associated with a terminal device that is a slave +pseudo-terminal, but the file name associated with that device could +not be determined. This is a GNU extension. @end table @end deftypefun From patchwork Fri Nov 10 20:08:23 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luke Shumaker X-Patchwork-Id: 836864 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=sourceware.org (client-ip=209.132.180.131; helo=sourceware.org; envelope-from=libc-alpha-return-86966-incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="ek7lVN6i"; dkim-atps=neutral Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yYWMK49MPz9t3h for ; Sat, 11 Nov 2017 07:09:01 +1100 (AEDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; q=dns; s=default; b=dL9G/F8rIH7v4Bz9oi1MJI4nssXCdbp uIw/UB5eKr0tDd7Yf0l8vHZ66y9DP0dox8Z6KQX5w+SG2g4ZfvKqVQBFH40cShoF WBfevSNiXk+tZx6FuSux2dzh3J07+d+3UB9SeKVeH6doD/bCuW1igOHhgPZZkFO+ rGTmb4FUruuQ= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; s=default; bh=h9QZxSFmjIyia15mAtbXvsrGA8U=; b=ek7lV N6i06eKrO+P7iQkG6irKoDKmMwmWkNguArxTLnWNVjcZAmHmkv25UqGvpJhQwdz/ 6HAgJDDvmih1JJItdRLqFvmE7fok1T3/kH5Z3frjS49IfRO/FnRnCb11lrHrdG66 JOoUTuRHn58sqZkWs4o07ofNwVONJqTgBF6KPM= Received: (qmail 42934 invoked by alias); 10 Nov 2017 20:08:31 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 42708 invoked by uid 89); 10 Nov 2017 20:08:30 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RP_MATCHES_RCVD, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.2 spammy=Hx-languages-length:1431 X-HELO: mav.lukeshu.com From: Luke Shumaker To: libc-alpha@sourceware.org Cc: christian.brauner@mailbox.org Subject: [PATCH v6 2/6] linux ttyname: Update a reference to kernel docs for kernel 4.10 Date: Fri, 10 Nov 2017 15:08:23 -0500 Message-Id: <20171110200827.32265-3-lukeshu@lukeshu.com> In-Reply-To: <20171110200827.32265-1-lukeshu@lukeshu.com> References: <20171110200827.32265-1-lukeshu@lukeshu.com> From: Luke Shumaker Linux 4.10 moved many of the documentation files around. 4.10 came out between the time the patch adding the comment (commit 15e9a4f378c8607c2ae1aa465436af4321db0e23) was submitted and the time it was applied (in February, January, and March 2017; respectively). v2: - No change v3: - Revise commit message - Two spaces after a period in comments Reviewed-by: Christian Brauner --- ChangeLog | 2 ++ sysdeps/unix/sysv/linux/ttyname.h | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index dc4094bdc3..095baf9eb6 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,7 @@ 2017-11-07 Luke Shumaker + * sysdeps/unix/sysv/linux/ttyname.h (is_pty): Update doc reference. + * manual/terminal.texi (Is It a Terminal): Mention ENODEV for ttyname and ttyname_r. diff --git a/sysdeps/unix/sysv/linux/ttyname.h b/sysdeps/unix/sysv/linux/ttyname.h index 2e415e4e9c..cbcdbab607 100644 --- a/sysdeps/unix/sysv/linux/ttyname.h +++ b/sysdeps/unix/sysv/linux/ttyname.h @@ -21,7 +21,8 @@ #include /* Return true if this is a UNIX98 pty device, as defined in - linux/Documentation/devices.txt. */ + linux/Documentation/devices.txt (on linux < 4.10) or + linux/Documentation/admin-guide/devices.txt (on linux >= 4.10). */ static inline int is_pty (struct stat64 *sb) { From patchwork Fri Nov 10 20:08:24 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luke Shumaker X-Patchwork-Id: 836865 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=sourceware.org (client-ip=209.132.180.131; helo=sourceware.org; envelope-from=libc-alpha-return-86967-incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="W5gzoRui"; dkim-atps=neutral Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yYWMZ63x8z9t3h for ; Sat, 11 Nov 2017 07:09:14 +1100 (AEDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; q=dns; s=default; b=bjwlPFzcIuYZD1ybuaXL1hNdqbqtJ/f y2/eJoGUQXQvWAUONrL99b27Tdwq3BMyIQW4OyBubwRLf5/WR7P+fF6dcOLCCvu2 5PrpPEWye/WLV1+i6ON1pKTDw88TsxiRUCYIKXaBJfqP8+kqeLJyxR11EA8LNY7d tQsRhGcwZsK4= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; s=default; bh=F+JyeFOMKIaiqhPvJcnb53E5jaM=; b=W5gzo RuibUBOnb1FijQNE7pZt/m/RzZIvW3vbrxnFNXU5A4im9rK5F0J2No3coNWHB5dk aEulHTW9uBwpTTKU/sxQF/yQH1WFY73xzX6VyHSA/icAzWQBpgfD78pppTSf3uCK KzdKQpjB5EjIaQboezSxyRnBEU/Qatzari1SEo= Received: (qmail 43094 invoked by alias); 10 Nov 2017 20:08:31 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 42926 invoked by uid 89); 10 Nov 2017 20:08:31 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RP_MATCHES_RCVD, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.2 spammy=outcome, Hx-languages-length:1313 X-HELO: mav.lukeshu.com From: Luke Shumaker To: libc-alpha@sourceware.org Cc: christian.brauner@mailbox.org Subject: [PATCH v6 3/6] linux ttyname: Change return type of is_pty from int to bool Date: Fri, 10 Nov 2017 15:08:24 -0500 Message-Id: <20171110200827.32265-4-lukeshu@lukeshu.com> In-Reply-To: <20171110200827.32265-1-lukeshu@lukeshu.com> References: <20171110200827.32265-1-lukeshu@lukeshu.com> From: Luke Shumaker is_pty returning a bool is fine since there's no possible outcome other than true or false, and bool is used throughout the codebase. v2: - Introduce as part of another commit v3: - Split into a separate commit Reviewed-by: Christian Brauner --- ChangeLog | 3 +++ sysdeps/unix/sysv/linux/ttyname.h | 2 +- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/ChangeLog b/ChangeLog index 095baf9eb6..11709a01ac 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,8 @@ 2017-11-07 Luke Shumaker + * sysdeps/unix/sysv/linux/ttyname.h (is_pty): Change return type from + int to bool. + * sysdeps/unix/sysv/linux/ttyname.h (is_pty): Update doc reference. * manual/terminal.texi (Is It a Terminal): diff --git a/sysdeps/unix/sysv/linux/ttyname.h b/sysdeps/unix/sysv/linux/ttyname.h index cbcdbab607..ce4845a587 100644 --- a/sysdeps/unix/sysv/linux/ttyname.h +++ b/sysdeps/unix/sysv/linux/ttyname.h @@ -23,7 +23,7 @@ /* Return true if this is a UNIX98 pty device, as defined in linux/Documentation/devices.txt (on linux < 4.10) or linux/Documentation/admin-guide/devices.txt (on linux >= 4.10). */ -static inline int +static inline bool is_pty (struct stat64 *sb) { #ifdef _STATBUF_ST_RDEV From patchwork Fri Nov 10 20:08:25 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luke Shumaker X-Patchwork-Id: 836874 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=sourceware.org (client-ip=209.132.180.131; helo=sourceware.org; envelope-from=libc-alpha-return-86970-incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="E/07gWcK"; dkim-atps=neutral Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yYWW10RfFz9t3h for ; Sat, 11 Nov 2017 07:15:40 +1100 (AEDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; q=dns; s=default; b=bh5ftxfakK9H2iwU459Q2lfsJ1KR8zc sMX40HQVU6+Zgk6VuVm2SIUWb/qsMV3hl5HvE9RgI46mZLvx3gMRuYo7PwSgx7h3 978IXFcfzi7+OC0VCRNyOi/PbjreoT6PP7lRX0ZHyiz8rfjSRvyfU8gyFNOb+TS9 aqLZYGnxaXQc= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; s=default; bh=BuIXxDWb8YHXjfF3VGpoj8SZHXg=; b=E/07g WcKanPFTBvYimT0I5KajMOomfQqscaWV2quJ/kJ1o5dG4P2ITsHGN4vE3+I46J2G WoreuagT5YOVX2F540d9kmwRsRY7q2nv3+/PsiDHnVSaJz51k6TKDJpO483GQkl8 OFJrVHsrIdisA5P36bG+cz4v3UaywCcxt/Tlxk= Received: (qmail 69008 invoked by alias); 10 Nov 2017 20:15:24 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 68944 invoked by uid 89); 10 Nov 2017 20:15:22 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RP_MATCHES_RCVD, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mav.lukeshu.com From: Luke Shumaker To: libc-alpha@sourceware.org Cc: christian.brauner@mailbox.org Subject: [PATCH v6 4/6] linux ttyname and ttyname_r: Make the TTY equivalence checks consistent Date: Fri, 10 Nov 2017 15:08:25 -0500 Message-Id: <20171110200827.32265-5-lukeshu@lukeshu.com> In-Reply-To: <20171110200827.32265-1-lukeshu@lukeshu.com> References: <20171110200827.32265-1-lukeshu@lukeshu.com> From: Luke Shumaker In the ttyname and ttyname_r routines on Linux, at several points it needs to check if a given TTY is the TTY we are looking for. It used to be that this check was (to see if `maybe` is `mytty`): __xstat64(_STAT_VER, maybe_filename, &maybe) == 0 #ifdef _STATBUF_ST_RDEV && S_ISCHR(maybe.st_mode) && maybe.st_rdev == mytty.st_rdev #else && maybe.st_ino == mytty.st_ino && maybe.st_dev == mytty.st_dev #endif This check appears in several places. Then, one of the changes made in commit 15e9a4f378c8607c2ae1aa465436af4321db0e23 was to change that check to: __xstat64(_STAT_VER, maybe_filename, &maybe) == 0 #ifdef _STATBUF_ST_RDEV && S_ISCHR(maybe.st_mode) && maybe.st_rdev == mytty.st_rdev #endif && maybe.st_ino == mytty.st_ino && maybe.st_dev == mytty.st_dev That is, it made the st_ino and st_dev parts of the check happen even if we have the st_rdev member. This is an important change, because the kernel allows multiple devpts filesystem instances to be created; a device file in one devpts instance may share the same st_rdev with a file in another devpts instance, but they aren't the same file. This check appears twice in each file (ttyname.c and ttyname_r.c), once (in ttyname and __ttyname_r) to check if a candidate file found by inspecting /proc is the desired TTY, and once (in getttyname and getttyname_r) to check if a candidate file found by searching /dev is the desired TTY. However, 15e9a4f only updated the checks for files found via /proc; but the concern about collisions between devpts instances is just as valid for files found via /dev. So, update all 4 occurrences the check to be consistent with the version of the check introduced in 15e9a4f. Make it easy to keep all 4 occurrences of the check consistent by pulling it in to a static inline function, is_mytty. v2: - Rearrange commit order - Expand commit message - Reformat is_mytty - Have is_pty and is_mytty return bool instead of int - Specify 'const' on pointer arguments as necessary v3: - Revise commit message - Revise ChangeLog message - Split is_pty change into a separate commit - Fix whitespace style Reviewed-by: Christian Brauner --- ChangeLog | 7 +++++++ sysdeps/unix/sysv/linux/ttyname.c | 40 ++++++++---------------------------- sysdeps/unix/sysv/linux/ttyname.h | 12 +++++++++++ sysdeps/unix/sysv/linux/ttyname_r.c | 41 ++++++++----------------------------- 4 files changed, 36 insertions(+), 64 deletions(-) diff --git a/ChangeLog b/ChangeLog index 11709a01ac..f28c7c1afc 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,12 @@ 2017-11-07 Luke Shumaker + [BZ #22145] + * sysdeps/unix/sysv/linux/ttyname.h (is_mytty): New function. + * sysdeps/unix/sysv/linux/ttyname.c (getttyname): Call is_mytty. + (ttyname): Likewise. + * sysdeps/unix/sysv/linux/ttyname_r.c (getttyname_r): Likewise. + (__ttyname_r): Likewise. + * sysdeps/unix/sysv/linux/ttyname.h (is_pty): Change return type from int to bool. diff --git a/sysdeps/unix/sysv/linux/ttyname.c b/sysdeps/unix/sysv/linux/ttyname.c index 116cf350e5..6e97d2d455 100644 --- a/sysdeps/unix/sysv/linux/ttyname.c +++ b/sysdeps/unix/sysv/linux/ttyname.c @@ -35,14 +35,14 @@ char *__ttyname; #endif -static char *getttyname (const char *dev, dev_t mydev, - ino64_t myino, int save, int *dostat); +static char *getttyname (const char *dev, const struct stat64 *mytty, + int save, int *dostat); libc_freeres_ptr (static char *getttyname_name); static char * attribute_compat_text_section -getttyname (const char *dev, dev_t mydev, ino64_t myino, int save, int *dostat) +getttyname (const char *dev, const struct stat64 *mytty, int save, int *dostat) { static size_t namelen; struct stat64 st; @@ -63,7 +63,7 @@ getttyname (const char *dev, dev_t mydev, ino64_t myino, int save, int *dostat) *((char *) __mempcpy (getttyname_name, dev, devlen - 1)) = '/'; while ((d = __readdir64 (dirstream)) != NULL) - if ((d->d_fileno == myino || *dostat) + if ((d->d_fileno == mytty->st_ino || *dostat) && strcmp (d->d_name, "stdin") && strcmp (d->d_name, "stdout") && strcmp (d->d_name, "stderr")) @@ -85,12 +85,7 @@ getttyname (const char *dev, dev_t mydev, ino64_t myino, int save, int *dostat) } memcpy (&getttyname_name[devlen], d->d_name, dlen); if (__xstat64 (_STAT_VER, getttyname_name, &st) == 0 -#ifdef _STATBUF_ST_RDEV - && S_ISCHR (st.st_mode) && st.st_rdev == mydev -#else - && d->d_fileno == myino && st.st_dev == mydev -#endif - ) + && is_mytty (mytty, &st)) { (void) __closedir (dirstream); #if 0 @@ -167,12 +162,7 @@ ttyname (int fd) /* Verify readlink result, fall back on iterating through devices. */ if (ttyname_buf[0] == '/' && __xstat64 (_STAT_VER, ttyname_buf, &st1) == 0 -#ifdef _STATBUF_ST_RDEV - && S_ISCHR (st1.st_mode) - && st1.st_rdev == st.st_rdev -#endif - && st1.st_ino == st.st_ino - && st1.st_dev == st.st_dev) + && is_mytty (&st, &st1)) return ttyname_buf; /* If the link doesn't exist, then it points to a device in another @@ -186,11 +176,7 @@ ttyname (int fd) if (__xstat64 (_STAT_VER, "/dev/pts", &st1) == 0 && S_ISDIR (st1.st_mode)) { -#ifdef _STATBUF_ST_RDEV - name = getttyname ("/dev/pts", st.st_rdev, st.st_ino, save, &dostat); -#else - name = getttyname ("/dev/pts", st.st_dev, st.st_ino, save, &dostat); -#endif + name = getttyname ("/dev/pts", &st, save, &dostat); } else { @@ -200,21 +186,13 @@ ttyname (int fd) if (!name && dostat != -1) { -#ifdef _STATBUF_ST_RDEV - name = getttyname ("/dev", st.st_rdev, st.st_ino, save, &dostat); -#else - name = getttyname ("/dev", st.st_dev, st.st_ino, save, &dostat); -#endif + name = getttyname ("/dev", &st, save, &dostat); } if (!name && dostat != -1) { dostat = 1; -#ifdef _STATBUF_ST_RDEV - name = getttyname ("/dev", st.st_rdev, st.st_ino, save, &dostat); -#else - name = getttyname ("/dev", st.st_dev, st.st_ino, save, &dostat); -#endif + name = getttyname ("/dev", &st, save, &dostat); } return name; diff --git a/sysdeps/unix/sysv/linux/ttyname.h b/sysdeps/unix/sysv/linux/ttyname.h index ce4845a587..c290bfab36 100644 --- a/sysdeps/unix/sysv/linux/ttyname.h +++ b/sysdeps/unix/sysv/linux/ttyname.h @@ -33,3 +33,15 @@ is_pty (struct stat64 *sb) return false; #endif } + +static inline bool +is_mytty (const struct stat64 *mytty, const struct stat64 *maybe) +{ + return (maybe->st_ino == mytty->st_ino + && maybe->st_dev == mytty->st_dev +#ifdef _STATBUF_ST_RDEV + && S_ISCHR (maybe->st_mode) + && maybe->st_rdev == mytty->st_rdev +#endif + ); +} diff --git a/sysdeps/unix/sysv/linux/ttyname_r.c b/sysdeps/unix/sysv/linux/ttyname_r.c index 18f35ef2b7..58eb919c3f 100644 --- a/sysdeps/unix/sysv/linux/ttyname_r.c +++ b/sysdeps/unix/sysv/linux/ttyname_r.c @@ -31,12 +31,12 @@ #include "ttyname.h" static int getttyname_r (char *buf, size_t buflen, - dev_t mydev, ino64_t myino, int save, + const struct stat64 *mytty, int save, int *dostat); static int attribute_compat_text_section -getttyname_r (char *buf, size_t buflen, dev_t mydev, ino64_t myino, +getttyname_r (char *buf, size_t buflen, const struct stat64 *mytty, int save, int *dostat) { struct stat64 st; @@ -52,7 +52,7 @@ getttyname_r (char *buf, size_t buflen, dev_t mydev, ino64_t myino, } while ((d = __readdir64 (dirstream)) != NULL) - if ((d->d_fileno == myino || *dostat) + if ((d->d_fileno == mytty->st_ino || *dostat) && strcmp (d->d_name, "stdin") && strcmp (d->d_name, "stdout") && strcmp (d->d_name, "stderr")) @@ -72,12 +72,7 @@ getttyname_r (char *buf, size_t buflen, dev_t mydev, ino64_t myino, cp[0] = '\0'; if (__xstat64 (_STAT_VER, buf, &st) == 0 -#ifdef _STATBUF_ST_RDEV - && S_ISCHR (st.st_mode) && st.st_rdev == mydev -#else - && d->d_fileno == myino && st.st_dev == mydev -#endif - ) + && is_mytty (mytty, &st)) { (void) __closedir (dirstream); __set_errno (save); @@ -151,12 +146,7 @@ __ttyname_r (int fd, char *buf, size_t buflen) /* Verify readlink result, fall back on iterating through devices. */ if (buf[0] == '/' && __xstat64 (_STAT_VER, buf, &st1) == 0 -#ifdef _STATBUF_ST_RDEV - && S_ISCHR (st1.st_mode) - && st1.st_rdev == st.st_rdev -#endif - && st1.st_ino == st.st_ino - && st1.st_dev == st.st_dev) + && is_mytty (&st, &st1)) return 0; /* If the link doesn't exist, then it points to a device in another @@ -175,13 +165,8 @@ __ttyname_r (int fd, char *buf, size_t buflen) if (__xstat64 (_STAT_VER, buf, &st1) == 0 && S_ISDIR (st1.st_mode)) { -#ifdef _STATBUF_ST_RDEV - ret = getttyname_r (buf, buflen, st.st_rdev, st.st_ino, save, + ret = getttyname_r (buf, buflen, &st, save, &dostat); -#else - ret = getttyname_r (buf, buflen, st.st_dev, st.st_ino, save, - &dostat); -#endif } else { @@ -193,26 +178,16 @@ __ttyname_r (int fd, char *buf, size_t buflen) { buf[sizeof ("/dev/") - 1] = '\0'; buflen += sizeof ("pts/") - 1; -#ifdef _STATBUF_ST_RDEV - ret = getttyname_r (buf, buflen, st.st_rdev, st.st_ino, save, - &dostat); -#else - ret = getttyname_r (buf, buflen, st.st_dev, st.st_ino, save, + ret = getttyname_r (buf, buflen, &st, save, &dostat); -#endif } if (ret && dostat != -1) { buf[sizeof ("/dev/") - 1] = '\0'; dostat = 1; -#ifdef _STATBUF_ST_RDEV - ret = getttyname_r (buf, buflen, st.st_rdev, st.st_ino, - save, &dostat); -#else - ret = getttyname_r (buf, buflen, st.st_dev, st.st_ino, + ret = getttyname_r (buf, buflen, &st, save, &dostat); -#endif } return ret; From patchwork Fri Nov 10 20:08:26 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luke Shumaker X-Patchwork-Id: 836873 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=sourceware.org (client-ip=209.132.180.131; helo=sourceware.org; envelope-from=libc-alpha-return-86969-incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="lOt2EYpi"; dkim-atps=neutral Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yYWVq0TVDz9t3h for ; Sat, 11 Nov 2017 07:15:30 +1100 (AEDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; q=dns; s=default; b=tHMahWfIKqIQVhB6P3VEkAeEOHdbgVm xPqheigKv6o9so+OcgH1b3I9h+aELImISX1SKz4eLDPbyErpZsPwfXNTj3kBKWiR +f5CAcmo7KVcfYxriTO/UfQWya/sYGgAuXhOPb76XD2AL3fNzMtRK5zj2xGwzMMg 5Uk5E90Aa3nw= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; s=default; bh=KTazYgoQbSt1uK2G8t08/bymxlY=; b=lOt2E YpigRqIqPIxnZwcPEJ6K7shTBj3qhUx54/nmcyqJWqtBG31Gi8ynLB+iaYvc/+yQ HzsVN+YzPj8TSdNCWV3VLA3HlrCyPav0CByo552om9ypJOXRsNCTryYAeSMTZNEL iphKN7gshMox4KVxE4bR1UKpRSE6Nhd/xWoqlg= Received: (qmail 68982 invoked by alias); 10 Nov 2017 20:15:23 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 68874 invoked by uid 89); 10 Nov 2017 20:15:09 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RP_MATCHES_RCVD, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mav.lukeshu.com From: Luke Shumaker To: libc-alpha@sourceware.org Cc: christian.brauner@mailbox.org Subject: [PATCH v6 5/6] linux ttyname and ttyname_r: Don't bail prematurely [BZ #22145] Date: Fri, 10 Nov 2017 15:08:26 -0500 Message-Id: <20171110200827.32265-6-lukeshu@lukeshu.com> In-Reply-To: <20171110200827.32265-1-lukeshu@lukeshu.com> References: <20171110200827.32265-1-lukeshu@lukeshu.com> From: Luke Shumaker Commit 15e9a4f378c8607c2ae1aa465436af4321db0e23 introduced logic for ttyname() sending back ENODEV to signal that we can't get a name for the TTY because we inherited it from a different mount namespace. However, just because we inherited it from a different mount namespace and it isn't available at its original path, doesn't mean that its name is unknowable; we can still try to find it by allowing the normal fall back on iterating through devices. An example scenario where this happens is with "/dev/console" in containers. It's a common practice among container managers (including systemd-nspawn) to allocate a PTY master/slave pair in the host's mount namespace (the slave having a path like "/dev/pty/$X"), bind mount the slave to "/dev/console" in the container's mount namespace, and send the slave FD to a process in the container. Inside of the container, the slave-end isn't available at its original path ("/dev/pts/$X"), since the container mount namespace has a separate devpts instance from the host (that path may or may not exist in the container; if it does exist, it's not the same PTY slave device). Currently ttyname{_r} sees that the file at the original "/dev/pts/$X" path doesn't match the FD passed to it, and fails early and gives up, even though if it kept searching it would find the TTY at "/dev/console". Fix that; don't have the ENODEV path force an early return inhibiting the fall-back search. This change is based on the previous patch that adds use of is_mytty in getttyname and getttyname_r. Without that change, this effectively reverts 15e9a4f, which made us disregard the false similarity of file pointed to by "/proc/self/fd/$Y", because if it doesn't bail prematurely then that file ("/dev/pts/$X") will just come up again anyway in the fall-back search. v2: - Rearrange commit order - Revise commit message v3: - Revise commit message - Revise ChangeLog message - Fix style of block comments Reviewed-by: Christian Brauner --- ChangeLog | 5 +++++ sysdeps/unix/sysv/linux/ttyname.c | 19 ++++++++++++------- sysdeps/unix/sysv/linux/ttyname_r.c | 20 ++++++++++++-------- 3 files changed, 29 insertions(+), 15 deletions(-) diff --git a/ChangeLog b/ChangeLog index f28c7c1afc..9ea727499c 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,10 @@ 2017-11-07 Luke Shumaker + [BZ #22145] + * sysdeps/unix/sysv/linux/ttyname.c (ttyname): + Defer is_pty check until end of the function. + * sysdeps/unix/sysv/linux/ttyname_r.c (__ttyname_r): Likewise. + [BZ #22145] * sysdeps/unix/sysv/linux/ttyname.h (is_mytty): New function. * sysdeps/unix/sysv/linux/ttyname.c (getttyname): Call is_mytty. diff --git a/sysdeps/unix/sysv/linux/ttyname.c b/sysdeps/unix/sysv/linux/ttyname.c index 6e97d2d455..f4c955f25b 100644 --- a/sysdeps/unix/sysv/linux/ttyname.c +++ b/sysdeps/unix/sysv/linux/ttyname.c @@ -115,6 +115,7 @@ ttyname (int fd) char procname[30]; struct stat64 st, st1; int dostat = 0; + int doispty = 0; char *name; int save = errno; struct termios term; @@ -165,13 +166,7 @@ ttyname (int fd) && is_mytty (&st, &st1)) return ttyname_buf; - /* If the link doesn't exist, then it points to a device in another - namespace. */ - if (is_pty (&st)) - { - __set_errno (ENODEV); - return NULL; - } + doispty = 1; } if (__xstat64 (_STAT_VER, "/dev/pts", &st1) == 0 && S_ISDIR (st1.st_mode)) @@ -195,5 +190,15 @@ ttyname (int fd) name = getttyname ("/dev", &st, save, &dostat); } + if (!name && doispty && is_pty (&st)) + { + /* We failed to figure out the TTY's name, but we can at least + signal that we did verify that it really is a PTY slave. + This happens when we have inherited the file descriptor from + a different mount namespace. */ + __set_errno (ENODEV); + return NULL; + } + return name; } diff --git a/sysdeps/unix/sysv/linux/ttyname_r.c b/sysdeps/unix/sysv/linux/ttyname_r.c index 58eb919c3f..00eefc2c5c 100644 --- a/sysdeps/unix/sysv/linux/ttyname_r.c +++ b/sysdeps/unix/sysv/linux/ttyname_r.c @@ -95,6 +95,7 @@ __ttyname_r (int fd, char *buf, size_t buflen) char procname[30]; struct stat64 st, st1; int dostat = 0; + int doispty = 0; int save = errno; /* Test for the absolute minimal size. This makes life easier inside @@ -149,14 +150,7 @@ __ttyname_r (int fd, char *buf, size_t buflen) && is_mytty (&st, &st1)) return 0; - /* If the link doesn't exist, then it points to a device in another - * namespace. - */ - if (is_pty (&st)) - { - __set_errno (ENODEV); - return ENODEV; - } + doispty = 1; } /* Prepare the result buffer. */ @@ -190,6 +184,16 @@ __ttyname_r (int fd, char *buf, size_t buflen) save, &dostat); } + if (ret && doispty && is_pty (&st)) + { + /* We failed to figure out the TTY's name, but we can at least + signal that we did verify that it really is a PTY slave. + This happens when we have inherited the file descriptor from + a different mount namespace. */ + __set_errno (ENODEV); + return ENODEV; + } + return ret; } From patchwork Fri Nov 10 20:08:27 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luke Shumaker X-Patchwork-Id: 836866 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (mailfrom) smtp.mailfrom=sourceware.org (client-ip=209.132.180.131; helo=sourceware.org; envelope-from=libc-alpha-return-86968-incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.b="UKhPlt78"; dkim-atps=neutral Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yYWMq5FZNz9t3h for ; Sat, 11 Nov 2017 07:09:27 +1100 (AEDT) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; q=dns; s=default; b=BQH6pXV/RES6u8e5PtzEhNv8okeZWrN M5dEBGFdfWZXnjVRXcGuwgZfZYNOIl/VR+Gx2f24tujRHhNXmZzqHi7vSmpiTGDR 8rJR8ovxRY7RldDc2M9UMeI7dO/gy+pG3mHyTlMHnSegJ+Et6muta77XGU6pG/7F MHU6/Z+gkmwU= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:date:message-id:in-reply-to :references; s=default; bh=AGTQYkdFKICzDXEkKR/9jyWEcbA=; b=UKhPl t78rcwaOiTOmL7FRpynhOj8zjGk2AZqUaGGyq7i3smt1ri5cTSDHDTMHYIloOkhq GUVlc3oWhYtZ24Pg3uf93JsmDCJZw9BOga5RC6S3OQnnf+5d3aisifq+2KXAtMan Og1tyYONiPc6zDjSYYqUZx683mYa0daZNkIcmI= Received: (qmail 45012 invoked by alias); 10 Nov 2017 20:08:36 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 44839 invoked by uid 89); 10 Nov 2017 20:08:36 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-25.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, RP_MATCHES_RCVD, SEM_URIRED, SPF_HELO_PASS, SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mav.lukeshu.com From: Luke Shumaker To: libc-alpha@sourceware.org Cc: christian.brauner@mailbox.org Subject: [PATCH v6 6/6] linux ttyname and ttyname_r: Add tests Date: Fri, 10 Nov 2017 15:08:27 -0500 Message-Id: <20171110200827.32265-7-lukeshu@lukeshu.com> In-Reply-To: <20171110200827.32265-1-lukeshu@lukeshu.com> References: <20171110200827.32265-1-lukeshu@lukeshu.com> From: Luke Shumaker Add a new tst-ttyname test that includes several named sub-testcases. This patch is ordered after the patches with the fixes that it tests for (to avoid breaking `git bisect`), but for reference, here's how each relevant change so far affected the testcases in this commit, starting with 15e9a4f378c8607c2ae1aa465436af4321db0e23: | | before | | make checks | don't | | | 15e9a4f | 15e9a4f | consistent | bail | |---------------------------------+---------+---------+-------------+-------| | basic smoketest | PASS | PASS | PASS | PASS | | no conflict, no match | PASS[1] | PASS | PASS | PASS | | no conflict, console | PASS | FAIL! | FAIL | PASS! | | conflict, no match | FAIL | PASS! | PASS | PASS | | conflict, console | FAIL | FAIL | FAIL | PASS! | | with readlink target | PASS | PASS | PASS | PASS | | with readlink trap; fallback | FAIL | FAIL | FAIL | PASS! | | with readlink trap; no fallback | FAIL | PASS! | PASS | PASS | | with search-path trap | FAIL | FAIL | PASS! | PASS | |---------------------------------+---------+---------+-------------+-------| | | 4/9 | 5/9 | 6/9 | 9/9 | [1]: 15e9a4f introduced a semantic that, under certain failure conditions, ttyname sets errno=ENODEV, where previously it didn't set errno; it's not quite fair to hold "before 15e9a4f" ttyname to those new semantics. This testcase actually fails, but would have passed if we tested for the old the semantics. Each of the failing tests before 15e9a4f are all essentially the same bug: that it returns a PTY slave with the correct minor device number, but from the wrong devpts filesystem instance. 15e9a4f sought to fix this, but missed several of the cases that can cause this to happen, and also broke the case where both the erroneous PTY and the correct PTY exist. v2: - Rearrange commit order - Fix code style - Expand commit message - Pull xtouch, become-root, and chroot setup into functions - Better tracking of test failures - Fix the "with search-path trap" test case - Add test cases for the readlink target directly - More readable diagnostic output - Test with both shared and private procfs v3: - Revise commit message - Fix style of block comments v4: - Fix brace style - Clarify comments - Use if/else blocks instead of ternary operators - Say "if (!...) ok = false;" rather than "ok = ... && ok;" - Use xstrdup instead of strdup v5: - Avoid English idiom in a comment Acked-by: Christian Brauner --- ChangeLog | 4 + sysdeps/unix/sysv/linux/Makefile | 3 +- sysdeps/unix/sysv/linux/tst-ttyname.c | 625 ++++++++++++++++++++++++++++++++++ 3 files changed, 631 insertions(+), 1 deletion(-) create mode 100644 sysdeps/unix/sysv/linux/tst-ttyname.c diff --git a/ChangeLog b/ChangeLog index 9ea727499c..f677ef4d72 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,9 @@ 2017-11-07 Luke Shumaker + [BZ #22145] + * sysdeps/unix/sysv/linux/tst-ttyname.c: New file. + * sysdeps/unix/sysv/linux/Makefile: Add tst-ttyname to tests. + [BZ #22145] * sysdeps/unix/sysv/linux/ttyname.c (ttyname): Defer is_pty check until end of the function. diff --git a/sysdeps/unix/sysv/linux/Makefile b/sysdeps/unix/sysv/linux/Makefile index bf76b8773d..c6675b3aa5 100644 --- a/sysdeps/unix/sysv/linux/Makefile +++ b/sysdeps/unix/sysv/linux/Makefile @@ -43,7 +43,8 @@ sysdep_headers += sys/mount.h sys/acct.h sys/sysctl.h \ bits/siginfo-arch.h bits/siginfo-consts-arch.h tests += tst-clone tst-clone2 tst-clone3 tst-fanotify tst-personality \ - tst-quota tst-sync_file_range test-errno-linux tst-sysconf-iov_max + tst-quota tst-sync_file_range tst-sysconf-iov_max tst-ttyname \ + test-errno-linux # Generate the list of SYS_* macros for the system calls (__NR_* # macros). The file syscall-names.list contains all possible system diff --git a/sysdeps/unix/sysv/linux/tst-ttyname.c b/sysdeps/unix/sysv/linux/tst-ttyname.c new file mode 100644 index 0000000000..a5a4bb9689 --- /dev/null +++ b/sysdeps/unix/sysv/linux/tst-ttyname.c @@ -0,0 +1,625 @@ +/* Copyright (C) 2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation; either version 2.1 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; see the file COPYING.LIB. If + not, see . */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include + +/* generic utilities */ + +#define VERIFY(expr) \ + do { \ + if (!(expr)) \ + { \ + printf ("error: %s:%d: %s: %m\n", \ + __FILE__, __LINE__, #expr); \ + exit (1); \ + } \ + } while (0) + +static void +xtouch (const char *path, mode_t mode) +{ + xclose (xopen (path, O_WRONLY|O_CREAT|O_NOCTTY, mode)); +} + +static size_t +trim_prefix (char *str, size_t str_len, const char *prefix) +{ + size_t prefix_len = strlen (prefix); + if (str_len > prefix_len && memcmp (str, prefix, prefix_len) == 0) + { + memmove (str, str + prefix_len, str_len - prefix_len); + return str_len - prefix_len; + } + return str_len; +} + +/* returns a pointer to static storage */ +static char * +xreadlink (const char *linkname) +{ + static char target[PATH_MAX+1]; + ssize_t target_len = readlink (linkname, target, PATH_MAX); + VERIFY (target_len > 0); + target_len = trim_prefix (target, target_len, "(unreachable)"); + target[target_len] = '\0'; + return target; +} + +static void +become_root_in_mount_ns (void) +{ + uid_t orig_uid = getuid (); + gid_t orig_gid = getgid (); + + support_become_root (); + + if (unshare (CLONE_NEWNS) < 0) + FAIL_UNSUPPORTED ("could not enter new mount namespace"); + + /* support_become_root might have put us in a new user namespace; + most filesystems (including tmpfs) don't allow file or directory + creation from a user namespace unless uid and gid maps are set, + even if we have root privileges in the namespace (failing with + EOVERFLOW, since the uid overflows the empty (0-length) uid map). + + Also, stat always reports that uid and gid maps are empty, so we + have to try actually reading from them to check if they are + empty. */ + int fd; + + if ((fd = open ("/proc/self/uid_map", O_RDWR, 0)) >= 0) + { + char buf; + if (read (fd, &buf, 1) == 0) + { + char *str = xasprintf ("0 %ld 1\n", (long)orig_uid); + if (write (fd, str, strlen (str)) < 0) + FAIL_EXIT1 ("write (uid_map, \"%s\"): %m", str); + free (str); + } + xclose (fd); + } + + /* Setting the gid map has the additional complexity that we have to + first turn off setgroups. */ + if ((fd = open ("/proc/self/setgroups", O_WRONLY, 0)) >= 0) + { + const char *str = "deny"; + if (write (fd, str, strlen (str)) < 0) + FAIL_EXIT1 ("write (setroups, \"%s\"): %m", str); + xclose (fd); + } + + if ((fd = open ("/proc/self/gid_map", O_RDWR, 0)) >= 0) + { + char buf; + if (read (fd, &buf, 1) == 0) + { + char *str = xasprintf ("0 %ld 1\n", (long)orig_gid); + if (write (fd, str, strlen (str)) < 0) + FAIL_EXIT1 ("write (gid_map, \"%s\"): %m", str); + free (str); + } + xclose (fd); + } +} + +/* plain ttyname runner */ + +struct result +{ + const char *name; + int err; +}; + +/* strings in result structure are in static storage */ +static struct result +run_ttyname (int fd) +{ + struct result ret; + errno = 0; + ret.name = ttyname (fd); + ret.err = errno; + return ret; +} + +static bool +eq_ttyname (struct result actual, struct result expected) +{ + char *actual_name, *expected_name; + + if ((actual.err == expected.err) && + (!actual.name == !expected.name) && + (actual.name ? strcmp (actual.name, expected.name) == 0 : true)) + { + if (expected.name) + expected_name = xasprintf ("\"%s\"", expected.name); + else + expected_name = xstrdup ("NULL"); + + printf ("info: ttyname: PASS {name=%s, errno=%d}\n", + expected_name, expected.err); + + free (expected_name); + return true; + } + + if (actual.name) + actual_name = xasprintf ("\"%s\"", actual.name); + else + actual_name = xstrdup ("NULL"); + + if (expected.name) + expected_name = xasprintf ("\"%s\"", expected.name); + else + expected_name = xstrdup ("NULL"); + + printf ("error: ttyname: actual {name=%s, errno=%d} != expected {name=%s, errno=%d}\n", + actual_name, actual.err, + expected_name, expected.err); + + free (actual_name); + free (expected_name); + return false; +} + +/* ttyname_r runner */ + +struct result_r +{ + const char *name; + int ret; + int err; +}; + +/* strings in result structure are in static storage */ +static struct result_r +run_ttyname_r (int fd) +{ + static char buf[TTY_NAME_MAX]; + + struct result_r ret; + errno = 0; + ret.ret = ttyname_r (fd, buf, TTY_NAME_MAX); + ret.err = errno; + if (ret.ret == 0) + ret.name = buf; + else + ret.name = NULL; + return ret; +} + +static bool +eq_ttyname_r (struct result_r actual, struct result_r expected) +{ + char *actual_name, *expected_name; + + if ((actual.err == expected.err) && + (actual.ret == expected.ret) && + (!actual.name == !expected.name) && + (actual.name ? strcmp (actual.name, expected.name) == 0 : true)) + { + if (expected.name) + expected_name = xasprintf ("\"%s\"", expected.name); + else + expected_name = xstrdup ("NULL"); + + printf ("info: ttyname_r: PASS {name=%s, ret=%d, errno=%d}\n", + expected_name, expected.ret, expected.err); + + free (expected_name); + return true; + } + + if (actual.name) + actual_name = xasprintf ("\"%s\"", actual.name); + else + actual_name = xstrdup ("NULL"); + + if (expected.name) + expected_name = xasprintf ("\"%s\"", expected.name); + else + expected_name = xstrdup ("NULL"); + + printf ("error: ttyname_r: actual {name=%s, ret=%d, errno=%d} != expected {name=%s, ret=%d, errno=%d}\n", + actual_name, actual.ret, actual.err, + expected_name, expected.ret, expected.err); + + free (actual_name); + free (expected_name); + return false; +} + +/* combined runner */ + +static bool +doit (int fd, const char *testname, struct result_r expected_r) +{ + struct result expected = {.name=expected_r.name, .err=expected_r.ret}; + bool ret = true; + + printf ("info: testcase: %s\n", testname); + + if (!eq_ttyname (run_ttyname (fd), expected)) + ret = false; + if (!eq_ttyname_r (run_ttyname_r (fd), expected_r)) + ret = false; + + if (!ret) + support_record_failure (); + + return ret; +} + +/* chroot setup */ + +static char *chrootdir; + +static void +prepare (int argc, char **argv) +{ + chrootdir = xasprintf ("%s/tst-ttyname-XXXXXX", test_dir); + if (mkdtemp (chrootdir) == NULL) + FAIL_EXIT1 ("mkdtemp (\"%s\"): %m", chrootdir); + add_temp_file (chrootdir); +} +#define PREPARE prepare + +/* These chroot setup functions put the TTY at at "/console" (where it + won't be found by ttyname), and create "/dev/console" as an + ordinary file. This way, it's easier to write test-cases that + expect ttyname to fail; test-cases that expect it to succeed need + to explicitly remount it at "/dev/console". */ + +static int +do_in_chroot_1 (int (*cb)(const char *, int)) +{ + printf ("info: entering chroot 1\n"); + + /* Open the PTS that we'll be testing on. */ + int master; + char *slavename; + VERIFY ((master = posix_openpt (O_RDWR|O_NOCTTY|O_NONBLOCK)) >= 0); + VERIFY ((slavename = ptsname (master))); + VERIFY (unlockpt (master) == 0); + if (strncmp (slavename, "/dev/pts/", 9) != 0) + FAIL_UNSUPPORTED ("slave pseudo-terminal is not under /dev/pts/: %s", + slavename); + int slave = xopen (slavename, O_RDWR, 0); + if (!doit (slave, "basic smoketest", + (struct result_r){.name=slavename, .ret=0, .err=0})) + return 1; + + pid_t pid = xfork (); + if (pid == 0) + { + xclose (master); + + become_root_in_mount_ns (); + + VERIFY (mount ("tmpfs", chrootdir, "tmpfs", 0, "mode=755") == 0); + VERIFY (chdir (chrootdir) == 0); + + xmkdir ("proc", 0755); + xmkdir ("dev", 0755); + xmkdir ("dev/pts", 0755); + + VERIFY (mount ("/proc", "proc", NULL, MS_BIND|MS_REC, NULL) == 0); + VERIFY (mount ("devpts", "dev/pts", "devpts", + MS_NOSUID|MS_NOEXEC, + "newinstance,ptmxmode=0666,mode=620") == 0); + VERIFY (symlink ("pts/ptmx", "dev/ptmx") == 0); + + xtouch ("console", 0); + xtouch ("dev/console", 0); + VERIFY (mount (slavename, "console", NULL, MS_BIND, NULL) == 0); + + xchroot ("."); + + char *linkname = xasprintf ("/proc/self/fd/%d", slave); + char *target = xreadlink (linkname); + VERIFY (strcmp (target, slavename) == 0); + free (linkname); + + _exit (cb (slavename, slave)); + } + int status; + xwaitpid (pid, &status, 0); + VERIFY (WIFEXITED (status)); + xclose (master); + xclose (slave); + return WEXITSTATUS (status); +} + +static int +do_in_chroot_2 (int (*cb)(const char *, int)) +{ + printf ("info: entering chroot 2\n"); + + int pid_pipe[2]; + xpipe (pid_pipe); + int exit_pipe[2]; + xpipe (exit_pipe); + + /* Open the PTS that we'll be testing on. */ + int master; + char *slavename; + VERIFY ((master = posix_openpt (O_RDWR|O_NOCTTY|O_NONBLOCK)) >= 0); + VERIFY ((slavename = ptsname (master))); + VERIFY (unlockpt (master) == 0); + if (strncmp (slavename, "/dev/pts/", 9) != 0) + FAIL_UNSUPPORTED ("slave pseudo-terminal is not under /dev/pts/: %s", + slavename); + /* wait until in a new mount ns to open the slave */ + + /* enable `wait`ing on grandchildren */ + VERIFY (prctl (PR_SET_CHILD_SUBREAPER, 1) == 0); + + pid_t pid = xfork (); /* outer child */ + if (pid == 0) + { + xclose (master); + xclose (pid_pipe[0]); + xclose (exit_pipe[1]); + + become_root_in_mount_ns (); + + int slave = xopen (slavename, O_RDWR, 0); + if (!doit (slave, "basic smoketest", + (struct result_r){.name=slavename, .ret=0, .err=0})) + _exit (1); + + VERIFY (mount ("tmpfs", chrootdir, "tmpfs", 0, "mode=755") == 0); + VERIFY (chdir (chrootdir) == 0); + + xmkdir ("proc", 0755); + xmkdir ("dev", 0755); + xmkdir ("dev/pts", 0755); + + VERIFY (mount ("devpts", "dev/pts", "devpts", + MS_NOSUID|MS_NOEXEC, + "newinstance,ptmxmode=0666,mode=620") == 0); + VERIFY (symlink ("pts/ptmx", "dev/ptmx") == 0); + + xtouch ("console", 0); + xtouch ("dev/console", 0); + VERIFY (mount (slavename, "console", NULL, MS_BIND, NULL) == 0); + + xchroot ("."); + + if (unshare (CLONE_NEWNS | CLONE_NEWPID) < 0) + FAIL_UNSUPPORTED ("could not enter new PID namespace"); + pid = xfork (); /* inner child */ + if (pid == 0) + { + xclose (pid_pipe[1]); + + /* wait until the outer child has exited */ + char c; + VERIFY (read (exit_pipe[0], &c, 1) == 0); + xclose (exit_pipe[0]); + + VERIFY (mount ("proc", "/proc", "proc", + MS_NOSUID|MS_NOEXEC|MS_NODEV, NULL) == 0); + + char *linkname = xasprintf ("/proc/self/fd/%d", slave); + char *target = xreadlink (linkname); + VERIFY (strcmp (target, strrchr (slavename, '/')) == 0); + free (linkname); + + _exit (cb (slavename, slave)); + } + xwrite (pid_pipe[1], &pid, sizeof pid); + _exit (0); + } + xclose (pid_pipe[1]); + xclose (exit_pipe[0]); + xclose (exit_pipe[1]); + + /* wait for the outer child */ + int status; + xwaitpid (pid, &status, 0); + VERIFY (WIFEXITED (status)); + int ret = WEXITSTATUS (status); + if (ret != 0) + return ret; + + /* set 'pid' to the inner child */ + VERIFY (read (pid_pipe[0], &pid, sizeof pid) == sizeof pid); + xclose (pid_pipe[0]); + + /* wait for the inner child */ + xwaitpid (pid, &status, 0); + VERIFY (WIFEXITED (status)); + xclose (master); + return WEXITSTATUS (status); +} + +/* main test */ + +static int +run_chroot_tests (const char *slavename, int slave) +{ + struct stat st; + bool ok = true; + + /* There are 3 groups of tests here. The first group fairly + generically does things known to mess up ttyname, and verifies + that ttyname copes correctly. The remaining groups are + increasingly convoluted, as we target specific parts of ttyname + to try to confuse. */ + + /* Basic tests that it doesn't get confused by multiple devpts + instances. */ + { + VERIFY (stat (slavename, &st) < 0); /* sanity check */ + if (!doit (slave, "no conflict, no match", + (struct result_r){.name=NULL, .ret=ENODEV, .err=ENODEV})) + ok = false; + VERIFY (mount ("/console", "/dev/console", NULL, MS_BIND, NULL) == 0); + if (!doit (slave, "no conflict, console", + (struct result_r){.name="/dev/console", .ret=0, .err=0})) + ok = false; + VERIFY (umount ("/dev/console") == 0); + + /* keep creating PTYs until we we get a name collision */ + while (stat (slavename, &st) < 0) + posix_openpt (O_RDWR|O_NOCTTY|O_NONBLOCK); + VERIFY (stat (slavename, &st) == 0); + + if (!doit (slave, "conflict, no match", + (struct result_r){.name=NULL, .ret=ENODEV, .err=ENODEV})) + ok = false; + VERIFY (mount ("/console", "/dev/console", NULL, MS_BIND, NULL) == 0); + if (!doit (slave, "conflict, console", + (struct result_r){.name="/dev/console", .ret=0, .err=0})) + ok = false; + VERIFY (umount ("/dev/console") == 0); + } + + /* The first tests kinda assumed that they hit certain code-paths + based on assuming that the readlink target is 'slavename', but + that's not quite always true. They're still a good preliminary + sanity check, so keep them, but let's add tests that make sure + that those code-paths are hit by doing a readlink ourself. */ + { + char *linkname = xasprintf ("/proc/self/fd/%d", slave); + char *target = xreadlink (linkname); + free (linkname); + /* Depeding on how we set up the chroot, the kernel may or may not + trim the leading path to the target (it may give us "/6", + instead of "/dev/pts/6"). We test it both ways (do_in_chroot_1 + and do_in_chroot_2). This test group relies on the target + existing, so guarantee that it does exist by creating it if + necessary. */ + if (stat (target, &st) < 0) + { + VERIFY (errno == ENOENT); + xtouch (target, 0); + } + + VERIFY (mount ("/console", "/dev/console", NULL, MS_BIND, NULL) == 0); + VERIFY (mount ("/console", target, NULL, MS_BIND, NULL) == 0); + if (!doit (slave, "with readlink target", + (struct result_r){.name=target, .ret=0, .err=0})) + ok = false; + VERIFY (umount (target) == 0); + VERIFY (umount ("/dev/console") == 0); + + VERIFY (mount ("/console", "/dev/console", NULL, MS_BIND, NULL) == 0); + VERIFY (mount (slavename, target, NULL, MS_BIND, NULL) == 0); + if (!doit (slave, "with readlink trap; fallback", + (struct result_r){.name="/dev/console", .ret=0, .err=0})) + ok = false; + VERIFY (umount (target) == 0); + VERIFY (umount ("/dev/console") == 0); + + VERIFY (mount (slavename, target, NULL, MS_BIND, NULL) == 0); + if (!doit (slave, "with readlink trap; no fallback", + (struct result_r){.name=NULL, .ret=ENODEV, .err=ENODEV})) + ok = false; + VERIFY (umount (target) == 0); + } + + /* This test makes sure that everything still works OK if readdir + finds a pseudo-match before and/or after the actual match. Now, + to do that, we need to control that readdir finds the + pseudo-matches before and after the actual match; and there's no + good way to control that order in absence of whitebox testing. + So, just create 3 files, then use opendir/readdir to see what + order they are in, and assign meaning based on that order, not by + name; assigning the first to be a pseudo-match, the second to be + the actual match, and the third to be a pseudo-match. This + assumes that (on tmpfs) ordering within the directory is stable + in the absence of modification, which seems reasonably safe. */ + { + /* since we're testing the fallback search, disable the readlink + happy-path */ + VERIFY (umount2 ("/proc", MNT_DETACH) == 0); + + xtouch ("/dev/console1", 0); + xtouch ("/dev/console2", 0); + xtouch ("/dev/console3", 0); + + char *c[3]; + int ci = 0; + DIR *dirstream = opendir ("/dev"); + VERIFY (dirstream != NULL); + struct dirent *d; + while ((d = readdir (dirstream)) != NULL && ci < 3) + { + if (strcmp (d->d_name, "console1") && + strcmp (d->d_name, "console2") && + strcmp (d->d_name, "console3") ) + continue; + c[ci++] = xasprintf ("/dev/%s", d->d_name); + } + VERIFY (ci == 3); + VERIFY (closedir (dirstream) == 0); + + VERIFY (mount (slavename, c[0], NULL, MS_BIND, NULL) == 0); + VERIFY (mount ("/console", c[1], NULL, MS_BIND, NULL) == 0); + VERIFY (mount (slavename, c[2], NULL, MS_BIND, NULL) == 0); + VERIFY (umount2 ("/dev/pts", MNT_DETACH) == 0); + if (!doit (slave, "with search-path trap", + (struct result_r){.name=c[1], .ret=0, .err=0})) + ok = false; + for (int i = 0; i < 3; i++) + { + VERIFY (umount (c[i]) == 0); + VERIFY (unlink (c[i]) == 0); + free (c[i]); + } + } + + return ok ? 0 : 1; +} + +static int +do_test (void) +{ + int ret1 = do_in_chroot_1 (run_chroot_tests); + if (ret1 == EXIT_UNSUPPORTED) + return ret1; + + int ret2 = do_in_chroot_2 (run_chroot_tests); + if (ret2 == EXIT_UNSUPPORTED) + return ret2; + + return ret1 | ret2; +} + +#include