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Luke Shumaker 2fbce9c203
linux ttyname{_r}: Make tty checks consistent
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 15e9a4f378
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.

Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
2017-11-15 20:47:07 +01:00
argp Mark internal argp functions with attribute_hidden [BZ #18822] 2017-10-01 15:10:27 -07:00
assert Fix position of tests-unsupported definition in assert/Makefile. 2017-08-22 00:30:51 +00:00
benchtests Benchtests for sinf, cosf and sincosf 2017-10-13 14:19:45 +05:30
bits Move <bits/mman-linux.h> to the Linux sysdeps directory 2017-11-07 12:11:42 +01:00
catgets Don't compile non-lib modules as lib modules [BZ #21864] 2017-08-21 05:34:54 -07:00
ChangeLog.old Add missing reference to bug 21654 2017-10-07 13:14:36 +02:00
conform Fix mcontext_t sigcontext namespace (bug 21457). 2017-08-30 22:02:04 +00:00
crypt crypt: Use NSPR header files in addition to NSS header files [BZ #17956] 2017-10-04 15:02:35 +02:00
csu Use newly built crt*.o files to build shared objects [BZ #22362] 2017-11-06 08:29:57 -08:00
ctype Use locale_t, not __locale_t, throughout glibc 2017-06-20 20:30:06 -04:00
debug Enable unwind info in libc-start.c and backtrace.c 2017-09-19 15:07:58 +01:00
dev Rename xlocale.h to bits/types/__locale_t.h. 2017-06-20 20:28:11 -04:00
dirent hurd: Fix dirfd symbol exposition from ftw 2017-09-28 00:49:05 +02:00
dlfcn Mark __dso_handle as hidden [BZ #18822] 2017-09-26 16:53:44 -07:00
elf ld.so: Add architecture specific fields 2017-11-13 08:02:52 -08:00
gmon Add a test for profiling static executable 2017-10-14 12:58:55 -07:00
gnulib Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
grp Remove compat from DEFAULT_CONFIG lookup strings 2017-09-12 10:21:48 -07:00
gshadow Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
hesiod Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
hurd hurd: fix gethostname(NULL, 0) 2017-09-07 00:51:17 +02:00
iconv localedef: Add --no-warnings/--warnings option 2017-10-25 13:36:54 -07:00
iconvdata Add new codepage charmaps/IBM858 [BZ #21084] 2017-09-14 15:50:57 +02:00
include ld.so: Add architecture specific fields 2017-11-13 08:02:52 -08:00
inet Hide internal idna functions [BZ #18822] 2017-10-01 17:33:22 -07:00
intl Hide internal __hash_string function [BZ #18822] 2017-10-01 17:41:34 -07:00
io Assume that _DIRENT_HAVE_D_TYPE is always defined. 2017-10-30 15:48:33 +01:00
libidn Remove add-ons mechanism. 2017-10-05 15:58:13 +00:00
libio Always do locking when iterating over list of streams (bug 15142) 2017-10-05 17:26:05 +02:00
locale Assume that _DIRENT_HAVE_D_TYPE is always defined. 2017-10-30 15:48:33 +01:00
localedata ka_GE locale: Add “X” back to yesexpr. 2017-11-15 13:23:13 +01:00
login openpty: use TIOCGPTPEER to open slave side fd 2017-10-08 17:47:58 +02:00
mach hurd: Remove duplicate symbol version 2017-08-28 14:19:55 +02:00
malloc malloc: Account for all heaps in an arena in malloc_info [BZ #22439] 2017-11-15 11:40:41 +01:00
manual manual: Update to mention ENODEV for ttyname and ttyname_r 2017-11-15 20:46:45 +01:00
math Use __builtin_tgmath in tgmath.h with GCC 8 (bug 21660). 2017-11-15 02:08:56 +00:00
mathvec Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
misc Hide internal __hasmntopt function [BZ #18822] 2017-10-01 17:37:42 -07:00
nis nscd: remove reference to libnsl 2017-10-11 15:51:52 +02:00
nptl Remove traces of tst-typesizes 2017-11-07 16:17:18 +01:00
nptl_db Move all old ChangeLogs to a top-level ChangeLog.old directory. 2017-09-01 09:31:43 -04:00
nscd nscd: remove reference to libnsl 2017-10-11 15:51:52 +02:00
nss nss_files: Avoid large buffers with many host addresses [BZ #22078] 2017-10-11 07:07:51 +02:00
po Update translations from the Translation Project 2017-11-03 23:30:23 +00:00
posix posix/tst-glob-tilde.c: Add test for bug 22332 2017-11-02 11:06:45 +01:00
pwd Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
resolv support: Add <support/next_to_fault.h> 2017-11-13 19:29:32 +01:00
resource Hide internal __setrlimit function [BZ #18822] 2017-10-01 17:46:54 -07:00
rt aio: Remove internal_function function attribute 2017-08-31 15:59:06 +02:00
scripts Use Linux 4.14 in build-many-glibcs.py. 2017-11-15 17:10:03 +00:00
setjmp Remove __need macros from signal.h. 2017-05-20 19:04:43 -04:00
shadow Remove __need macros from stdio.h and wchar.h. 2017-06-08 13:58:17 -04:00
signal Optimize sigrelse implementation 2017-11-15 15:45:39 -02:00
socket __opensock: Remove internal_function attribute 2017-08-17 10:18:15 +02:00
soft-fp Use libm_alias_* in soft-fp. 2017-10-11 00:03:46 +00:00
stdio-common stdio-common: Use array_length and array_end macros 2017-11-02 12:45:20 +01:00
stdlib Handle more _FloatN, _FloatNx types in type-generic strtod tests. 2017-11-07 18:08:44 +00:00
streams Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
string Fix string/tester.c build with GCC 8. 2017-11-14 17:52:26 +00:00
sunrpc sunrpc/tst-udp-nonblocking: Fix timeout value 2017-09-10 21:09:28 +02:00
support support: Add <support/next_to_fault.h> 2017-11-13 19:29:32 +01:00
sysdeps linux ttyname{_r}: Make tty checks consistent 2017-11-15 20:47:07 +01:00
sysvipc Fix test-sysvsem on some platforms 2017-01-02 18:53:50 -02:00
termios Hide internal __tcgetattr function [BZ #18822] 2017-10-01 17:48:24 -07:00
time time: Remove the internal_function attribute 2017-08-31 15:59:07 +02:00
timezone timezone: pacify GCC -Wstringop-truncation 2017-11-12 22:00:28 -08:00
wcsmbs Declare wcstof functions for more _FloatN, _FloatNx types. 2017-11-02 23:36:00 +00:00
wctype Use locale_t, not __locale_t, throughout glibc 2017-06-20 20:30:06 -04:00
.gitattributes Assume __NR_openat is always defined 2016-03-23 23:35:08 +01:00
.gitignore Add *.pyc to .gitignore 2015-05-18 15:26:26 +05:30
abi-tags Remove the bulk of the NaCl port. 2017-05-20 08:09:10 -04:00
aclocal.m4 gmon: Add test for basic mcount/gprof functionality 2017-08-15 15:49:45 +02:00
ChangeLog linux ttyname{_r}: Make tty checks consistent 2017-11-15 20:47:07 +01:00
config.h.in Don't use hidden visibility in libc.a with PIE on i386 2017-10-04 17:18:42 -07:00
config.make.in Use newly built crt*.o files to build shared objects [BZ #22362] 2017-11-06 08:29:57 -08:00
configure Use newly built crt*.o files to build shared objects [BZ #22362] 2017-11-06 08:29:57 -08:00
configure.ac Use newly built crt*.o files to build shared objects [BZ #22362] 2017-11-06 08:29:57 -08:00
COPYING Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
COPYING.LIB Update to latest versions of GPL-2.0 and LGPL-2.1 2013-09-09 12:52:48 +10:00
extra-lib.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
gen-locales.mk Split locale generation snippet into a separate file 2015-05-13 13:05:28 +05:30
INSTALL Remove add-ons mechanism. 2017-10-05 15:58:13 +00:00
libc-abis A few more archs have IFUNC support. 2010-03-17 02:43:12 -07:00
libof-iterator.mk Rename cppflags-iterator.mk to libof-iterator.mk, remove extra-modules.mk. 2017-05-09 07:06:29 -04:00
LICENSES Expand LICENSES file. 2012-12-05 21:56:15 +00:00
MAINTAINERS Add MAINTAINERS 2017-05-11 13:38:30 -04:00
Makeconfig Add a test for profiling static executable 2017-10-14 12:58:55 -07:00
Makefile Remove add-ons mechanism. 2017-10-05 15:58:13 +00:00
Makefile.in New make target to only build benchmark binaries 2016-04-20 10:23:28 +05:30
Makerules Use newly built crt*.o files to build shared objects [BZ #22362] 2017-11-06 08:29:57 -08:00
NEWS malloc: Account for all heaps in an arena in malloc_info [BZ #22439] 2017-11-15 11:40:41 +01:00
o-iterator.mk
README Require Linux kernel 3.2 or later on x86 / x86_64. 2017-05-08 10:45:20 +00:00
Rules Suppress internal declarations for most of the testsuite. 2017-05-11 19:27:59 -04:00
shlib-versions Extend NSS test suite 2017-07-17 15:52:44 -04:00
test-skeleton.c Update copyright dates with scripts/update-copyrights. 2017-01-01 00:14:16 +00:00
version.h version.h: Switch to ".9000" as the suffix for the development version 2017-10-16 21:39:18 +02:00

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