From 65f6f938cd562a614a68e15d0581a34b177ec29d Mon Sep 17 00:00:00 2001 From: Eric Rannaud Date: Tue, 24 Feb 2015 13:12:26 +0530 Subject: linux: open and openat ignore 'mode' with O_TMPFILE in flags Both open and openat load their last argument 'mode' lazily, using va_arg() only if O_CREAT is found in oflag. This is wrong, mode is also necessary if O_TMPFILE is in oflag. By chance on x86_64, the problem wasn't evident when using O_TMPFILE with open, as the 3rd argument of open, even when not loaded with va_arg, is left untouched in RDX, where the syscall expects it. However, openat was not so lucky, and O_TMPFILE couldn't be used: mode is the 4th argument, in RCX, but the syscall expects its 4th argument in a different register than the glibc wrapper, in R10. Introduce a macro __OPEN_NEEDS_MODE (oflag) to test if either O_CREAT or O_TMPFILE is set in oflag. Tested on Linux x86_64. [BZ #17523] * io/fcntl.h (__OPEN_NEEDS_MODE): New macro. * io/bits/fcntl2.h (open): Use it. (openat): Likewise. * io/open.c (__libc_open): Likewise. * io/open64.c (__libc_open64): Likewise. * io/open64_2.c (__open64_2): Likewise. * io/open_2.c (__open_2): Likewise. * io/openat.c (__openat): Likewise. * io/openat64.c (__openat64): Likewise. * io/openat64_2.c (__openat64_2): Likewise. * io/openat_2.c (__openat_2): Likewise. * sysdeps/mach/hurd/open.c (__libc_open): Likewise. * sysdeps/mach/hurd/openat.c (__openat): Likewise. * sysdeps/posix/open64.c (__libc_open64): Likewise. * sysdeps/unix/sysv/linux/dl-openat64.c (openat64): Likewise. * sysdeps/unix/sysv/linux/generic/open.c (__libc_open): Likewise. (__open_nocancel): Likewise. * sysdeps/unix/sysv/linux/generic/open64.c (__libc_open64): Likewise. * sysdeps/unix/sysv/linux/open64.c (__libc_open64): Likewise. * sysdeps/unix/sysv/linux/openat.c (__OPENAT): Likewise. --- sysdeps/unix/sysv/linux/openat.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'sysdeps/unix/sysv/linux/openat.c') diff --git a/sysdeps/unix/sysv/linux/openat.c b/sysdeps/unix/sysv/linux/openat.c index 5145823b8e..30d8e6e1ac 100644 --- a/sysdeps/unix/sysv/linux/openat.c +++ b/sysdeps/unix/sysv/linux/openat.c @@ -54,13 +54,13 @@ OPENAT_NOT_CANCEL (int fd, const char *file, int oflag, mode_t mode) /* Open FILE with access OFLAG. Interpret relative paths relative to - the directory associated with FD. If OFLAG includes O_CREAT, a - third argument is the file protection. */ + the directory associated with FD. If OFLAG includes O_CREAT or + O_TMPFILE, a fourth argument is the file protection. */ int __OPENAT (int fd, const char *file, int oflag, ...) { mode_t mode = 0; - if (oflag & O_CREAT) + if (__OPEN_NEEDS_MODE (oflag)) { va_list arg; va_start (arg, oflag); -- cgit 1.4.1