platform_bionic/libc/bionic/fcntl.cpp
Elliott Hughes 1e59e2a88d fcntl: remove some duplication, fix a bug.
Treehugger didn't test 32-bit (and neither, of course, had I), so we
didn't notice until the next day that I'd only added the new check to
the 64-bit codepath. Let's just unify the two, since there's only one
line of meaningful difference.

Bug: http://b/261092827
Test: treehugger
Change-Id: I5178257a76fe24a340b3659c85ad29ed0a7b8b50
2022-12-02 02:56:50 +00:00

62 lines
2.4 KiB
C++

/*
* Copyright (C) 2019 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <stdarg.h>
#include <fcntl.h>
#include "private/bionic_fdtrack.h"
#include "private/bionic_fortify.h"
extern "C" int __fcntl(int fd, int cmd, ...);
extern "C" int __fcntl64(int, int, ...);
int fcntl(int fd, int cmd, ...) {
va_list args;
va_start(args, cmd);
// This is a bit sketchy for LP64, especially because arg can be an int,
// but all of our supported 64-bit ABIs pass the argument in a register.
void* arg = va_arg(args, void*);
va_end(args);
if (cmd == F_SETFD && (reinterpret_cast<uintptr_t>(arg) & ~FD_CLOEXEC) != 0) {
__fortify_fatal("fcntl(F_SETFD) passed non-FD_CLOEXEC flag: %p", arg);
}
#if defined(__LP64__)
int rc = __fcntl(fd, cmd, arg);
#else
// For LP32 we use the fcntl64 system call to signal that we're using struct flock64.
int rc = __fcntl64(fd, cmd, arg);
#endif
if (cmd == F_DUPFD) {
return FDTRACK_CREATE_NAME("F_DUPFD", rc);
} else if (cmd == F_DUPFD_CLOEXEC) {
return FDTRACK_CREATE_NAME("F_DUPFD_CLOEXEC", rc);
}
return rc;
}