From e7e1c875b0f8eefb1d771f200a58f54e64c39d55 Mon Sep 17 00:00:00 2001 From: Daniel Micay Date: Thu, 16 Apr 2015 09:07:45 -0400 Subject: add fortified implementations of pread/pread64 Change-Id: Iec39c3917e0bc94371bd81541619392f5abe29b9 --- libc/Android.mk | 2 ++ libc/bionic/__pread64_chk.cpp | 43 +++++++++++++++++++++++++++ libc/bionic/__pread_chk.cpp | 43 +++++++++++++++++++++++++++ libc/include/unistd.h | 67 +++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 155 insertions(+) create mode 100644 libc/bionic/__pread64_chk.cpp create mode 100644 libc/bionic/__pread_chk.cpp (limited to 'libc') diff --git a/libc/Android.mk b/libc/Android.mk index e06a860..9d3b62a 100644 --- a/libc/Android.mk +++ b/libc/Android.mk @@ -71,6 +71,8 @@ libc_common_src_files += \ bionic/__fgets_chk.cpp \ bionic/__memmove_chk.cpp \ bionic/__poll_chk.cpp \ + bionic/__pread64_chk.cpp \ + bionic/__pread_chk.cpp \ bionic/__read_chk.cpp \ bionic/__recvfrom_chk.cpp \ bionic/__stpcpy_chk.cpp \ diff --git a/libc/bionic/__pread64_chk.cpp b/libc/bionic/__pread64_chk.cpp new file mode 100644 index 0000000..5d6ad2d --- /dev/null +++ b/libc/bionic/__pread64_chk.cpp @@ -0,0 +1,43 @@ +/* + * Copyright (C) 2015 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. + */ + +#undef _FORTIFY_SOURCE +#include +#include "private/libc_logging.h" + +extern "C" ssize_t __pread64_chk(int fd, void* buf, size_t count, off64_t offset, size_t buf_size) { + if (__predict_false(count > buf_size)) { + __fortify_chk_fail("pread64: prevented write past end of buffer", 0); + } + + if (__predict_false(count > SSIZE_MAX)) { + __fortify_chk_fail("pread64: count > SSIZE_MAX", 0); + } + + return pread64(fd, buf, count, offset); +} diff --git a/libc/bionic/__pread_chk.cpp b/libc/bionic/__pread_chk.cpp new file mode 100644 index 0000000..7109ce6 --- /dev/null +++ b/libc/bionic/__pread_chk.cpp @@ -0,0 +1,43 @@ +/* + * Copyright (C) 2015 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. + */ + +#undef _FORTIFY_SOURCE +#include +#include "private/libc_logging.h" + +extern "C" ssize_t __pread_chk(int fd, void* buf, size_t count, off_t offset, size_t buf_size) { + if (__predict_false(count > buf_size)) { + __fortify_chk_fail("pread: prevented write past end of buffer", 0); + } + + if (__predict_false(count > SSIZE_MAX)) { + __fortify_chk_fail("pread: count > SSIZE_MAX", 0); + } + + return pread(fd, buf, count, offset); +} diff --git a/libc/include/unistd.h b/libc/include/unistd.h index 92d3abe..a601cb7 100644 --- a/libc/include/unistd.h +++ b/libc/include/unistd.h @@ -224,6 +224,16 @@ extern int tcsetpgrp(int fd, pid_t _pid); } while (_rc == -1 && errno == EINTR); \ _rc; }) +extern ssize_t __pread_chk(int, void*, size_t, off_t, size_t); +__errordecl(__pread_dest_size_error, "pread called with size bigger than destination"); +__errordecl(__pread_count_toobig_error, "pread called with count > SSIZE_MAX"); +extern ssize_t __pread_real(int, void*, size_t, off_t) __RENAME(pread); + +extern ssize_t __pread64_chk(int, void*, size_t, off64_t, size_t); +__errordecl(__pread64_dest_size_error, "pread64 called with size bigger than destination"); +__errordecl(__pread64_count_toobig_error, "pread64 called with count > SSIZE_MAX"); +extern ssize_t __pread64_real(int, void*, size_t, off64_t) __RENAME(pread64); + extern ssize_t __read_chk(int, void*, size_t, size_t); __errordecl(__read_dest_size_error, "read called with size bigger than destination"); __errordecl(__read_count_toobig_error, "read called with count > SSIZE_MAX"); @@ -231,6 +241,62 @@ extern ssize_t __read_real(int, void*, size_t) __RENAME(read); #if defined(__BIONIC_FORTIFY) +#if defined(__USE_FILE_OFFSET64) +#define __PREAD_PREFIX(x) __pread64_ ## x +#else +#define __PREAD_PREFIX(x) __pread_ ## x +#endif + +__BIONIC_FORTIFY_INLINE +ssize_t pread(int fd, void* buf, size_t count, off_t offset) { + size_t bos = __bos0(buf); + +#if !defined(__clang__) + if (__builtin_constant_p(count) && (count > SSIZE_MAX)) { + __PREAD_PREFIX(count_toobig_error)(); + } + + if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) { + return __PREAD_PREFIX(real)(fd, buf, count, offset); + } + + if (__builtin_constant_p(count) && (count > bos)) { + __PREAD_PREFIX(dest_size_error)(); + } + + if (__builtin_constant_p(count) && (count <= bos)) { + return __PREAD_PREFIX(real)(fd, buf, count, offset); + } +#endif + + return __PREAD_PREFIX(chk)(fd, buf, count, offset, bos); +} + +__BIONIC_FORTIFY_INLINE +ssize_t pread64(int fd, void* buf, size_t count, off64_t offset) { + size_t bos = __bos0(buf); + +#if !defined(__clang__) + if (__builtin_constant_p(count) && (count > SSIZE_MAX)) { + __pread64_count_toobig_error(); + } + + if (bos == __BIONIC_FORTIFY_UNKNOWN_SIZE) { + return __pread64_real(fd, buf, count, offset); + } + + if (__builtin_constant_p(count) && (count > bos)) { + __pread64_dest_size_error(); + } + + if (__builtin_constant_p(count) && (count <= bos)) { + return __pread64_real(fd, buf, count, offset); + } +#endif + + return __pread64_chk(fd, buf, count, offset, bos); +} + __BIONIC_FORTIFY_INLINE ssize_t read(int fd, void* buf, size_t count) { size_t bos = __bos0(buf); @@ -255,6 +321,7 @@ ssize_t read(int fd, void* buf, size_t count) { return __read_chk(fd, buf, count, bos); } + #endif /* defined(__BIONIC_FORTIFY) */ __END_DECLS -- cgit v1.1