platform_bionic/libc/arch-arm/krait/bionic/memcpy.S

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/*
* Copyright (C) 2013 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.
*/
/* Assumes neon instructions and a cache line size of 32 bytes. */
#include <private/bionic_asm.h>
#include <private/libc_events.h>
/*
* This code assumes it is running on a processor that supports all arm v7
* instructions, that supports neon instructions, and that has a 32 byte
* cache line.
*/
.text
Create optimized __strcpy_chk/__strcat_chk. This change pulls the memcpy code out into a new file so that the __strcpy_chk and __strcat_chk can use it with an include. The new versions of the two chk functions uses assembly versions of strlen and memcpy to implement this check. This allows near parity with the assembly versions of strcpy/strcat. It also means that as memcpy implementations get faster, so do the chk functions. Other included changes: - Change all of the assembly labels to local labels. The other labels confuse gdb and mess up backtracing. - Add .cfi_startproc and .cfi_endproc directives so that gdb is not confused when falling through from one function to another. - Change all functions to use cfi directives since they are more powerful. - Move the memcpy_chk fail code outside of the memcpy function definition so that backtraces work properly. - Preserve lr before the calls to __fortify_chk_fail so that the backtrace actually works. Testing: - Ran the bionic unit tests. Verified all error messages in logs are set correctly. - Ran libc_test, replacing strcpy with __strcpy_chk and replacing strcat with __strcat_chk. - Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the backtrace is correct for all fortify check failures. Also verify that when falling through from __memcpy_chk to memcpy that the backtrace is still correct. Also verified the same for __memset_chk and bzero. Verified the two different paths in the cortex-a9 memset routine that save variables to the stack still show the backtrace properly. Bug: 9293744 (cherry-picked from 2be91915dcecc956d14ff281db0c7d216ca98af2) Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
2013-08-07 22:09:51 +02:00
.syntax unified
.fpu neon
Create optimized __strcpy_chk/__strcat_chk. This change pulls the memcpy code out into a new file so that the __strcpy_chk and __strcat_chk can use it with an include. The new versions of the two chk functions uses assembly versions of strlen and memcpy to implement this check. This allows near parity with the assembly versions of strcpy/strcat. It also means that as memcpy implementations get faster, so do the chk functions. Other included changes: - Change all of the assembly labels to local labels. The other labels confuse gdb and mess up backtracing. - Add .cfi_startproc and .cfi_endproc directives so that gdb is not confused when falling through from one function to another. - Change all functions to use cfi directives since they are more powerful. - Move the memcpy_chk fail code outside of the memcpy function definition so that backtraces work properly. - Preserve lr before the calls to __fortify_chk_fail so that the backtrace actually works. Testing: - Ran the bionic unit tests. Verified all error messages in logs are set correctly. - Ran libc_test, replacing strcpy with __strcpy_chk and replacing strcat with __strcat_chk. - Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the backtrace is correct for all fortify check failures. Also verify that when falling through from __memcpy_chk to memcpy that the backtrace is still correct. Also verified the same for __memset_chk and bzero. Verified the two different paths in the cortex-a9 memset routine that save variables to the stack still show the backtrace properly. Bug: 9293744 (cherry-picked from 2be91915dcecc956d14ff281db0c7d216ca98af2) Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
2013-08-07 22:09:51 +02:00
.thumb
.thumb_func
ENTRY(__memcpy_chk)
cmp r2, r3
bhi .L_memcpy_chk_fail
// Fall through to memcpy...
END(__memcpy_chk)
ENTRY(memcpy)
Create optimized __strcpy_chk/__strcat_chk. This change pulls the memcpy code out into a new file so that the __strcpy_chk and __strcat_chk can use it with an include. The new versions of the two chk functions uses assembly versions of strlen and memcpy to implement this check. This allows near parity with the assembly versions of strcpy/strcat. It also means that as memcpy implementations get faster, so do the chk functions. Other included changes: - Change all of the assembly labels to local labels. The other labels confuse gdb and mess up backtracing. - Add .cfi_startproc and .cfi_endproc directives so that gdb is not confused when falling through from one function to another. - Change all functions to use cfi directives since they are more powerful. - Move the memcpy_chk fail code outside of the memcpy function definition so that backtraces work properly. - Preserve lr before the calls to __fortify_chk_fail so that the backtrace actually works. Testing: - Ran the bionic unit tests. Verified all error messages in logs are set correctly. - Ran libc_test, replacing strcpy with __strcpy_chk and replacing strcat with __strcat_chk. - Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the backtrace is correct for all fortify check failures. Also verify that when falling through from __memcpy_chk to memcpy that the backtrace is still correct. Also verified the same for __memset_chk and bzero. Verified the two different paths in the cortex-a9 memset routine that save variables to the stack still show the backtrace properly. Bug: 9293744 (cherry-picked from 2be91915dcecc956d14ff281db0c7d216ca98af2) Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
2013-08-07 22:09:51 +02:00
pld [r1, #64]
stmfd sp!, {r0, lr}
.cfi_adjust_cfa_offset 8
Create optimized __strcpy_chk/__strcat_chk. This change pulls the memcpy code out into a new file so that the __strcpy_chk and __strcat_chk can use it with an include. The new versions of the two chk functions uses assembly versions of strlen and memcpy to implement this check. This allows near parity with the assembly versions of strcpy/strcat. It also means that as memcpy implementations get faster, so do the chk functions. Other included changes: - Change all of the assembly labels to local labels. The other labels confuse gdb and mess up backtracing. - Add .cfi_startproc and .cfi_endproc directives so that gdb is not confused when falling through from one function to another. - Change all functions to use cfi directives since they are more powerful. - Move the memcpy_chk fail code outside of the memcpy function definition so that backtraces work properly. - Preserve lr before the calls to __fortify_chk_fail so that the backtrace actually works. Testing: - Ran the bionic unit tests. Verified all error messages in logs are set correctly. - Ran libc_test, replacing strcpy with __strcpy_chk and replacing strcat with __strcat_chk. - Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the backtrace is correct for all fortify check failures. Also verify that when falling through from __memcpy_chk to memcpy that the backtrace is still correct. Also verified the same for __memset_chk and bzero. Verified the two different paths in the cortex-a9 memset routine that save variables to the stack still show the backtrace properly. Bug: 9293744 (cherry-picked from 2be91915dcecc956d14ff281db0c7d216ca98af2) Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
2013-08-07 22:09:51 +02:00
.cfi_rel_offset r0, 0
.cfi_rel_offset lr, 4
#include "memcpy_base.S"
// Undo the cfi directives from above.
.cfi_adjust_cfa_offset -8
.cfi_restore r0
.cfi_restore lr
.L_memcpy_chk_fail:
Create optimized __strcpy_chk/__strcat_chk. This change pulls the memcpy code out into a new file so that the __strcpy_chk and __strcat_chk can use it with an include. The new versions of the two chk functions uses assembly versions of strlen and memcpy to implement this check. This allows near parity with the assembly versions of strcpy/strcat. It also means that as memcpy implementations get faster, so do the chk functions. Other included changes: - Change all of the assembly labels to local labels. The other labels confuse gdb and mess up backtracing. - Add .cfi_startproc and .cfi_endproc directives so that gdb is not confused when falling through from one function to another. - Change all functions to use cfi directives since they are more powerful. - Move the memcpy_chk fail code outside of the memcpy function definition so that backtraces work properly. - Preserve lr before the calls to __fortify_chk_fail so that the backtrace actually works. Testing: - Ran the bionic unit tests. Verified all error messages in logs are set correctly. - Ran libc_test, replacing strcpy with __strcpy_chk and replacing strcat with __strcat_chk. - Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the backtrace is correct for all fortify check failures. Also verify that when falling through from __memcpy_chk to memcpy that the backtrace is still correct. Also verified the same for __memset_chk and bzero. Verified the two different paths in the cortex-a9 memset routine that save variables to the stack still show the backtrace properly. Bug: 9293744 (cherry-picked from 2be91915dcecc956d14ff281db0c7d216ca98af2) Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
2013-08-07 22:09:51 +02:00
// Preserve lr for backtrace.
push {lr}
.cfi_adjust_cfa_offset 4
Create optimized __strcpy_chk/__strcat_chk. This change pulls the memcpy code out into a new file so that the __strcpy_chk and __strcat_chk can use it with an include. The new versions of the two chk functions uses assembly versions of strlen and memcpy to implement this check. This allows near parity with the assembly versions of strcpy/strcat. It also means that as memcpy implementations get faster, so do the chk functions. Other included changes: - Change all of the assembly labels to local labels. The other labels confuse gdb and mess up backtracing. - Add .cfi_startproc and .cfi_endproc directives so that gdb is not confused when falling through from one function to another. - Change all functions to use cfi directives since they are more powerful. - Move the memcpy_chk fail code outside of the memcpy function definition so that backtraces work properly. - Preserve lr before the calls to __fortify_chk_fail so that the backtrace actually works. Testing: - Ran the bionic unit tests. Verified all error messages in logs are set correctly. - Ran libc_test, replacing strcpy with __strcpy_chk and replacing strcat with __strcat_chk. - Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the backtrace is correct for all fortify check failures. Also verify that when falling through from __memcpy_chk to memcpy that the backtrace is still correct. Also verified the same for __memset_chk and bzero. Verified the two different paths in the cortex-a9 memset routine that save variables to the stack still show the backtrace properly. Bug: 9293744 (cherry-picked from 2be91915dcecc956d14ff281db0c7d216ca98af2) Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
2013-08-07 22:09:51 +02:00
.cfi_rel_offset lr, 0
ldr r0, error_message
ldr r1, error_code
1:
add r0, pc
bl __fortify_chk_fail
error_code:
.word BIONIC_EVENT_MEMCPY_BUFFER_OVERFLOW
error_message:
Create optimized __strcpy_chk/__strcat_chk. This change pulls the memcpy code out into a new file so that the __strcpy_chk and __strcat_chk can use it with an include. The new versions of the two chk functions uses assembly versions of strlen and memcpy to implement this check. This allows near parity with the assembly versions of strcpy/strcat. It also means that as memcpy implementations get faster, so do the chk functions. Other included changes: - Change all of the assembly labels to local labels. The other labels confuse gdb and mess up backtracing. - Add .cfi_startproc and .cfi_endproc directives so that gdb is not confused when falling through from one function to another. - Change all functions to use cfi directives since they are more powerful. - Move the memcpy_chk fail code outside of the memcpy function definition so that backtraces work properly. - Preserve lr before the calls to __fortify_chk_fail so that the backtrace actually works. Testing: - Ran the bionic unit tests. Verified all error messages in logs are set correctly. - Ran libc_test, replacing strcpy with __strcpy_chk and replacing strcat with __strcat_chk. - Ran the debugger on nexus10, nexus4, and old nexus7. Verified that the backtrace is correct for all fortify check failures. Also verify that when falling through from __memcpy_chk to memcpy that the backtrace is still correct. Also verified the same for __memset_chk and bzero. Verified the two different paths in the cortex-a9 memset routine that save variables to the stack still show the backtrace properly. Bug: 9293744 (cherry-picked from 2be91915dcecc956d14ff281db0c7d216ca98af2) Change-Id: Ia407b74d3287d0b6af0139a90b6eb3bfaebf2155
2013-08-07 22:09:51 +02:00
.word error_string-(1b+4)
END(memcpy)
.data
error_string:
.string "memcpy: prevented write past end of buffer"