Add _FORTIFY_SOURCE support for snprintf, vsnprintf
At this time, we opt out of these protections for clang, as clang
does not implement __builtin_va_arg_pack().
http://clang.llvm.org/docs/UsersManual.html#c_unimpl_gcc
Change-Id: I73ebe5ec8dad1dca8898a76d6afb693a25f75375
Fix runtime error when snprintf() FORTIFY_SOURCE protections are
applied. The size passed to snprintf() is larger than the tmp
buffer size, which results in a runtime assertion failure.
Even though the size passed to snprintf is larger than the buffer,
there's no danger of overwriting the buffer because of the format
string passed to snprintf.
Change-Id: I35f0217d25f3b9c6d04c5a76c3238759c235545a
This was misleading 'configure' into thinking we actually support AF_LINK,
but we're Linux, so we don't, and we never implemented the functions we
declared here either.
Reported to AOSP by Jun-ya Kato.
(cherry-pick of 5056f1fad1187cd67729bb04ba72397d78256f03.)
Change-Id: Ic67f674d2221497c8166994812bb5fc7f0831066
This was misleading 'configure' into thinking we actually support AF_LINK,
but we're Linux, so we don't, and we never implemented the functions we
declared here either.
Reported to AOSP by Jun-ya Kato.
Change-Id: I111f9887f3812469b411b9cf5124d9dd624f19f7
Ensure that strcat / strncat check for integer overflows
when computing the length of the resulting string.
Change-Id: Ib806ad33a0d3b50876f384bc17787a28f0dddc37
I've basically just copied the relevant bits out of liblog and
EventLog.cpp. While this will let us do the uid logging we want
to address the concerns in 245c07027f78565858dd489eb0d94c3d48743e9d
it doesn't give us much else.
Change-Id: Icac6ff20bc0a3ade5927f6f76fedffe1ae6f8522
Add _FORTIFY_SOURCE support for the following functions:
* memset
* bzero
Move the __BIONIC_FORTIFY_INLINE definition to cdefs.h so it
can be used from multiple header files.
Change-Id: Iead4d5e35de6ec97786d58ee12573f9b11135bb7
Add initial support for -D_FORTIFY_SOURCE to bionic for the
following functions:
* memcpy
* memmove
* strcpy
* strcat
* strncpy
* strncat
This change adds a new version of the above functions which passes
the size of the destination buffer to __builtin___*_chk.
If the compiler can determine, at compile time, that the destination
buffer is large enough, or the destination buffer can point to an object
of unknown size, then the check call is bypassed.
If the compiler can't make a compile time decision, then it calls
the __*_chk() function, which does a runtime buffer size check
These options are only enabled if the code is compiled with
-D_FORTIFY_SOURCE=1 or 2, and only when optimizations are enabled.
Please see
* http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
* http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html
for additional details on FORTIFY_SOURCE.
Testing: Compiled the entire Android tree with -D_FORTIFY_SOURCE=1,
and verified that everything appears to be working properly.
Also created a test buffer overflow, and verified that it was
caught by this change.
Change-Id: I4fddb445bafe92b16845b22458d72e6dedd24fbc
Before changing mmap() permission to PROT_NONE in alloc_mem_region(),
such libraries once worked with a bug that uses mmap'ed region outside of
memory region allocated by alloc_mem_region(). This possibly incurs
SIGSEGV because it can overwrite memory region of previously loaded
library, but it sometimes worked, depending on loading order.
After PROT_NONE, this caused SIGSEGV earlier during calculation of
si->phdr in load_library(), but this was fixed by:
75917c84d1 Use mmap to read an ...
Now the behaviour is the same as before applying PROT_NONE in
alloc_mem_region().
This CL fixed the original issue, supporting shared libraries that have
non-zero p_vaddr in first (= with lowest p_vaddr) PT_LOAD segment.
Bug: 6561258
Change-Id: Ib6176dd3e44c4d99a340eb1cbd16fb037586b0bc
This patch is a rewrite of libc.debug.malloc = 10 (chk_malloc). It provides
the same features as the original (poison freed memory, detect heap overruns
and underruns), except that it provides more debugging information whenever it
detects a problem.
In addition to the original features, the new chk_malloc() implementation
detects multiple frees within a given range of the last N allocations, N being
configurable via the system property libc.debug.malloc.backlog.
Finally, this patch keeps track of all outstanding memory allocations. On
program exit, we walk that list and report each outstanding allocation.
(There is support (not enabled) for a scanner thread periodically walks over
the list of outstanding allocations as well as the backlog of recently-freed
allocations, checking for heap-usage errors.)
Feature overview:
1) memory leaks
2) multiple frees
3) use after free
4) overrun
Implementation:
-- for each allocation, there is a:
1) stack trace at the time the allocation is made
2) if the memory is freed, there is also a stack trace at the point
3) a front and rear guard (fence)
4) the stack traces are kept together with the allocation
-- the following lists and maintained
1) all outstanding memory allocations
3) a backlog of allocations what are freed; when you call free(), instead of
actually freed, the allocation is moved to this backlog;
4) when the backlog of allocations gets full, the oldest entry gets evicted
from it; at that point, the allocation is checked for overruns or
use-after-free errors, and then actually freed.
5) when the program exits, the list of outstanding allocations and the
backlog are inspected for errors, then freed;
To use this, set the following system properties before running the process or
processes you want to inspect:
libc.malloc.debug.backlog # defaults to 100
libc.malloc.debug 10
When a problem is detected, you will see the following on logcat for a multiple
free:
E/libc ( 7233): +++ ALLOCATION 0x404b9278 SIZE 10 BYTES MULTIPLY FREED!
E/libc ( 7233): +++ ALLOCATION 0x404b9278 SIZE 10 ALLOCATED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c658 /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d80 /system/lib/libc.so
E/libc ( 7233): #03 pc 4009647c /system/bin/malloctest
E/libc ( 7233): #04 pc 00016f24 /system/lib/libc.so
E/libc ( 7233): +++ ALLOCATION 0x404b9278 SIZE 10 FIRST FREED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c7d2 /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d94 /system/lib/libc.so
E/libc ( 7233): #03 pc 40096490 /system/bin/malloctest
E/libc ( 7233): #04 pc 00016f24 /system/lib/libc.so
E/libc ( 7233): +++ ALLOCATION 0x404b9278 SIZE 10 NOW BEING FREED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c6ac /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d94 /system/lib/libc.so
E/libc ( 7233): #03 pc 400964a0 /system/bin/malloctest
E/libc ( 7233): #04 pc 00016f24 /system/lib/libc.so
The following for a heap overrun and underrun:
E/libc ( 7233): +++ REAR GUARD MISMATCH [10, 11)
E/libc ( 7233): +++ ALLOCATION 0x404b9198 SIZE 10 HAS A CORRUPTED REAR GUARD
E/libc ( 7233): +++ ALLOCATION 0x404b9198 SIZE 10 ALLOCATED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c658 /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d80 /system/lib/libc.so
E/libc ( 7233): #03 pc 40096438 /system/bin/malloctest
E/libc ( 7233): #04 pc 00016f24 /system/lib/libc.so
E/libc ( 7233): +++ ALLOCATION 0x404b9198 SIZE 10 FREED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c7d2 /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d94 /system/lib/libc.so
E/libc ( 7233): #03 pc 40096462 /system/bin/malloctest
E/libc ( 7233): #04 pc 00016f24 /system/lib/libc.so
E/libc ( 7233): +++ ALLOCATION 0x404b9358 SIZE 10 HAS A CORRUPTED FRONT GUARD
E/libc ( 7233): +++ ALLOCATION 0x404b9358 SIZE 10 ALLOCATED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c658 /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d80 /system/lib/libc.so
E/libc ( 7233): #03 pc 400964ba /system/bin/malloctest
E/libc ( 7233): #04 pc 00016f24 /system/lib/libc.so
E/libc ( 7233): +++ ALLOCATION 0x404b9358 SIZE 10 FREED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c7d2 /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d94 /system/lib/libc.so
E/libc ( 7233): #03 pc 400964e4 /system/bin/malloctest
E/libc ( 7233): #04 pc 00016f24 /system/lib/libc.so
The following for a memory leak:
E/libc ( 7233): +++ THERE ARE 1 LEAKED ALLOCATIONS
E/libc ( 7233): +++ DELETING 4096 BYTES OF LEAKED MEMORY AT 0x404b95e8 (1 REMAINING)
E/libc ( 7233): +++ ALLOCATION 0x404b95e8 SIZE 4096 ALLOCATED HERE:
E/libc ( 7233): *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
E/libc ( 7233): #00 pc 0000c35a /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #01 pc 0000c658 /system/lib/libc_malloc_debug_leak.so
E/libc ( 7233): #02 pc 00016d80 /system/lib/libc.so
E/libc ( 7233): #03 pc 0001bc94 /system/lib/libc.so
E/libc ( 7233): #04 pc 0001edf6 /system/lib/libc.so
E/libc ( 7233): #05 pc 0001b80a /system/lib/libc.so
E/libc ( 7233): #06 pc 0001c086 /system/lib/libc.so
E/libc ( 7233): #07 pc 40096402 /system/bin/malloctest
E/libc ( 7233): #08 pc 00016f24 /system/lib/libc.so
Change-Id: Ic440e9d05a01e2ea86b25e8998714e88bc2d16e0
Signed-off-by: Iliyan Malchev <malchev@google.com>
Rewrite
crtbegin.S -> crtbegin.c
crtbegin_so.S -> crtbegin_so.c
This change allows us to generate PIC code without relying
on text relocations.
As a consequence of this rewrite, also rewrite
__dso_handle.S -> __dso_handle.c
__dso_handle_so.S -> __dso_handle_so.c
atexit.S -> atexit.c
In crtbegin.c _start, place the __PREINIT_ARRAY__, __INIT_ARRAY__,
__FINI_ARRAY__, and __CTOR_LIST__ variables onto the stack, instead of
passing a pointer to the text section of the binary.
This change appears sorta wonky, as I attempted to preserve,
as much as possible, the structure of the original assembly.
As a result, you have C files including other C files, and other
programming uglyness.
Result: This change reduces the number of files with text-relocations
from 315 to 19 on my Android build.
Before:
$ scanelf -aR $OUT/system | grep TEXTREL | wc -l
315
After:
$ scanelf -aR $OUT/system | grep TEXTREL | wc -l
19
Change-Id: Ib9f98107c0eeabcb606e1ddc7ed7fc4eba01c9c4
