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13 commits

Author SHA1 Message Date
Tom Cherry
4362f897f7 Only use uids and gids for which we've allocated AIDs
Currently, getpwnam, getpwent, etc return successfully for any uid
from AID_APP_START (10000) to AID_USER_OFFSET (100000) for each user.
This is not correct however, as only specific ranges above
AID_APP_START are reserved as valid ranges.  This change corrects this.

This is particularly important as the newly added AID_OVERFLOWUID is
65534, which is above AID_APP_START but not in any reserved range,
collided with the faulty returned values.

Bug: 69119022
Bug: 69128408
Test: pwd/grp bionic unit tests
Change-Id: I3dae97a90597915fa30a88fe27cda88b107e9c35
2017-11-15 10:31:49 -08:00
Goran Jakovljevic
ea827925ab Define BIONIC_STOP_UNWIND for mips
This fixes mips and mips64 build failures.

Test: successful aosp_mips-eng and aosp_mips64-eng builds
Change-Id: I6648b9cae876cda13369cf10edf61ce9fdca342c
2017-10-13 14:22:10 +02:00
Treehugger Robot
3dacc47642 Merge "Add a legacy inline for mmap64." 2017-10-06 22:20:54 +00:00
Dan Albert
a613d0df5c Add a legacy inline for mmap64.
While this was never an inline, this function alone has caused most of
the bug reports related to _FILE_OFFSET_BITS=64. Providing an inline
for it should allow a lot more code to build with _FILE_OFFSET_BITS=64
when targeting pre-L.

Test: make checkbuild
Test: built trivial cc_binary for LP32 against API 14 with
      _FILE_OFFSET_BITS=64 set
Bug: lots
Change-Id: I8479d34af4da358c11423bee43d45b59e9d4143e
2017-10-05 23:41:47 -07:00
Christopher Ferris
93ea09f65c Add directives to force stop unwinding.
On aarch64/x86/x86_64 add a macro that inserts a cfi directive that will
stop unwinding.

For arm, clang doesn't allow emitting .cantunwind, so add a comment and
leave it the same as it current is.

Add this macro to __libc_init and __start_thread.

Also, remove duplicate compilation of libc_init_static.cpp that already
includes the static library that includes that file.

Bug: 15469122

Test: Did unwinds using new unwinder tool (unwind) and debuggerd -b
Test: and verified new unwinder works on aarch64/x86/x86_64.
Test: Verified that it works on old unwinder for aarch64/x86, but
Test: x86_64 doesn't work properly, but as well as before.
Change-Id: I77302e8f6c7ba1549d98a4a164106ee82c9ecadc
2017-10-05 15:18:47 -07:00
Evgenii Stepanov
0a3637d3eb Runtime support for CFI
Control Flow Integrity support in bionic.

General design:
http://clang.llvm.org/docs/ControlFlowIntegrityDesign.html#shared-library-support

This CL implements subsections "CFI Shadow" and "CFI_SlowPath" in the above document.

Bug: 22033465
Test: bionic device tests
Change-Id: I14dfea630de468eb5620e7f55f92b1397ba06217
2017-01-18 13:13:52 -08:00
Evgenii Stepanov
d13e9a603f Align-up and randomize shared libraries.
This change implements the following property:
  Any 2**N aligned memory region on size 2**N contains no more than one DSO.

The value N can be configured, with 16 or 18 looking like a good choice.
Additionally, DSOs are loaded at random page-aligned address inside these large
regions.

This change has dual purpose:
1. Larger values of N allow a lot more compact CFI shadow implementation.
   See change I14dfea630de468eb5620e7f55f92b1397ba06217.
   For example, CFI shadow for the system_server process has the following size (RSS, KB):
   152 for N = 12, 32 for N = 16, 16 for N = 18.
2. Extra randomization is good for security.

This change does not result in extra RAM usage, because everything is still page-aligned.
It does result in a bit more VM fragmentation because of the gaps between shared libraries.
As it turns out, this fragmentation is barely noticeable because the kernel creates new mapping
at the highest possible address, and we do enough small mappings to almost completely fill the
gaps (ex. in the Zygote the gaps are filled with .ttf file mappings and thread stacks).

I've measured VM fragmentation as the sum of all VM gaps (unmapped regions) that are larger
than 1MB according to /proc/$PID/maps. On aosp_angler-userdebug, the numbers are (in GB):

                |   N = 12  |  N = 18
system_server   |   521.9   |  521.1
zygote64        |   522.1   |  521.3
zygote32        |   2.55    |  2.55
mediaserver     |   4.00    |  4.00

Change-Id: Ia6df840dd409c82837efd1f263be420d9723c84a
2016-07-19 18:18:22 -07:00
Christopher Ferris
0b13f29b2c Fix missing parentheses.
The BIONIC_ROUND_UP_POWER_OF_2 macro did not have parentheses around
the whole expression. This lead to the wrong value being computed when
used as part of a mathematical expression such as this:

  value = BIONIC_ROUND_UP_POWER_OF_2(value) - 1;

This only happens on 64 bit abis.

Change-Id: I6f8afbdaf16fe64a88fa0246d074b3534c9159c1
2015-12-16 16:11:04 -08:00
Andreas Gampe
00bbc7f69f Bionic: Make DISALLOW_COPY_AND_ASSIGN conditional
Make the definition of DISALLOW_COPY_AND_ASSIGN conditional. This is
so that the projects that include libnativehelper and bionic macros
do not have to be careful in which order those projects are included.

Bug: 18334516
Change-Id: Ib12a2c2b7ad2e360edcf3b26cb1be626540fadc1
2014-11-11 11:16:57 -08:00
Dmitriy Ivanov
d9ff722661 Refactoring: C++11 style DISABLE_ bionic marcos
Enable the -std=gnu++11 flag for libstdc++ static and
  dynamic libs.

  ScopeGuard uses DISABLE_ macros instead of '= delete';

Change-Id: I07e21b306f95fffd49345f7fa136cfdac61e0225
2014-09-08 17:51:31 -07:00
Christopher Ferris
27047faf28 Fix BIONIC_ROUND_UP_POWER_OF_2 for 64 bit.
There were two bugs here:

- For 64 bit values, this did not properly round up.
- The macro rounded to the power of 2 less than value, not to the power
  of 2 greater than value.

Change-Id: If8cb41536a9d2f5c1bc213676f1e67a7903a36b0
2014-07-15 12:33:48 -07:00
Christopher Ferris
03eebcb6e8 Move common macros into bionic_macros.h.
Bug: 15590152
Change-Id: I730636613ef3653f68c5ab1d43b53beaf8e0dc25
2014-06-18 14:23:46 -07:00
Elliott Hughes
8eac9af24e Bring in google3-style DISALLOW_* macros.
I've been meaning to do this for a very long time...

Change-Id: Ia8c16eee7c026c3c9505399948485fb778fb0152
2014-05-09 19:12:08 -07:00