C (but not C++) has a concept of a flexible array member, which
is documented at https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html .
Using a flexible array member indicates that the structure is
really a header for a variable length object.
In logd's case, the variable length structure android_event_string_t
was embedded within another structure called
android_log_event_string_t. This makes gcc's __builtin_object_size()
function really confused. When compiling with C++,
__builtin_object_size(android_log_event_string_t.payload.data, 1)
would return 0, whereas if you compiled the code with C, the same
call would (properly) return -1.
Code which does automatic bounds checking, such as the proposed
patch at https://android-review.googlesource.com/145411 , will
cause problems for logd if this syntax is used.
Don't try to embed a variable length structure within another
structure. This doesn't appear to be valid C nor C++, and
while it's worked, it seems problematic.
Instead, inline the structure so it's one big happy structure.
Change-Id: I8ac02b7142a4f6560f5f80df2effcf720f9896fc
- logDmesg method consumes considerable memory
resources (typically 128KB depending on kernel)
- In the future (eg: klogd, syslogd) there may be need to
feed multiple logs or threads with the retrieved data.
- By moving the actions of logDmesg into the mainline that
instantiates the thread objects, we can leverage a single
allocation of the the kernel log allocation.
- logDmesg (private) is replaced with log (public) which
has a more useful and descriptive purpose for the class.
Change-Id: Ie2dd0370661493c1e596a7e486904a0e8caab9ff
Impose a limit of 20 selinux denials per second. Denials beyond
that point don't add any value, and have the potential to cause
crashes or denial of service attacks.
Do some other misc cleanup while I'm here.
Bug: 18341932
Change-Id: I6125d629ae4d6ae131d2e53bfa41e1f50277d402
- auditd spawn log copy to events and main
- logcat delete events as one of the default logs
- debuggerd do not collect events.
- squish multiple spaces
- switch from strcpy to memmove for overlapping buffers
BUG: 14626551
Change-Id: I89b30273ce931ed2b25a53ea9be48e77f4c1bbf4
- auditd switch to recording logs to events log id
- logcat add events as one of the default logs
- debuggerd collect events log as well.
ToDo: debuggerd & bugreport collect intermixed logs.
BUG: 14626551
Change-Id: I958f0e729b7596748be57488a38824db5645be7b
- permits easier determination of logd thread at
fault in a stack trace from debuggerd.
Bug: 14275676
Change-Id: Iac2c523147e2bcce34ab7ddcecd02582c5fa7cc0
Initial commit for an audit daemon that writes kernel audit
messages to the Android logger. The daemon searches dmesg
for all lines that contain "audit" and writes them. Then
receiving the messages from the netlink socket.
It also formats the messages so they are compatable with
ausearch (type=<t> <m> format)
Modified: Mark Salyzyn <salyzyn@google.com>
- do not start auditd
- merge into logd, stripping unnecessary file logging.
- Convert headers and code to support C++
- Fix bugs in libaudit
- squash timestamp (replace with 0.0) due to duplication
- squash pid due to duplication
- squash comm due to duplication
Change-Id: I421bcf33e7e670d596628b1b5c7c25536ce2d3fe
