Preloading libmozsandbox allows the symbol interpositions used by
sandboxing to be defined there instead of statically linked into the
executable; this patch also does that.
MozReview-Commit-ID: FL1QWLSKA0S
--HG--
rename : security/sandbox/linux/interpose/SandboxHooks.cpp => security/sandbox/linux/SandboxHooks.cpp
Now that SandboxInfo is always part of libmozsandbox, instead of being
in different places depending on widget, it doesn't need to be a
separate directory anymore.
Also updates a few comments that referenced it.
--HG--
rename : security/sandbox/linux/common/LinuxSched.h => security/sandbox/linux/LinuxSched.h
rename : security/sandbox/linux/common/SandboxInfo.cpp => security/sandbox/linux/SandboxInfo.cpp
rename : security/sandbox/linux/common/SandboxInfo.h => security/sandbox/linux/SandboxInfo.h
This way they'll continue to be at the beginning of the symbol search
path after mozsandbox returns to being a shared library instead of
statically linked into plugin-container.
--HG--
rename : security/sandbox/linux/SandboxHooks.cpp => security/sandbox/linux/interpose/SandboxHooks.cpp
This removes the unnecessary setting of c-basic-offset from all
python-mode files.
This was automatically generated using
perl -pi -e 's/; *c-basic-offset: *[0-9]+//'
... on the affected files.
The bulk of these files are moz.build files but there a few others as
well.
MozReview-Commit-ID: 2pPf3DEiZqx
--HG--
extra : rebase_source : 0a7dcac80b924174a2c429b093791148ea6ac204
The patch removes 455 occurrences of FAIL_ON_WARNINGS from moz.build files, and
adds 78 instances of ALLOW_COMPILER_WARNINGS. About half of those 78 are in
code we control and which should be removable with a little effort.
--HG--
extra : rebase_source : 82e3387abfbd5f1471e953961d301d3d97ed2973
This gives us a logging macro that's safe to use in async signal context
(cf. bug 1046210, where we needed this and didn't have it).
This patch also changes one of the format strings to work with
SafeSPrintf's format string dialect; upstream would probably take a
patch to handle those letters, but this is easier.
This gives us a logging macro that's safe to use in async signal context
(cf. bug 1046210, where we needed this and didn't have it).
This patch also changes one of the format strings to work with
SafeSPrintf's format string dialect; upstream would probably take a
patch to handle those letters, but this is easier.
This is more complicated than I'd like it to be, because we don't have
a good way to combine a specific trap function's knowledge that we want
to get a crash dump with the SIGSYS handler's copy of the unprocessed
signal info (which breakpad wants). The bpf_dsl interface requires a
specific trap function type (via the TrapRegistry superclass), so even
if we implement our own registry we can't change what's passed to it.
Normally we could use thread-local storage to get around that, but it's
not async signal safe.
As a result there is an imperfect compromise: the trap function returns
a failure with ENOSYS, Chromium's SIGSYS handler writes it into the
context, our SIGSYS handler reads it back out and uses a copy of
the original signal context for the crash dump. Other error codes
(and returning ENOSYS via the seccomp-bpf policy itself) are handled
normally.
This completely rewrites SandboxFilter.cpp and removes SandboxAssembler.
System calls are now loosely grouped by what they do, now that order
doesn't matter, and most of the intersection the content and media
plugin whitelists is moved into a common superclass. Hopefully this
improves the readability and comprehensibility of the syscall policies.
Also, the macros that take the syscall name are gone, because a plain
case label usually suffices now (the CASES_FOR_thing macros are a little
unsightly, but they're relatively simple), and at one point we saw
strange macro expansion issues with system header files that #define'd
some syscall names.
The signal handling is not migrated yet, so Trap() actions can't be used
yet; the next patch will take care of that, and to keep the intermediate
state working there's a minimal shim.
Bonus fix: non-const global variables use the "g" prefix; "s" is for
static class members and static variables in a function (where the
default is to allocate a separate copy per instance/activation).
This needs more unit tests for the various pieces of what's going on
here (LinuxCapabilities, SandboxChroot, UnshareUserNamespace()) but
that's nontrivial due to needing a single-threaded process -- and
currently they can't be run on Mozilla's CI anyway due to needing user
namespaces, and local testing can just try using GMP and manually
inspecting the child process. So that will be a followup.
This means that B2G plugin-container must (dynamically) link against
libmozsandbox in order to call into it before initializing Binder.
(Desktop Linux plugin-container already contains the sandbox code.)
Specifically:
* SandboxCrash() uses internal Gecko interfaces, so stays in libxul.
* SandboxInfo moves to libxul from libmozsandbox, which no longer exists.
* Where libxul calls Set*Sandbox(), it uses weak symbols.
* Everything remains as it was on mobile.
This changes the interface so that the code which determines the flags
can live in one place, but checking the flags doesn't need to call into
another library.
Also removes the no-op wrappers for Set*Sandbox when disabled at build
time; nothing used them, one of them was unusable due to having the wrong
type, and all they really accomplish is allowing sloppiness with ifdefs
(which could hide actual mistakes).
This creates libmozsandbox.so on builds that use sandboxing
(MOZ_CONTENT_SANDBOX or MOZ_GMP_SANDBOX).
The unavoidably libxul-dependent parts, for invoking the crash reporter
and printing the JS context, are separated into glue/SandboxCrash.cpp
and invoked via a callback.
