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| author | jln@chromium.org <jln@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2013-09-05 23:25:17 +0000 |
|---|---|---|
| committer | jln@chromium.org <jln@chromium.org@0039d316-1c4b-4281-b951-d872f2087c98> | 2013-09-05 23:25:17 +0000 |
| commit | 3bbc01727c811b056b71c97a6259dd967d8f031f (patch) | |
| tree | 8fc7ea9c86bf6758fe7ba2e53c92c8916455ada0 /sandbox | |
| parent | d537003da9f47ea1b1cfcf28cafdda517ed13a79 (diff) | |
| download | chromium_src-3bbc01727c811b056b71c97a6259dd967d8f031f.zip chromium_src-3bbc01727c811b056b71c97a6259dd967d8f031f.tar.gz chromium_src-3bbc01727c811b056b71c97a6259dd967d8f031f.tar.bz2 | |
Linux Sandbox: LOG error if a previous SIGSYS handler exists.
SIGSYS is a reserved signal on Linux for the seccomp-bpf sandbox.
If a previous handler for SIGSYS exists, log an error.
BUG=178166
R=markus@chromium.org
Review URL: https://codereview.chromium.org/23960006
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@221539 0039d316-1c4b-4281-b951-d872f2087c98
Diffstat (limited to 'sandbox')
| -rw-r--r-- | sandbox/linux/seccomp-bpf/trap.cc | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/sandbox/linux/seccomp-bpf/trap.cc b/sandbox/linux/seccomp-bpf/trap.cc index 3c30de35..33271e2 100644 --- a/sandbox/linux/seccomp-bpf/trap.cc +++ b/sandbox/linux/seccomp-bpf/trap.cc @@ -61,6 +61,14 @@ void SetIsInSigHandler() { } } +bool IsDefaultSignalAction(const struct sigaction& sa) { + if (sa.sa_flags & SA_SIGINFO || + sa.sa_handler != SIG_DFL) { + return false; + } + return true; +} + } // namespace namespace playground2 { @@ -74,10 +82,16 @@ Trap::Trap() struct sigaction sa = { }; sa.sa_sigaction = SigSysAction; sa.sa_flags = SA_SIGINFO | SA_NODEFER; - if (sigaction(SIGSYS, &sa, NULL) < 0) { + struct sigaction old_sa; + if (sigaction(SIGSYS, &sa, &old_sa) < 0) { SANDBOX_DIE("Failed to configure SIGSYS handler"); } + if (!IsDefaultSignalAction(old_sa)) { + // TODO(jln): make this FATAL, at least in DEBUG mode. + LOG(ERROR) << "Existing signal handler when trying to install SIGSYS"; + } + // Unmask SIGSYS sigset_t mask; if (sigemptyset(&mask) || |