diff options
| author | Jay Faulkner <jay@jvf.cc> | 2015-02-20 21:59:47 +0000 |
|---|---|---|
| committer | Zbigniew Jędrzejewski-Szmek <zbyszek@in.waw.pl> | 2015-03-04 23:18:09 -0500 |
| commit | 9a71b1122c6e49dd9227f82b2f53837c7ea13019 (patch) | |
| tree | 3de7a9645978aed8ba18312f2c5490a0231165c2 /src/nspawn | |
| parent | 9e4ded3064e9a683e004ff8f6a8ce53ac20b79d7 (diff) | |
nspawn: Map all seccomp filters to capabilities
This change makes it so all seccomp filters are mapped
to the appropriate capability and are only added if that
capability was not requested when running the container.
This unbreaks the remaining use cases broken by the
addition of seccomp filters without respecting requested
capabilities.
Co-Authored-By: Clif Houck <me@clifhouck.com>
[zj: - adapt to our coding style, make struct anonymous]
Diffstat (limited to 'src/nspawn')
| -rw-r--r-- | src/nspawn/nspawn.c | 44 |
1 files changed, 17 insertions, 27 deletions
diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 8ce5fbeb62..8833704ab7 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -2567,19 +2567,19 @@ static int setup_ipvlan(pid_t pid) { static int setup_seccomp(void) { #ifdef HAVE_SECCOMP - static const int blacklist[] = { - SCMP_SYS(kexec_load), - SCMP_SYS(open_by_handle_at), - SCMP_SYS(iopl), - SCMP_SYS(ioperm), - SCMP_SYS(swapon), - SCMP_SYS(swapoff), - }; - - static const int kmod_blacklist[] = { - SCMP_SYS(init_module), - SCMP_SYS(finit_module), - SCMP_SYS(delete_module), + static const struct { + uint64_t capability; + int syscall_num; + } blacklist[] = { + { CAP_SYS_RAWIO, SCMP_SYS(iopl)}, + { CAP_SYS_RAWIO, SCMP_SYS(ioperm)}, + { CAP_SYS_BOOT, SCMP_SYS(kexec_load)}, + { CAP_SYS_ADMIN, SCMP_SYS(swapon)}, + { CAP_SYS_ADMIN, SCMP_SYS(swapoff)}, + { CAP_SYS_ADMIN, SCMP_SYS(open_by_handle_at)}, + { CAP_SYS_MODULE, SCMP_SYS(init_module)}, + { CAP_SYS_MODULE, SCMP_SYS(finit_module)}, + { CAP_SYS_MODULE, SCMP_SYS(delete_module)}, }; scmp_filter_ctx seccomp; @@ -2597,7 +2597,10 @@ static int setup_seccomp(void) { } for (i = 0; i < ELEMENTSOF(blacklist); i++) { - r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), blacklist[i], 0); + if (arg_retain & (1ULL << blacklist[i].capability)) + continue; + + r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), blacklist[i].syscall_num, 0); if (r == -EFAULT) continue; /* unknown syscall */ if (r < 0) { @@ -2606,19 +2609,6 @@ static int setup_seccomp(void) { } } - /* If the CAP_SYS_MODULE capability is not requested then - * we'll block the kmod syscalls too */ - if (!(arg_retain & (1ULL << CAP_SYS_MODULE))) { - for (i = 0; i < ELEMENTSOF(kmod_blacklist); i++) { - r = seccomp_rule_add(seccomp, SCMP_ACT_ERRNO(EPERM), kmod_blacklist[i], 0); - if (r == -EFAULT) - continue; /* unknown syscall */ - if (r < 0) { - log_error_errno(r, "Failed to block syscall: %m"); - goto finish; - } - } - } /* Audit is broken in containers, much of the userspace audit |