diff options
Diffstat (limited to 'executor/common_linux.h')
| -rw-r--r-- | executor/common_linux.h | 218 |
1 files changed, 137 insertions, 81 deletions
diff --git a/executor/common_linux.h b/executor/common_linux.h index 26137e5b7..0e185553c 100644 --- a/executor/common_linux.h +++ b/executor/common_linux.h @@ -70,7 +70,7 @@ static int event_timedwait(event_t* ev, uint64 timeout) } #endif -#if SYZ_EXECUTOR || SYZ_FAULT_INJECTION || SYZ_ENABLE_CGROUPS || SYZ_SANDBOX_NONE || \ +#if SYZ_EXECUTOR || SYZ_REPEAT || SYZ_TUN_ENABLE || SYZ_FAULT_INJECTION || SYZ_SANDBOX_NONE || \ SYZ_SANDBOX_SETUID || SYZ_SANDBOX_NAMESPACE || SYZ_SANDBOX_ANDROID_UNTRUSTED_APP #include <errno.h> #include <fcntl.h> @@ -1677,6 +1677,8 @@ static void reset_ebtables() static void checkpoint_net_namespace(void) { #if SYZ_EXECUTOR + if (!flag_enable_net_reset) + return; if (flag_sandbox == sandbox_setuid) return; #endif @@ -1689,6 +1691,8 @@ static void checkpoint_net_namespace(void) static void reset_net_namespace(void) { #if SYZ_EXECUTOR + if (!flag_enable_net_reset) + return; if (flag_sandbox == sandbox_setuid) return; #endif @@ -1699,7 +1703,7 @@ static void reset_net_namespace(void) } #endif -#if SYZ_EXECUTOR || SYZ_ENABLE_CGROUPS +#if SYZ_EXECUTOR || (SYZ_ENABLE_CGROUPS && (SYZ_SANDBOX_NONE || SYZ_SANDBOX_SETUID || SYZ_SANDBOX_NAMESPACE || SYZ_SANDBOX_ANDROID_UNTRUSTED_APP)) #include <fcntl.h> #include <sys/mount.h> #include <sys/stat.h> @@ -1707,6 +1711,10 @@ static void reset_net_namespace(void) static void setup_cgroups() { +#if SYZ_EXECUTOR + if (!flag_enable_cgroups) + return; +#endif if (mkdir("/syzcgroup", 0777)) { debug("mkdir(/syzcgroup) failed: %d\n", errno); } @@ -1741,10 +1749,122 @@ static void setup_cgroups() } } -// TODO(dvyukov): this should be under a separate define for separate minimization, -// but for now we bundle this with cgroups. +#if SYZ_EXECUTOR || SYZ_REPEAT +static void setup_cgroups_loop() +{ +#if SYZ_EXECUTOR + if (!flag_enable_cgroups) + return; +#endif + int pid = getpid(); + char file[128]; + char cgroupdir[64]; + snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); + if (mkdir(cgroupdir, 0777)) { + debug("mkdir(%s) failed: %d\n", cgroupdir, errno); + } + // Restrict number of pids per test process to prevent fork bombs. + // We have up to 16 threads + main process + loop. + // 32 pids should be enough for everyone. + snprintf(file, sizeof(file), "%s/pids.max", cgroupdir); + write_file(file, "32"); + // Restrict memory consumption. + // We have some syscalls that inherently consume lots of memory, + // e.g. mounting some filesystem images requires at least 128MB + // image in memory. We restrict RLIMIT_AS to 200MB. Here we gradually + // increase low/high/max limits to make things more interesting. + // Also this takes into account KASAN quarantine size. + // If the limit is lower than KASAN quarantine size, then it can happen + // so that we kill the process, but all of its memory is in quarantine + // and is still accounted against memcg. As the result memcg won't + // allow to allocate any memory in the parent and in the new test process. + // The current limit of 300MB supports up to 9.6GB RAM (quarantine is 1/32). + snprintf(file, sizeof(file), "%s/memory.low", cgroupdir); + write_file(file, "%d", 298 << 20); + snprintf(file, sizeof(file), "%s/memory.high", cgroupdir); + write_file(file, "%d", 299 << 20); + snprintf(file, sizeof(file), "%s/memory.max", cgroupdir); + write_file(file, "%d", 300 << 20); + // Setup some v1 groups to make things more interesting. + snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); + write_file(file, "%d", pid); + snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); + if (mkdir(cgroupdir, 0777)) { + debug("mkdir(%s) failed: %d\n", cgroupdir, errno); + } + snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); + write_file(file, "%d", pid); + snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); + if (mkdir(cgroupdir, 0777)) { + debug("mkdir(%s) failed: %d\n", cgroupdir, errno); + } + snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); + write_file(file, "%d", pid); +} + +static void setup_cgroups_test() +{ +#if SYZ_EXECUTOR + if (!flag_enable_cgroups) + return; +#endif + char cgroupdir[64]; + snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); + if (symlink(cgroupdir, "./cgroup")) { + debug("symlink(%s, ./cgroup) failed: %d\n", cgroupdir, errno); + } + snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); + if (symlink(cgroupdir, "./cgroup.cpu")) { + debug("symlink(%s, ./cgroup.cpu) failed: %d\n", cgroupdir, errno); + } + snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); + if (symlink(cgroupdir, "./cgroup.net")) { + debug("symlink(%s, ./cgroup.net) failed: %d\n", cgroupdir, errno); + } +} +#endif + +#if SYZ_EXECUTOR || SYZ_SANDBOX_NAMESPACE +void initialize_cgroups() +{ +#if SYZ_EXECUTOR + if (!flag_enable_cgroups) + return; +#endif + if (mkdir("./syz-tmp/newroot/syzcgroup", 0700)) + fail("mkdir failed"); + if (mkdir("./syz-tmp/newroot/syzcgroup/unified", 0700)) + fail("mkdir failed"); + if (mkdir("./syz-tmp/newroot/syzcgroup/cpu", 0700)) + fail("mkdir failed"); + if (mkdir("./syz-tmp/newroot/syzcgroup/net", 0700)) + fail("mkdir failed"); + unsigned bind_mount_flags = MS_BIND | MS_REC | MS_PRIVATE; + if (mount("/syzcgroup/unified", "./syz-tmp/newroot/syzcgroup/unified", NULL, bind_mount_flags, NULL)) { + debug("mount(cgroup2, MS_BIND) failed: %d\n", errno); + } + if (mount("/syzcgroup/cpu", "./syz-tmp/newroot/syzcgroup/cpu", NULL, bind_mount_flags, NULL)) { + debug("mount(cgroup/cpu, MS_BIND) failed: %d\n", errno); + } + if (mount("/syzcgroup/net", "./syz-tmp/newroot/syzcgroup/net", NULL, bind_mount_flags, NULL)) { + debug("mount(cgroup/net, MS_BIND) failed: %d\n", errno); + } +} +#endif +#endif + +#if SYZ_EXECUTOR || (SYZ_ENABLE_BINFMT_MISC && (SYZ_SANDBOX_NONE || SYZ_SANDBOX_SETUID || SYZ_SANDBOX_NAMESPACE || SYZ_SANDBOX_ANDROID_UNTRUSTED_APP)) +#include <fcntl.h> +#include <sys/mount.h> +#include <sys/stat.h> +#include <sys/types.h> + static void setup_binfmt_misc() { +#if SYZ_EXECUTOR + if (!flag_enable_binfmt_misc) + return; +#endif if (mount(0, "/proc/sys/fs/binfmt_misc", "binfmt_misc", 0, 0)) { debug("mount(binfmt_misc) failed: %d\n", errno); } @@ -1764,6 +1884,8 @@ static void setup_common() } #if SYZ_EXECUTOR || SYZ_ENABLE_CGROUPS setup_cgroups(); +#endif +#if SYZ_EXECUTOR || SYZ_ENABLE_BINFMT_MISC setup_binfmt_misc(); #endif } @@ -2017,23 +2139,7 @@ static int namespace_sandbox_proc(void* arg) if (mount("/sys", "./syz-tmp/newroot/sys", 0, bind_mount_flags, NULL)) fail("mount(sysfs) failed"); #if SYZ_EXECUTOR || SYZ_ENABLE_CGROUPS - if (mkdir("./syz-tmp/newroot/syzcgroup", 0700)) - fail("mkdir failed"); - if (mkdir("./syz-tmp/newroot/syzcgroup/unified", 0700)) - fail("mkdir failed"); - if (mkdir("./syz-tmp/newroot/syzcgroup/cpu", 0700)) - fail("mkdir failed"); - if (mkdir("./syz-tmp/newroot/syzcgroup/net", 0700)) - fail("mkdir failed"); - if (mount("/syzcgroup/unified", "./syz-tmp/newroot/syzcgroup/unified", NULL, bind_mount_flags, NULL)) { - debug("mount(cgroup2, MS_BIND) failed: %d\n", errno); - } - if (mount("/syzcgroup/cpu", "./syz-tmp/newroot/syzcgroup/cpu", NULL, bind_mount_flags, NULL)) { - debug("mount(cgroup/cpu, MS_BIND) failed: %d\n", errno); - } - if (mount("/syzcgroup/net", "./syz-tmp/newroot/syzcgroup/net", NULL, bind_mount_flags, NULL)) { - debug("mount(cgroup/net, MS_BIND) failed: %d\n", errno); - } + initialize_cgroups(); #endif if (mkdir("./syz-tmp/pivot", 0777)) fail("mkdir failed"); @@ -2354,15 +2460,18 @@ retry: static int inject_fault(int nth) { +#if SYZ_EXECUTOR + if (!flag_enable_fault_injection) + return 0; +#endif int fd; - char buf[16]; - fd = open("/proc/thread-self/fail-nth", O_RDWR); // We treat errors here as temporal/non-critical because we see // occasional ENOENT/EACCES errors returned. It seems that fuzzer // somehow gets its hands to it. if (fd == -1) exitf("failed to open /proc/thread-self/fail-nth"); + char buf[16]; sprintf(buf, "%d", nth + 1); if (write(fd, buf, strlen(buf)) != (ssize_t)strlen(buf)) exitf("failed to write /proc/thread-self/fail-nth"); @@ -2373,6 +2482,8 @@ static int inject_fault(int nth) #if SYZ_EXECUTOR static int fault_injected(int fail_fd) { + if (!flag_enable_fault_injection) + return 0; char buf[16]; int n = read(fail_fd, buf, sizeof(buf) - 1); if (n <= 0) @@ -2455,50 +2566,7 @@ static void kill_and_wait(int pid, int* status) static void setup_loop() { #if SYZ_EXECUTOR || SYZ_ENABLE_CGROUPS - int pid = getpid(); - char cgroupdir[64]; - char file[128]; - snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); - if (mkdir(cgroupdir, 0777)) { - debug("mkdir(%s) failed: %d\n", cgroupdir, errno); - } - // Restrict number of pids per test process to prevent fork bombs. - // We have up to 16 threads + main process + loop. - // 32 pids should be enough for everyone. - snprintf(file, sizeof(file), "%s/pids.max", cgroupdir); - write_file(file, "32"); - // Restrict memory consumption. - // We have some syscalls that inherently consume lots of memory, - // e.g. mounting some filesystem images requires at least 128MB - // image in memory. We restrict RLIMIT_AS to 200MB. Here we gradually - // increase low/high/max limits to make things more interesting. - // Also this takes into account KASAN quarantine size. - // If the limit is lower than KASAN quarantine size, then it can happen - // so that we kill the process, but all of its memory is in quarantine - // and is still accounted against memcg. As the result memcg won't - // allow to allocate any memory in the parent and in the new test process. - // The current limit of 300MB supports up to 9.6GB RAM (quarantine is 1/32). - snprintf(file, sizeof(file), "%s/memory.low", cgroupdir); - write_file(file, "%d", 298 << 20); - snprintf(file, sizeof(file), "%s/memory.high", cgroupdir); - write_file(file, "%d", 299 << 20); - snprintf(file, sizeof(file), "%s/memory.max", cgroupdir); - write_file(file, "%d", 300 << 20); - // Setup some v1 groups to make things more interesting. - snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); - write_file(file, "%d", pid); - snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); - if (mkdir(cgroupdir, 0777)) { - debug("mkdir(%s) failed: %d\n", cgroupdir, errno); - } - snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); - write_file(file, "%d", pid); - snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); - if (mkdir(cgroupdir, 0777)) { - debug("mkdir(%s) failed: %d\n", cgroupdir, errno); - } - snprintf(file, sizeof(file), "%s/cgroup.procs", cgroupdir); - write_file(file, "%d", pid); + setup_cgroups_loop(); #endif #if SYZ_EXECUTOR || SYZ_RESET_NET_NAMESPACE checkpoint_net_namespace(); @@ -2534,22 +2602,10 @@ static void setup_test() prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0); setpgrp(); #if SYZ_EXECUTOR || SYZ_ENABLE_CGROUPS - char cgroupdir[64]; - snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/unified/syz%llu", procid); - if (symlink(cgroupdir, "./cgroup")) { - debug("symlink(%s, ./cgroup) failed: %d\n", cgroupdir, errno); - } - snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/cpu/syz%llu", procid); - if (symlink(cgroupdir, "./cgroup.cpu")) { - debug("symlink(%s, ./cgroup.cpu) failed: %d\n", cgroupdir, errno); - } - snprintf(cgroupdir, sizeof(cgroupdir), "/syzcgroup/net/syz%llu", procid); - if (symlink(cgroupdir, "./cgroup.net")) { - debug("symlink(%s, ./cgroup.net) failed: %d\n", cgroupdir, errno); - } + setup_cgroups_test(); +#endif // It's the leaf test process we want to be always killed first. write_file("/proc/self/oom_score_adj", "1000"); -#endif #if SYZ_EXECUTOR || SYZ_TUN_ENABLE // Read all remaining packets from tun to better // isolate consequently executing programs. |