2023-07-10 08:07:43

by syzbot

[permalink] [raw]
Subject: [syzbot] [dri?] KASAN: slab-use-after-free Read in drm_atomic_helper_wait_for_vblanks

Hello,

syzbot found the following issue on:

HEAD commit: 03275585cabd afs: Fix accidental truncation when storing d..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16db258ca80000
kernel config: https://syzkaller.appspot.com/x/.config?x=d576750da57ebbb5
dashboard link: https://syzkaller.appspot.com/bug?extid=380dcf72caf0b5ef5537
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: i386

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image (non-bootable): https://storage.googleapis.com/syzbot-assets/7bc7510fe41f/non_bootable_disk-03275585.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6d035553cd50/vmlinux-03275585.xz
kernel image: https://storage.googleapis.com/syzbot-assets/2fd7f855c25e/bzImage-03275585.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

BUG: KASAN: slab-use-after-free in drm_atomic_helper_wait_for_vblanks.part.0+0x77a/0x860 drivers/gpu/drm/drm_atomic_helper.c:1650
Read of size 1 at addr ffff888023f61009 by task kworker/u17:6/4248

CPU: 3 PID: 4248 Comm: kworker/u17:6 Not tainted 6.4.0-syzkaller-11472-g03275585cabd #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: events_unbound commit_work
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106
print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:364
print_report mm/kasan/report.c:475 [inline]
kasan_report+0x11d/0x130 mm/kasan/report.c:588
drm_atomic_helper_wait_for_vblanks.part.0+0x77a/0x860 drivers/gpu/drm/drm_atomic_helper.c:1650
drm_atomic_helper_wait_for_vblanks drivers/gpu/drm/drm_atomic_helper.c:1646 [inline]
drm_atomic_helper_commit_tail+0xc7/0xf0 drivers/gpu/drm/drm_atomic_helper.c:1746
commit_tail+0x32d/0x420 drivers/gpu/drm/drm_atomic_helper.c:1823
process_one_work+0xa34/0x16f0 kernel/workqueue.c:2597
worker_thread+0x67d/0x10c0 kernel/workqueue.c:2748
kthread+0x344/0x440 kernel/kthread.c:389
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>

Allocated by task 28853:
kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
____kasan_kmalloc mm/kasan/common.c:374 [inline]
____kasan_kmalloc mm/kasan/common.c:333 [inline]
__kasan_kmalloc+0xa2/0xb0 mm/kasan/common.c:383
kmalloc include/linux/slab.h:579 [inline]
drm_atomic_helper_crtc_duplicate_state+0x6f/0xc0 drivers/gpu/drm/drm_atomic_state_helper.c:177
drm_simple_kms_crtc_duplicate_state+0x8b/0xb0 drivers/gpu/drm/drm_simple_kms_helper.c:166
drm_atomic_get_crtc_state+0x179/0x470 drivers/gpu/drm/drm_atomic.c:353
page_flip_common+0x57/0x310 drivers/gpu/drm/drm_atomic_helper.c:3589
drm_atomic_helper_page_flip+0xb8/0x190 drivers/gpu/drm/drm_atomic_helper.c:3650
drm_mode_page_flip_ioctl+0xf20/0x12a0 drivers/gpu/drm/drm_plane.c:1373
drm_ioctl_kernel+0x281/0x4e0 drivers/gpu/drm/drm_ioctl.c:788
drm_ioctl+0x577/0xb30 drivers/gpu/drm/drm_ioctl.c:891
drm_compat_ioctl+0x375/0x4b0 drivers/gpu/drm/drm_ioc32.c:988
__do_compat_sys_ioctl+0x25b/0x2b0 fs/ioctl.c:968
do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
__do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
entry_SYSENTER_compat_after_hwframe+0x70/0x82

Freed by task 28850:
kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
____kasan_slab_free mm/kasan/common.c:236 [inline]
____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200
kasan_slab_free include/linux/kasan.h:162 [inline]
slab_free_hook mm/slub.c:1792 [inline]
slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1818
slab_free mm/slub.c:3801 [inline]
__kmem_cache_free+0xb8/0x2d0 mm/slub.c:3814
drm_simple_kms_crtc_destroy_state+0x8c/0xb0 drivers/gpu/drm/drm_simple_kms_helper.c:177
drm_atomic_state_default_clear+0x3a7/0xdd0 drivers/gpu/drm/drm_atomic.c:219
drm_atomic_state_clear drivers/gpu/drm/drm_atomic.c:288 [inline]
__drm_atomic_state_free+0x176/0x2b0 drivers/gpu/drm/drm_atomic.c:304
kref_put include/linux/kref.h:65 [inline]
drm_atomic_state_put include/drm/drm_atomic.h:490 [inline]
drm_client_modeset_commit_atomic+0x6b0/0x7e0 drivers/gpu/drm/drm_client_modeset.c:1051
drm_client_modeset_commit_locked+0x149/0x580 drivers/gpu/drm/drm_client_modeset.c:1148
drm_client_modeset_commit+0x51/0x80 drivers/gpu/drm/drm_client_modeset.c:1174
__drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:251 [inline]
__drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:230 [inline]
drm_fb_helper_restore_fbdev_mode_unlocked drivers/gpu/drm/drm_fb_helper.c:278 [inline]
drm_fb_helper_lastclose+0xc5/0x170 drivers/gpu/drm/drm_fb_helper.c:2005
drm_fbdev_generic_client_restore+0x2c/0x40 drivers/gpu/drm/drm_fbdev_generic.c:259
drm_client_dev_restore+0x188/0x290 drivers/gpu/drm/drm_client.c:236
drm_release+0x40d/0x4f0 drivers/gpu/drm/drm_file.c:497
__fput+0x40c/0xad0 fs/file_table.c:384
task_work_run+0x16f/0x270 kernel/task_work.c:179
resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
exit_to_user_mode_prepare+0x210/0x240 kernel/entry/common.c:204
__syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297
__do_fast_syscall_32+0x72/0xf0 arch/x86/entry/common.c:181
do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
entry_SYSENTER_compat_after_hwframe+0x70/0x82

Last potentially related work creation:
kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
__kasan_record_aux_stack+0xb9/0xd0 mm/kasan/generic.c:491
insert_work+0x48/0x360 kernel/workqueue.c:1553
__queue_work+0x625/0x1120 kernel/workqueue.c:1714
call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700
expire_timers+0xbc/0x4b0 kernel/time/timer.c:1746
__run_timers kernel/time/timer.c:2022 [inline]
__run_timers kernel/time/timer.c:1995 [inline]
run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
__do_softirq+0x1d4/0x905 kernel/softirq.c:553

Second to last potentially related work creation:
kasan_save_stack+0x22/0x40 mm/kasan/common.c:45
__kasan_record_aux_stack+0xb9/0xd0 mm/kasan/generic.c:491
insert_work+0x48/0x360 kernel/workqueue.c:1553
__queue_work+0x625/0x1120 kernel/workqueue.c:1714
call_timer_fn+0x1a0/0x580 kernel/time/timer.c:1700
expire_timers+0xbc/0x4b0 kernel/time/timer.c:1746
__run_timers kernel/time/timer.c:2022 [inline]
__run_timers kernel/time/timer.c:1995 [inline]
run_timer_softirq+0x326/0x910 kernel/time/timer.c:2035
__do_softirq+0x1d4/0x905 kernel/softirq.c:553

The buggy address belongs to the object at ffff888023f61000
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 9 bytes inside of
freed 512-byte region [ffff888023f61000, ffff888023f61200)

The buggy address belongs to the physical page:
page:ffffea00008fd800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x23f60
head:ffffea00008fd800 order:2 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000010200 ffff888012842c80 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 2572, tgid 2572 (kworker/u17:0), ts 13571791526, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1570
prep_new_page mm/page_alloc.c:1577 [inline]
get_page_from_freelist+0xfed/0x2d30 mm/page_alloc.c:3221
__alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4477
alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279
alloc_slab_page mm/slub.c:1862 [inline]
allocate_slab+0x25f/0x390 mm/slub.c:2009
new_slab mm/slub.c:2062 [inline]
___slab_alloc+0xbc3/0x15d0 mm/slub.c:3215
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3314
__slab_alloc_node mm/slub.c:3367 [inline]
slab_alloc_node mm/slub.c:3460 [inline]
__kmem_cache_alloc_node+0x143/0x350 mm/slub.c:3509
kmalloc_trace+0x26/0xe0 mm/slab_common.c:1076
kmalloc include/linux/slab.h:579 [inline]
kzalloc include/linux/slab.h:700 [inline]
alloc_bprm+0x51/0xba0 fs/exec.c:1513
kernel_execve+0xaf/0x500 fs/exec.c:1988
call_usermodehelper_exec_async+0x260/0x4e0 kernel/umh.c:110
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
page_owner free stack trace missing

Memory state around the buggy address:
ffff888023f60f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff888023f60f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888023f61000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff888023f61080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff888023f61100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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If the bug is already fixed, let syzbot know by replying with:
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(See the list of subsystem names on the web dashboard)

If the bug is a duplicate of another bug, reply with:
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If you want to undo deduplication, reply with:
#syz undup


2023-12-06 01:47:24

by lee bruce

[permalink] [raw]
Subject: Re: [syzbot] [dri?] KASAN: slab-use-after-free Read in drm_atomic_helper_wait_for_vblanks

Hello, I reproduced this bug with repro.c in
upstream kernel commit
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/?id=8182d7a3f1b8982c0136dca82a846ea375a4d6e9
kernel config https://syzkaller.appspot.com/text?tag=KernelConfig&x=32d0b9b42ceb8b10
the same configuration in dashboard
https://syzkaller.appspot.com/bug?extid=380dcf72caf0b5ef5537

=* repro.txt =*
r0 = syz_open_dev$dri(&(0x7f0000000080), 0xf2, 0x0)
ioctl$DRM_IOCTL_MODE_GETRESOURCES(r0, 0xc04064a0,
&(0x7f0000000180)={0x0, &(0x7f00000000c0)=[<r1=>0x0], 0x0, 0x0, 0x0,
0x1})
ioctl$DRM_IOCTL_MODE_GETCRTC(r0, 0xc06864a1, &(0x7f00000003c0)={0x0,
0x0, r1, <r2=>0x0})
r3 = syz_open_dev$dri(&(0x7f0000000080), 0xf2, 0x0)
ioctl$DRM_IOCTL_MODE_GETRESOURCES(r3, 0xc04064a0,
&(0x7f0000000180)={0x0, &(0x7f00000000c0)=[<r4=>0x0], 0x0, 0x0, 0x0,
0x1})
ioctl$DRM_IOCTL_MODE_PAGE_FLIP(r0, 0xc01864b0, &(0x7f0000000000)={r4,
r2, 0x0, 0x0, 0x80000003})


=* repro.c =*

#define _GNU_SOURCE

#include <arpa/inet.h>
#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <ifaddrs.h>
#include <linux/capability.h>
#include <linux/ethtool.h>
#include <linux/falloc.h>
#include <linux/genetlink.h>
#include <linux/if_addr.h>
#include <linux/if_ether.h>
#include <linux/if_link.h>
#include <linux/if_tun.h>
#include <linux/in6.h>
#include <linux/ip.h>
#include <linux/neighbour.h>
#include <linux/net.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
#include <linux/sockios.h>
#include <linux/tcp.h>
#include <linux/veth.h>
#include <net/if.h>
#include <net/if_arp.h>
#include <netinet/in.h>
#include <sched.h>
#include <setjmp.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/prctl.h>
#include <sys/resource.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/swap.h>
#include <sys/syscall.h>
#include <sys/time.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

static unsigned long long procid;

static __thread int clone_ongoing;
static __thread int skip_segv;
static __thread jmp_buf segv_env;

static void segv_handler(int sig, siginfo_t* info, void* ctx) {
if (__atomic_load_n(&clone_ongoing, __ATOMIC_RELAXED) != 0) {
exit(sig);
}
uintptr_t addr = (uintptr_t)info->si_addr;
const uintptr_t prog_start = 1 << 20;
const uintptr_t prog_end = 100 << 20;
int skip = __atomic_load_n(&skip_segv, __ATOMIC_RELAXED) != 0;
int valid = addr < prog_start || addr > prog_end;
if (skip && valid) {
_longjmp(segv_env, 1);
}
exit(sig);
}

static void install_segv_handler(void) {
struct sigaction sa;
memset(&sa, 0, sizeof(sa));
sa.sa_handler = SIG_IGN;
syscall(SYS_rt_sigaction, 0x20, &sa, NULL, 8);
syscall(SYS_rt_sigaction, 0x21, &sa, NULL, 8);
memset(&sa, 0, sizeof(sa));
sa.sa_sigaction = segv_handler;
sa.sa_flags = SA_NODEFER | SA_SIGINFO;
sigaction(SIGSEGV, &sa, NULL);
sigaction(SIGBUS, &sa, NULL);
}

#define NONFAILING(...) \
({ \
int ok = 1; \
__atomic_fetch_add(&skip_segv, 1, __ATOMIC_SEQ_CST); \
if (_setjmp(segv_env) == 0) { \
__VA_ARGS__; \
} else \
ok = 0; \
__atomic_fetch_sub(&skip_segv, 1, __ATOMIC_SEQ_CST); \
ok; \
})

static void sleep_ms(uint64_t ms) { usleep(ms * 1000); }

static uint64_t current_time_ms(void) {
struct timespec ts;
if (clock_gettime(CLOCK_MONOTONIC, &ts)) exit(1);
return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
}

static void use_temporary_dir(void) {
char tmpdir_template[] = "./syzkaller.XXXXXX";
char* tmpdir = mkdtemp(tmpdir_template);
if (!tmpdir) exit(1);
if (chmod(tmpdir, 0777)) exit(1);
if (chdir(tmpdir)) exit(1);
}

static bool write_file(const char* file, const char* what, ...) {
char buf[1024];
va_list args;
va_start(args, what);
vsnprintf(buf, sizeof(buf), what, args);
va_end(args);
buf[sizeof(buf) - 1] = 0;
int len = strlen(buf);
int fd = open(file, O_WRONLY | O_CLOEXEC);
if (fd == -1) return false;
if (write(fd, buf, len) != len) {
int err = errno;
close(fd);
errno = err;
return false;
}
close(fd);
return true;
}

struct nlmsg {
char* pos;
int nesting;
struct nlattr* nested[8];
char buf[4096];
};

static void netlink_init(struct nlmsg* nlmsg, int typ, int flags,
const void* data, int size) {
memset(nlmsg, 0, sizeof(*nlmsg));
struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
hdr->nlmsg_type = typ;
hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags;
memcpy(hdr + 1, data, size);
nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size);
}

static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data,
int size) {
struct nlattr* attr = (struct nlattr*)nlmsg->pos;
attr->nla_len = sizeof(*attr) + size;
attr->nla_type = typ;
if (size > 0) memcpy(attr + 1, data, size);
nlmsg->pos += NLMSG_ALIGN(attr->nla_len);
}

static void netlink_nest(struct nlmsg* nlmsg, int typ) {
struct nlattr* attr = (struct nlattr*)nlmsg->pos;
attr->nla_type = typ;
nlmsg->pos += sizeof(*attr);
nlmsg->nested[nlmsg->nesting++] = attr;
}

static void netlink_done(struct nlmsg* nlmsg) {
struct nlattr* attr = nlmsg->nested[--nlmsg->nesting];
attr->nla_len = nlmsg->pos - (char*)attr;
}

struct vf_intf {
char pass_thru_intf[IFNAMSIZ];
int ppid;
};

static struct vf_intf vf_intf;

static void find_vf_interface(void) {
struct ifaddrs* addresses = NULL;
int pid = getpid();
int ret = 0;
memset(&vf_intf, 0, sizeof(struct vf_intf));
if (getifaddrs(&addresses) == -1) {
return;
}
int fd = socket(AF_INET, SOCK_DGRAM, IPPROTO_IP);
if (fd < 0) {
return;
}
struct ifreq ifr;
struct ethtool_drvinfo drvinfo;
struct ifaddrs* address = addresses;
while (address) {
memset(&ifr, 0, sizeof(struct ifreq));
strcpy(ifr.ifr_name, address->ifa_name);
memset(&drvinfo, 0, sizeof(struct ethtool_drvinfo));
drvinfo.cmd = ETHTOOL_GDRVINFO;
ifr.ifr_data = (caddr_t)&drvinfo;
ret = ioctl(fd, SIOCETHTOOL, &ifr);
if (ret < 0) {
} else if (strlen(drvinfo.bus_info)) {
if (strcmp(drvinfo.bus_info, "0000:00:11.0") == 0) {
if (strlen(address->ifa_name) < IFNAMSIZ) {
strncpy(vf_intf.pass_thru_intf, address->ifa_name, IFNAMSIZ);
vf_intf.ppid = pid;
} else {
}
break;
}
}
address = address->ifa_next;
}
freeifaddrs(addresses);
if (!vf_intf.ppid) {
memset(&vf_intf, 0, sizeof(struct vf_intf));
return;
}
}

static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type,
int* reply_len, bool dofail) {
if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting) exit(1);
struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
hdr->nlmsg_len = nlmsg->pos - nlmsg->buf;
struct sockaddr_nl addr;
memset(&addr, 0, sizeof(addr));
addr.nl_family = AF_NETLINK;
ssize_t n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0,
(struct sockaddr*)&addr, sizeof(addr));
if (n != (ssize_t)hdr->nlmsg_len) {
if (dofail) exit(1);
return -1;
}
n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0);
if (reply_len) *reply_len = 0;
if (n < 0) {
if (dofail) exit(1);
return -1;
}
if (n < (ssize_t)sizeof(struct nlmsghdr)) {
errno = EINVAL;
if (dofail) exit(1);
return -1;
}
if (hdr->nlmsg_type == NLMSG_DONE) return 0;
if (reply_len && hdr->nlmsg_type == reply_type) {
*reply_len = n;
return 0;
}
if (n < (ssize_t)(sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))) {
errno = EINVAL;
if (dofail) exit(1);
return -1;
}
if (hdr->nlmsg_type != NLMSG_ERROR) {
errno = EINVAL;
if (dofail) exit(1);
return -1;
}
errno = -((struct nlmsgerr*)(hdr + 1))->error;
return -errno;
}

static int netlink_send(struct nlmsg* nlmsg, int sock) {
return netlink_send_ext(nlmsg, sock, 0, NULL, true);
}

static int netlink_query_family_id(struct nlmsg* nlmsg, int sock,
const char* family_name, bool dofail) {
struct genlmsghdr genlhdr;
memset(&genlhdr, 0, sizeof(genlhdr));
genlhdr.cmd = CTRL_CMD_GETFAMILY;
netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr));
netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, family_name,
strnlen(family_name, GENL_NAMSIZ - 1) + 1);
int n = 0;
int err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n, dofail);
if (err < 0) {
return -1;
}
uint16_t id = 0;
struct nlattr* attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN +
NLMSG_ALIGN(sizeof(genlhdr)));
for (; (char*)attr < nlmsg->buf + n;
attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
if (attr->nla_type == CTRL_ATTR_FAMILY_ID) {
id = *(uint16_t*)(attr + 1);
break;
}
}
if (!id) {
errno = EINVAL;
return -1;
}
recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0);
return id;
}

static int netlink_next_msg(struct nlmsg* nlmsg, unsigned int offset,
unsigned int total_len) {
struct nlmsghdr* hdr = (struct nlmsghdr*)(nlmsg->buf + offset);
if (offset == total_len || offset + hdr->nlmsg_len > total_len) return -1;
return hdr->nlmsg_len;
}

static void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type,
const char* name, bool up) {
struct ifinfomsg hdr;
memset(&hdr, 0, sizeof(hdr));
if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP;
netlink_init(nlmsg, RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr,
sizeof(hdr));
if (name) netlink_attr(nlmsg, IFLA_IFNAME, name, strlen(name));
netlink_nest(nlmsg, IFLA_LINKINFO);
netlink_attr(nlmsg, IFLA_INFO_KIND, type, strlen(type));
}

static void netlink_add_device(struct nlmsg* nlmsg, int sock, const char* type,
const char* name) {
netlink_add_device_impl(nlmsg, type, name, false);
netlink_done(nlmsg);
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_add_veth(struct nlmsg* nlmsg, int sock, const char* name,
const char* peer) {
netlink_add_device_impl(nlmsg, "veth", name, false);
netlink_nest(nlmsg, IFLA_INFO_DATA);
netlink_nest(nlmsg, VETH_INFO_PEER);
nlmsg->pos += sizeof(struct ifinfomsg);
netlink_attr(nlmsg, IFLA_IFNAME, peer, strlen(peer));
netlink_done(nlmsg);
netlink_done(nlmsg);
netlink_done(nlmsg);
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_add_xfrm(struct nlmsg* nlmsg, int sock, const char* name) {
netlink_add_device_impl(nlmsg, "xfrm", name, true);
netlink_nest(nlmsg, IFLA_INFO_DATA);
int if_id = 1;
netlink_attr(nlmsg, 2, &if_id, sizeof(if_id));
netlink_done(nlmsg);
netlink_done(nlmsg);
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_add_hsr(struct nlmsg* nlmsg, int sock, const char* name,
const char* slave1, const char* slave2) {
netlink_add_device_impl(nlmsg, "hsr", name, false);
netlink_nest(nlmsg, IFLA_INFO_DATA);
int ifindex1 = if_nametoindex(slave1);
netlink_attr(nlmsg, IFLA_HSR_SLAVE1, &ifindex1, sizeof(ifindex1));
int ifindex2 = if_nametoindex(slave2);
netlink_attr(nlmsg, IFLA_HSR_SLAVE2, &ifindex2, sizeof(ifindex2));
netlink_done(nlmsg);
netlink_done(nlmsg);
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_add_linked(struct nlmsg* nlmsg, int sock, const char* type,
const char* name, const char* link) {
netlink_add_device_impl(nlmsg, type, name, false);
netlink_done(nlmsg);
int ifindex = if_nametoindex(link);
netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_add_vlan(struct nlmsg* nlmsg, int sock, const char* name,
const char* link, uint16_t id, uint16_t proto) {
netlink_add_device_impl(nlmsg, "vlan", name, false);
netlink_nest(nlmsg, IFLA_INFO_DATA);
netlink_attr(nlmsg, IFLA_VLAN_ID, &id, sizeof(id));
netlink_attr(nlmsg, IFLA_VLAN_PROTOCOL, &proto, sizeof(proto));
netlink_done(nlmsg);
netlink_done(nlmsg);
int ifindex = if_nametoindex(link);
netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_add_macvlan(struct nlmsg* nlmsg, int sock, const char* name,
const char* link) {
netlink_add_device_impl(nlmsg, "macvlan", name, false);
netlink_nest(nlmsg, IFLA_INFO_DATA);
uint32_t mode = MACVLAN_MODE_BRIDGE;
netlink_attr(nlmsg, IFLA_MACVLAN_MODE, &mode, sizeof(mode));
netlink_done(nlmsg);
netlink_done(nlmsg);
int ifindex = if_nametoindex(link);
netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_add_geneve(struct nlmsg* nlmsg, int sock, const char* name,
uint32_t vni, struct in_addr* addr4,
struct in6_addr* addr6) {
netlink_add_device_impl(nlmsg, "geneve", name, false);
netlink_nest(nlmsg, IFLA_INFO_DATA);
netlink_attr(nlmsg, IFLA_GENEVE_ID, &vni, sizeof(vni));
if (addr4) netlink_attr(nlmsg, IFLA_GENEVE_REMOTE, addr4, sizeof(*addr4));
if (addr6) netlink_attr(nlmsg, IFLA_GENEVE_REMOTE6, addr6, sizeof(*addr6));
netlink_done(nlmsg);
netlink_done(nlmsg);
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

#define IFLA_IPVLAN_FLAGS 2
#define IPVLAN_MODE_L3S 2
#undef IPVLAN_F_VEPA
#define IPVLAN_F_VEPA 2

static void netlink_add_ipvlan(struct nlmsg* nlmsg, int sock, const char* name,
const char* link, uint16_t mode,
uint16_t flags) {
netlink_add_device_impl(nlmsg, "ipvlan", name, false);
netlink_nest(nlmsg, IFLA_INFO_DATA);
netlink_attr(nlmsg, IFLA_IPVLAN_MODE, &mode, sizeof(mode));
netlink_attr(nlmsg, IFLA_IPVLAN_FLAGS, &flags, sizeof(flags));
netlink_done(nlmsg);
netlink_done(nlmsg);
int ifindex = if_nametoindex(link);
netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static void netlink_device_change(struct nlmsg* nlmsg, int sock,
const char* name, bool up, const char* master,
const void* mac, int macsize,
const char* new_name) {
struct ifinfomsg hdr;
memset(&hdr, 0, sizeof(hdr));
if (up) hdr.ifi_flags = hdr.ifi_change = IFF_UP;
hdr.ifi_index = if_nametoindex(name);
netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr));
if (new_name) netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name));
if (master) {
int ifindex = if_nametoindex(master);
netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex));
}
if (macsize) netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize);
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static int netlink_add_addr(struct nlmsg* nlmsg, int sock, const char* dev,
const void* addr, int addrsize) {
struct ifaddrmsg hdr;
memset(&hdr, 0, sizeof(hdr));
hdr.ifa_family = addrsize == 4 ? AF_INET : AF_INET6;
hdr.ifa_prefixlen = addrsize == 4 ? 24 : 120;
hdr.ifa_scope = RT_SCOPE_UNIVERSE;
hdr.ifa_index = if_nametoindex(dev);
netlink_init(nlmsg, RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr,
sizeof(hdr));
netlink_attr(nlmsg, IFA_LOCAL, addr, addrsize);
netlink_attr(nlmsg, IFA_ADDRESS, addr, addrsize);
return netlink_send(nlmsg, sock);
}

static void netlink_add_addr4(struct nlmsg* nlmsg, int sock, const char* dev,
const char* addr) {
struct in_addr in_addr;
inet_pton(AF_INET, addr, &in_addr);
int err = netlink_add_addr(nlmsg, sock, dev, &in_addr, sizeof(in_addr));
if (err < 0) {
}
}

static void netlink_add_addr6(struct nlmsg* nlmsg, int sock, const char* dev,
const char* addr) {
struct in6_addr in6_addr;
inet_pton(AF_INET6, addr, &in6_addr);
int err = netlink_add_addr(nlmsg, sock, dev, &in6_addr, sizeof(in6_addr));
if (err < 0) {
}
}

static void netlink_add_neigh(struct nlmsg* nlmsg, int sock, const char* name,
const void* addr, int addrsize, const void* mac,
int macsize) {
struct ndmsg hdr;
memset(&hdr, 0, sizeof(hdr));
hdr.ndm_family = addrsize == 4 ? AF_INET : AF_INET6;
hdr.ndm_ifindex = if_nametoindex(name);
hdr.ndm_state = NUD_PERMANENT;
netlink_init(nlmsg, RTM_NEWNEIGH, NLM_F_EXCL | NLM_F_CREATE, &hdr,
sizeof(hdr));
netlink_attr(nlmsg, NDA_DST, addr, addrsize);
netlink_attr(nlmsg, NDA_LLADDR, mac, macsize);
int err = netlink_send(nlmsg, sock);
if (err < 0) {
}
}

static struct nlmsg nlmsg;

static int tunfd = -1;

#define TUN_IFACE "syz_tun"
#define LOCAL_MAC 0xaaaaaaaaaaaa
#define REMOTE_MAC 0xaaaaaaaaaabb
#define LOCAL_IPV4 "172.20.20.170"
#define REMOTE_IPV4 "172.20.20.187"
#define LOCAL_IPV6 "fe80::aa"
#define REMOTE_IPV6 "fe80::bb"

#define IFF_NAPI 0x0010

static void initialize_tun(void) {
tunfd = open("/dev/net/tun", O_RDWR | O_NONBLOCK);
if (tunfd == -1) {
printf("tun: can't open /dev/net/tun: please enable CONFIG_TUN=y\n");
printf("otherwise fuzzing or reproducing might not work as intended\n");
return;
}
const int kTunFd = 200;
if (dup2(tunfd, kTunFd) < 0) exit(1);
close(tunfd);
tunfd = kTunFd;
struct ifreq ifr;
memset(&ifr, 0, sizeof(ifr));
strncpy(ifr.ifr_name, TUN_IFACE, IFNAMSIZ);
ifr.ifr_flags = IFF_TAP | IFF_NO_PI;
if (ioctl(tunfd, TUNSETIFF, (void*)&ifr) < 0) {
exit(1);
}
char sysctl[64];
sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/accept_dad", TUN_IFACE);
write_file(sysctl, "0");
sprintf(sysctl, "/proc/sys/net/ipv6/conf/%s/router_solicitations", TUN_IFACE);
write_file(sysctl, "0");
int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (sock == -1) exit(1);
netlink_add_addr4(&nlmsg, sock, TUN_IFACE, LOCAL_IPV4);
netlink_add_addr6(&nlmsg, sock, TUN_IFACE, LOCAL_IPV6);
uint64_t macaddr = REMOTE_MAC;
struct in_addr in_addr;
inet_pton(AF_INET, REMOTE_IPV4, &in_addr);
netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in_addr, sizeof(in_addr),
&macaddr, ETH_ALEN);
struct in6_addr in6_addr;
inet_pton(AF_INET6, REMOTE_IPV6, &in6_addr);
netlink_add_neigh(&nlmsg, sock, TUN_IFACE, &in6_addr, sizeof(in6_addr),
&macaddr, ETH_ALEN);
macaddr = LOCAL_MAC;
netlink_device_change(&nlmsg, sock, TUN_IFACE, true, 0, &macaddr, ETH_ALEN,
NULL);
close(sock);
}

const int kInitNetNsFd = 201;

#define DEVLINK_FAMILY_NAME "devlink"

#define DEVLINK_CMD_PORT_GET 5
#define DEVLINK_CMD_RELOAD 37
#define DEVLINK_ATTR_BUS_NAME 1
#define DEVLINK_ATTR_DEV_NAME 2
#define DEVLINK_ATTR_NETDEV_NAME 7
#define DEVLINK_ATTR_NETNS_FD 138

static void netlink_devlink_netns_move(const char* bus_name,
const char* dev_name, int netns_fd) {
struct genlmsghdr genlhdr;
int sock;
int id, err;
sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
if (sock == -1) exit(1);
id = netlink_query_family_id(&nlmsg, sock, DEVLINK_FAMILY_NAME, true);
if (id == -1) goto error;
memset(&genlhdr, 0, sizeof(genlhdr));
genlhdr.cmd = DEVLINK_CMD_RELOAD;
netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr));
netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1);
netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1);
netlink_attr(&nlmsg, DEVLINK_ATTR_NETNS_FD, &netns_fd, sizeof(netns_fd));
err = netlink_send(&nlmsg, sock);
if (err < 0) {
}
error:
close(sock);
}

static struct nlmsg nlmsg2;

static void initialize_devlink_ports(const char* bus_name, const char* dev_name,
const char* netdev_prefix) {
struct genlmsghdr genlhdr;
int len, total_len, id, err, offset;
uint16_t netdev_index;
int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
if (sock == -1) exit(1);
int rtsock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (rtsock == -1) exit(1);
id = netlink_query_family_id(&nlmsg, sock, DEVLINK_FAMILY_NAME, true);
if (id == -1) goto error;
memset(&genlhdr, 0, sizeof(genlhdr));
genlhdr.cmd = DEVLINK_CMD_PORT_GET;
netlink_init(&nlmsg, id, NLM_F_DUMP, &genlhdr, sizeof(genlhdr));
netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1);
netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1);
err = netlink_send_ext(&nlmsg, sock, id, &total_len, true);
if (err < 0) {
goto error;
}
offset = 0;
netdev_index = 0;
while ((len = netlink_next_msg(&nlmsg, offset, total_len)) != -1) {
struct nlattr* attr = (struct nlattr*)(nlmsg.buf + offset + NLMSG_HDRLEN +
NLMSG_ALIGN(sizeof(genlhdr)));
for (; (char*)attr < nlmsg.buf + offset + len;
attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
if (attr->nla_type == DEVLINK_ATTR_NETDEV_NAME) {
char* port_name;
char netdev_name[IFNAMSIZ];
port_name = (char*)(attr + 1);
snprintf(netdev_name, sizeof(netdev_name), "%s%d", netdev_prefix,
netdev_index);
netlink_device_change(&nlmsg2, rtsock, port_name, true, 0, 0, 0,
netdev_name);
break;
}
}
offset += len;
netdev_index++;
}
error:
close(rtsock);
close(sock);
}

static void initialize_devlink_pci(void) {
int netns = open("/proc/self/ns/net", O_RDONLY);
if (netns == -1) exit(1);
int ret = setns(kInitNetNsFd, 0);
if (ret == -1) exit(1);
netlink_devlink_netns_move("pci", "0000:00:10.0", netns);
ret = setns(netns, 0);
if (ret == -1) exit(1);
close(netns);
initialize_devlink_ports("pci", "0000:00:10.0", "netpci");
}

static int runcmdline(char* cmdline) {
int ret = system(cmdline);
if (ret) {
}
return ret;
}

#define DEV_IPV4 "172.20.20.%d"
#define DEV_IPV6 "fe80::%02x"
#define DEV_MAC 0x00aaaaaaaaaa

static void netdevsim_add(unsigned int addr, unsigned int port_count) {
write_file("/sys/bus/netdevsim/del_device", "%u", addr);
if (write_file("/sys/bus/netdevsim/new_device", "%u %u", addr, port_count)) {
char buf[32];
snprintf(buf, sizeof(buf), "netdevsim%d", addr);
initialize_devlink_ports("netdevsim", buf, "netdevsim");
}
}

#define WG_GENL_NAME "wireguard"
enum wg_cmd {
WG_CMD_GET_DEVICE,
WG_CMD_SET_DEVICE,
};
enum wgdevice_attribute {
WGDEVICE_A_UNSPEC,
WGDEVICE_A_IFINDEX,
WGDEVICE_A_IFNAME,
WGDEVICE_A_PRIVATE_KEY,
WGDEVICE_A_PUBLIC_KEY,
WGDEVICE_A_FLAGS,
WGDEVICE_A_LISTEN_PORT,
WGDEVICE_A_FWMARK,
WGDEVICE_A_PEERS,
};
enum wgpeer_attribute {
WGPEER_A_UNSPEC,
WGPEER_A_PUBLIC_KEY,
WGPEER_A_PRESHARED_KEY,
WGPEER_A_FLAGS,
WGPEER_A_ENDPOINT,
WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
WGPEER_A_LAST_HANDSHAKE_TIME,
WGPEER_A_RX_BYTES,
WGPEER_A_TX_BYTES,
WGPEER_A_ALLOWEDIPS,
WGPEER_A_PROTOCOL_VERSION,
};
enum wgallowedip_attribute {
WGALLOWEDIP_A_UNSPEC,
WGALLOWEDIP_A_FAMILY,
WGALLOWEDIP_A_IPADDR,
WGALLOWEDIP_A_CIDR_MASK,
};

static void netlink_wireguard_setup(void) {
const char ifname_a[] = "wg0";
const char ifname_b[] = "wg1";
const char ifname_c[] = "wg2";
const char private_a[] =
"\xa0\x5c\xa8\x4f\x6c\x9c\x8e\x38\x53\xe2\xfd\x7a\x70\xae\x0f\xb2\x0f\xa1"
"\x52\x60\x0c\xb0\x08\x45\x17\x4f\x08\x07\x6f\x8d\x78\x43";
const char private_b[] =
"\xb0\x80\x73\xe8\xd4\x4e\x91\xe3\xda\x92\x2c\x22\x43\x82\x44\xbb\x88\x5c"
"\x69\xe2\x69\xc8\xe9\xd8\x35\xb1\x14\x29\x3a\x4d\xdc\x6e";
const char private_c[] =
"\xa0\xcb\x87\x9a\x47\xf5\xbc\x64\x4c\x0e\x69\x3f\xa6\xd0\x31\xc7\x4a\x15"
"\x53\xb6\xe9\x01\xb9\xff\x2f\x51\x8c\x78\x04\x2f\xb5\x42";
const char public_a[] =
"\x97\x5c\x9d\x81\xc9\x83\xc8\x20\x9e\xe7\x81\x25\x4b\x89\x9f\x8e\xd9\x25"
"\xae\x9f\x09\x23\xc2\x3c\x62\xf5\x3c\x57\xcd\xbf\x69\x1c";
const char public_b[] =
"\xd1\x73\x28\x99\xf6\x11\xcd\x89\x94\x03\x4d\x7f\x41\x3d\xc9\x57\x63\x0e"
"\x54\x93\xc2\x85\xac\xa4\x00\x65\xcb\x63\x11\xbe\x69\x6b";
const char public_c[] =
"\xf4\x4d\xa3\x67\xa8\x8e\xe6\x56\x4f\x02\x02\x11\x45\x67\x27\x08\x2f\x5c"
"\xeb\xee\x8b\x1b\xf5\xeb\x73\x37\x34\x1b\x45\x9b\x39\x22";
const uint16_t listen_a = 20001;
const uint16_t listen_b = 20002;
const uint16_t listen_c = 20003;
const uint16_t af_inet = AF_INET;
const uint16_t af_inet6 = AF_INET6;
const struct sockaddr_in endpoint_b_v4 = {
.sin_family = AF_INET,
.sin_port = htons(listen_b),
.sin_addr = {htonl(INADDR_LOOPBACK)}};
const struct sockaddr_in endpoint_c_v4 = {
.sin_family = AF_INET,
.sin_port = htons(listen_c),
.sin_addr = {htonl(INADDR_LOOPBACK)}};
struct sockaddr_in6 endpoint_a_v6 = {.sin6_family = AF_INET6,
.sin6_port = htons(listen_a)};
endpoint_a_v6.sin6_addr = in6addr_loopback;
struct sockaddr_in6 endpoint_c_v6 = {.sin6_family = AF_INET6,
.sin6_port = htons(listen_c)};
endpoint_c_v6.sin6_addr = in6addr_loopback;
const struct in_addr first_half_v4 = {0};
const struct in_addr second_half_v4 = {(uint32_t)htonl(128 << 24)};
const struct in6_addr first_half_v6 = {{{0}}};
const struct in6_addr second_half_v6 = {{{0x80}}};
const uint8_t half_cidr = 1;
const uint16_t persistent_keepalives[] = {1, 3, 7, 9, 14, 19};
struct genlmsghdr genlhdr = {.cmd = WG_CMD_SET_DEVICE, .version = 1};
int sock;
int id, err;
sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
if (sock == -1) {
return;
}
id = netlink_query_family_id(&nlmsg, sock, WG_GENL_NAME, true);
if (id == -1) goto error;
netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr));
netlink_attr(&nlmsg, WGDEVICE_A_IFNAME, ifname_a, strlen(ifname_a) + 1);
netlink_attr(&nlmsg, WGDEVICE_A_PRIVATE_KEY, private_a, 32);
netlink_attr(&nlmsg, WGDEVICE_A_LISTEN_PORT, &listen_a, 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGDEVICE_A_PEERS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_b, 32);
netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_b_v4,
sizeof(endpoint_b_v4));
netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
&persistent_keepalives[0], 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v4,
sizeof(first_half_v4));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v6,
sizeof(first_half_v6));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_c, 32);
netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_c_v6,
sizeof(endpoint_c_v6));
netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
&persistent_keepalives[1], 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v4,
sizeof(second_half_v4));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v6,
sizeof(second_half_v6));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
err = netlink_send(&nlmsg, sock);
if (err < 0) {
}
netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr));
netlink_attr(&nlmsg, WGDEVICE_A_IFNAME, ifname_b, strlen(ifname_b) + 1);
netlink_attr(&nlmsg, WGDEVICE_A_PRIVATE_KEY, private_b, 32);
netlink_attr(&nlmsg, WGDEVICE_A_LISTEN_PORT, &listen_b, 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGDEVICE_A_PEERS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_a, 32);
netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_a_v6,
sizeof(endpoint_a_v6));
netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
&persistent_keepalives[2], 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v4,
sizeof(first_half_v4));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v6,
sizeof(first_half_v6));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_c, 32);
netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_c_v4,
sizeof(endpoint_c_v4));
netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
&persistent_keepalives[3], 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v4,
sizeof(second_half_v4));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v6,
sizeof(second_half_v6));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
err = netlink_send(&nlmsg, sock);
if (err < 0) {
}
netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr));
netlink_attr(&nlmsg, WGDEVICE_A_IFNAME, ifname_c, strlen(ifname_c) + 1);
netlink_attr(&nlmsg, WGDEVICE_A_PRIVATE_KEY, private_c, 32);
netlink_attr(&nlmsg, WGDEVICE_A_LISTEN_PORT, &listen_c, 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGDEVICE_A_PEERS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_a, 32);
netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_a_v6,
sizeof(endpoint_a_v6));
netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
&persistent_keepalives[4], 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v4,
sizeof(first_half_v4));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &first_half_v6,
sizeof(first_half_v6));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGPEER_A_PUBLIC_KEY, public_b, 32);
netlink_attr(&nlmsg, WGPEER_A_ENDPOINT, &endpoint_b_v4,
sizeof(endpoint_b_v4));
netlink_attr(&nlmsg, WGPEER_A_PERSISTENT_KEEPALIVE_INTERVAL,
&persistent_keepalives[5], 2);
netlink_nest(&nlmsg, NLA_F_NESTED | WGPEER_A_ALLOWEDIPS);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v4,
sizeof(second_half_v4));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_nest(&nlmsg, NLA_F_NESTED | 0);
netlink_attr(&nlmsg, WGALLOWEDIP_A_FAMILY, &af_inet6, 2);
netlink_attr(&nlmsg, WGALLOWEDIP_A_IPADDR, &second_half_v6,
sizeof(second_half_v6));
netlink_attr(&nlmsg, WGALLOWEDIP_A_CIDR_MASK, &half_cidr, 1);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
netlink_done(&nlmsg);
err = netlink_send(&nlmsg, sock);
if (err < 0) {
}

error:
close(sock);
}

static void netlink_nicvf_setup(void) {
char cmdline[256];
if (!vf_intf.ppid) return;
sprintf(cmdline, "nsenter -t 1 -n ip link set %s netns %d",
vf_intf.pass_thru_intf, getpid());
if (runcmdline(cmdline)) return;
sprintf(cmdline, "ip a s %s", vf_intf.pass_thru_intf);
if (runcmdline(cmdline)) return;
sprintf(cmdline, "ip link set %s down", vf_intf.pass_thru_intf);
if (runcmdline(cmdline)) return;
sprintf(cmdline, "ip link set %s name nicvf0", vf_intf.pass_thru_intf);
if (runcmdline(cmdline)) return;
}
static void initialize_netdevices(void) {
char netdevsim[16];
sprintf(netdevsim, "netdevsim%d", (int)procid);
struct {
const char* type;
const char* dev;
} devtypes[] = {
{"ip6gretap", "ip6gretap0"}, {"bridge", "bridge0"}, {"vcan", "vcan0"},
{"bond", "bond0"}, {"team", "team0"}, {"dummy", "dummy0"},
{"nicvf", "nicvf0"}, {"nlmon", "nlmon0"}, {"caif", "caif0"},
{"batadv", "batadv0"}, {"vxcan", "vxcan1"}, {"veth", 0},
{"wireguard", "wg0"}, {"wireguard", "wg1"}, {"wireguard", "wg2"},
};
const char* devmasters[] = {"bridge", "bond", "team", "batadv"};
struct {
const char* name;
int macsize;
bool noipv6;
} devices[] = {
{"lo", ETH_ALEN},
{"sit0", 0},
{"bridge0", ETH_ALEN},
{"vcan0", 0, true},
{"tunl0", 0},
{"gre0", 0},
{"gretap0", ETH_ALEN},
{"ip_vti0", 0},
{"ip6_vti0", 0},
{"ip6tnl0", 0},
{"ip6gre0", 0},
{"ip6gretap0", ETH_ALEN},
{"erspan0", ETH_ALEN},
{"bond0", ETH_ALEN},
{"veth0", ETH_ALEN},
{"veth1", ETH_ALEN},
{"team0", ETH_ALEN},
{"veth0_to_bridge", ETH_ALEN},
{"veth1_to_bridge", ETH_ALEN},
{"veth0_to_bond", ETH_ALEN},
{"veth1_to_bond", ETH_ALEN},
{"veth0_to_team", ETH_ALEN},
{"veth1_to_team", ETH_ALEN},
{"veth0_to_hsr", ETH_ALEN},
{"veth1_to_hsr", ETH_ALEN},
{"hsr0", 0},
{"dummy0", ETH_ALEN},
{"nicvf0", 0, true},
{"nlmon0", 0},
{"vxcan0", 0, true},
{"vxcan1", 0, true},
{"caif0", ETH_ALEN},
{"batadv0", ETH_ALEN},
{netdevsim, ETH_ALEN},
{"xfrm0", ETH_ALEN},
{"veth0_virt_wifi", ETH_ALEN},
{"veth1_virt_wifi", ETH_ALEN},
{"virt_wifi0", ETH_ALEN},
{"veth0_vlan", ETH_ALEN},
{"veth1_vlan", ETH_ALEN},
{"vlan0", ETH_ALEN},
{"vlan1", ETH_ALEN},
{"macvlan0", ETH_ALEN},
{"macvlan1", ETH_ALEN},
{"ipvlan0", ETH_ALEN},
{"ipvlan1", ETH_ALEN},
{"veth0_macvtap", ETH_ALEN},
{"veth1_macvtap", ETH_ALEN},
{"macvtap0", ETH_ALEN},
{"macsec0", ETH_ALEN},
{"veth0_to_batadv", ETH_ALEN},
{"veth1_to_batadv", ETH_ALEN},
{"batadv_slave_0", ETH_ALEN},
{"batadv_slave_1", ETH_ALEN},
{"geneve0", ETH_ALEN},
{"geneve1", ETH_ALEN},
{"wg0", 0},
{"wg1", 0},
{"wg2", 0},
};
int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (sock == -1) exit(1);
unsigned i;
for (i = 0; i < sizeof(devtypes) / sizeof(devtypes[0]); i++)
netlink_add_device(&nlmsg, sock, devtypes[i].type, devtypes[i].dev);
for (i = 0; i < sizeof(devmasters) / (sizeof(devmasters[0])); i++) {
char master[32], slave0[32], veth0[32], slave1[32], veth1[32];
sprintf(slave0, "%s_slave_0", devmasters[i]);
sprintf(veth0, "veth0_to_%s", devmasters[i]);
netlink_add_veth(&nlmsg, sock, slave0, veth0);
sprintf(slave1, "%s_slave_1", devmasters[i]);
sprintf(veth1, "veth1_to_%s", devmasters[i]);
netlink_add_veth(&nlmsg, sock, slave1, veth1);
sprintf(master, "%s0", devmasters[i]);
netlink_device_change(&nlmsg, sock, slave0, false, master, 0, 0, NULL);
netlink_device_change(&nlmsg, sock, slave1, false, master, 0, 0, NULL);
}
netlink_add_xfrm(&nlmsg, sock, "xfrm0");
netlink_device_change(&nlmsg, sock, "bridge_slave_0", true, 0, 0, 0, NULL);
netlink_device_change(&nlmsg, sock, "bridge_slave_1", true, 0, 0, 0, NULL);
netlink_add_veth(&nlmsg, sock, "hsr_slave_0", "veth0_to_hsr");
netlink_add_veth(&nlmsg, sock, "hsr_slave_1", "veth1_to_hsr");
netlink_add_hsr(&nlmsg, sock, "hsr0", "hsr_slave_0", "hsr_slave_1");
netlink_device_change(&nlmsg, sock, "hsr_slave_0", true, 0, 0, 0, NULL);
netlink_device_change(&nlmsg, sock, "hsr_slave_1", true, 0, 0, 0, NULL);
netlink_add_veth(&nlmsg, sock, "veth0_virt_wifi", "veth1_virt_wifi");
netlink_add_linked(&nlmsg, sock, "virt_wifi", "virt_wifi0",
"veth1_virt_wifi");
netlink_add_veth(&nlmsg, sock, "veth0_vlan", "veth1_vlan");
netlink_add_vlan(&nlmsg, sock, "vlan0", "veth0_vlan", 0, htons(ETH_P_8021Q));
netlink_add_vlan(&nlmsg, sock, "vlan1", "veth0_vlan", 1, htons(ETH_P_8021AD));
netlink_add_macvlan(&nlmsg, sock, "macvlan0", "veth1_vlan");
netlink_add_macvlan(&nlmsg, sock, "macvlan1", "veth1_vlan");
netlink_add_ipvlan(&nlmsg, sock, "ipvlan0", "veth0_vlan", IPVLAN_MODE_L2, 0);
netlink_add_ipvlan(&nlmsg, sock, "ipvlan1", "veth0_vlan", IPVLAN_MODE_L3S,
IPVLAN_F_VEPA);
netlink_add_veth(&nlmsg, sock, "veth0_macvtap", "veth1_macvtap");
netlink_add_linked(&nlmsg, sock, "macvtap", "macvtap0", "veth0_macvtap");
netlink_add_linked(&nlmsg, sock, "macsec", "macsec0", "veth1_macvtap");
char addr[32];
sprintf(addr, DEV_IPV4, 14 + 10);
struct in_addr geneve_addr4;
if (inet_pton(AF_INET, addr, &geneve_addr4) <= 0) exit(1);
struct in6_addr geneve_addr6;
if (inet_pton(AF_INET6, "fc00::01", &geneve_addr6) <= 0) exit(1);
netlink_add_geneve(&nlmsg, sock, "geneve0", 0, &geneve_addr4, 0);
netlink_add_geneve(&nlmsg, sock, "geneve1", 1, 0, &geneve_addr6);
netdevsim_add((int)procid, 4);
netlink_wireguard_setup();
netlink_nicvf_setup();
for (i = 0; i < sizeof(devices) / (sizeof(devices[0])); i++) {
char addr[32];
sprintf(addr, DEV_IPV4, i + 10);
netlink_add_addr4(&nlmsg, sock, devices[i].name, addr);
if (!devices[i].noipv6) {
sprintf(addr, DEV_IPV6, i + 10);
netlink_add_addr6(&nlmsg, sock, devices[i].name, addr);
}
uint64_t macaddr = DEV_MAC + ((i + 10ull) << 40);
netlink_device_change(&nlmsg, sock, devices[i].name, true, 0, &macaddr,
devices[i].macsize, NULL);
}
close(sock);
}
static void initialize_netdevices_init(void) {
int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
if (sock == -1) exit(1);
struct {
const char* type;
int macsize;
bool noipv6;
bool noup;
} devtypes[] = {
{"nr", 7, true},
{"rose", 5, true, true},
};
unsigned i;
for (i = 0; i < sizeof(devtypes) / sizeof(devtypes[0]); i++) {
char dev[32], addr[32];
sprintf(dev, "%s%d", devtypes[i].type, (int)procid);
sprintf(addr, "172.30.%d.%d", i, (int)procid + 1);
netlink_add_addr4(&nlmsg, sock, dev, addr);
if (!devtypes[i].noipv6) {
sprintf(addr, "fe88::%02x:%02x", i, (int)procid + 1);
netlink_add_addr6(&nlmsg, sock, dev, addr);
}
int macsize = devtypes[i].macsize;
uint64_t macaddr = 0xbbbbbb +
((unsigned long long)i << (8 * (macsize - 2))) +
(procid << (8 * (macsize - 1)));
netlink_device_change(&nlmsg, sock, dev, !devtypes[i].noup, 0, &macaddr,
macsize, NULL);
}
close(sock);
find_vf_interface();
}

static int read_tun(char* data, int size) {
if (tunfd < 0) return -1;
int rv = read(tunfd, data, size);
if (rv < 0) {
if (errno == EAGAIN || errno == EBADFD) return -1;
exit(1);
}
return rv;
}

static void flush_tun() {
char data[1000];
while (read_tun(&data[0], sizeof(data)) != -1) {
}
}

#define MAX_FDS 30

static long syz_open_dev(volatile long a0, volatile long a1, volatile long a2) {
if (a0 == 0xc || a0 == 0xb) {
char buf[128];
sprintf(buf, "/dev/%s/%d:%d", a0 == 0xc ? "char" : "block", (uint8_t)a1,
(uint8_t)a2);
return open(buf, O_RDWR, 0);
} else {
char buf[1024];
char* hash;
strncpy(buf, (char*)a0, sizeof(buf) - 1);
buf[sizeof(buf) - 1] = 0;
while ((hash = strchr(buf, '#'))) {
*hash = '0' + (char)(a1 % 10);
a1 /= 10;
}
return open(buf, a2, 0);
}
}

static void setup_common() {
if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) {
}
}

static void setup_binderfs() {
if (mkdir("/dev/binderfs", 0777)) {
}
if (mount("binder", "/dev/binderfs", "binder", 0, NULL)) {
}
}

static void loop();

static void sandbox_common() {
prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
setsid();
int netns = open("/proc/self/ns/net", O_RDONLY);
if (netns == -1) exit(1);
if (dup2(netns, kInitNetNsFd) < 0) exit(1);
close(netns);
struct rlimit rlim;
rlim.rlim_cur = rlim.rlim_max = (200 << 20);
setrlimit(RLIMIT_AS, &rlim);
rlim.rlim_cur = rlim.rlim_max = 32 << 20;
setrlimit(RLIMIT_MEMLOCK, &rlim);
rlim.rlim_cur = rlim.rlim_max = 136 << 20;
setrlimit(RLIMIT_FSIZE, &rlim);
rlim.rlim_cur = rlim.rlim_max = 1 << 20;
setrlimit(RLIMIT_STACK, &rlim);
rlim.rlim_cur = rlim.rlim_max = 128 << 20;
setrlimit(RLIMIT_CORE, &rlim);
rlim.rlim_cur = rlim.rlim_max = 256;
setrlimit(RLIMIT_NOFILE, &rlim);
if (unshare(CLONE_NEWNS)) {
}
if (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
}
if (unshare(CLONE_NEWIPC)) {
}
if (unshare(0x02000000)) {
}
if (unshare(CLONE_NEWUTS)) {
}
if (unshare(CLONE_SYSVSEM)) {
}
typedef struct {
const char* name;
const char* value;
} sysctl_t;
static const sysctl_t sysctls[] = {
{"/proc/sys/kernel/shmmax", "16777216"},
{"/proc/sys/kernel/shmall", "536870912"},
{"/proc/sys/kernel/shmmni", "1024"},
{"/proc/sys/kernel/msgmax", "8192"},
{"/proc/sys/kernel/msgmni", "1024"},
{"/proc/sys/kernel/msgmnb", "1024"},
{"/proc/sys/kernel/sem", "1024 1048576 500 1024"},
};
unsigned i;
for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++)
write_file(sysctls[i].name, sysctls[i].value);
}

static int wait_for_loop(int pid) {
if (pid < 0) exit(1);
int status = 0;
while (waitpid(-1, &status, __WALL) != pid) {
}
return WEXITSTATUS(status);
}

static void drop_caps(void) {
struct __user_cap_header_struct cap_hdr = {};
struct __user_cap_data_struct cap_data[2] = {};
cap_hdr.version = _LINUX_CAPABILITY_VERSION_3;
cap_hdr.pid = getpid();
if (syscall(SYS_capget, &cap_hdr, &cap_data)) exit(1);
const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE);
cap_data[0].effective &= ~drop;
cap_data[0].permitted &= ~drop;
cap_data[0].inheritable &= ~drop;
if (syscall(SYS_capset, &cap_hdr, &cap_data)) exit(1);
}

static int do_sandbox_none(void) {
if (unshare(CLONE_NEWPID)) {
}
int pid = fork();
if (pid != 0) return wait_for_loop(pid);
setup_common();
sandbox_common();
drop_caps();
initialize_netdevices_init();
if (unshare(CLONE_NEWNET)) {
}
write_file("/proc/sys/net/ipv4/ping_group_range", "0 65535");
initialize_devlink_pci();
initialize_tun();
initialize_netdevices();
setup_binderfs();
loop();
exit(1);
}

#define FS_IOC_SETFLAGS _IOW('f', 2, long)
static void remove_dir(const char* dir) {
int iter = 0;
DIR* dp = 0;
retry:
while (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) {
}
dp = opendir(dir);
if (dp == NULL) {
if (errno == EMFILE) {
exit(1);
}
exit(1);
}
struct dirent* ep = 0;
while ((ep = readdir(dp))) {
if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0) continue;
char filename[FILENAME_MAX];
snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name);
while (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW) == 0) {
}
struct stat st;
if (lstat(filename, &st)) exit(1);
if (S_ISDIR(st.st_mode)) {
remove_dir(filename);
continue;
}
int i;
for (i = 0;; i++) {
if (unlink(filename) == 0) break;
if (errno == EPERM) {
int fd = open(filename, O_RDONLY);
if (fd != -1) {
long flags = 0;
if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
}
close(fd);
continue;
}
}
if (errno == EROFS) {
break;
}
if (errno != EBUSY || i > 100) exit(1);
if (umount2(filename, MNT_DETACH | UMOUNT_NOFOLLOW)) exit(1);
}
}
closedir(dp);
for (int i = 0;; i++) {
if (rmdir(dir) == 0) break;
if (i < 100) {
if (errno == EPERM) {
int fd = open(dir, O_RDONLY);
if (fd != -1) {
long flags = 0;
if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0) {
}
close(fd);
continue;
}
}
if (errno == EROFS) {
break;
}
if (errno == EBUSY) {
if (umount2(dir, MNT_DETACH | UMOUNT_NOFOLLOW)) exit(1);
continue;
}
if (errno == ENOTEMPTY) {
if (iter < 100) {
iter++;
goto retry;
}
}
}
exit(1);
}
}

static void kill_and_wait(int pid, int* status) {
kill(-pid, SIGKILL);
kill(pid, SIGKILL);
for (int i = 0; i < 100; i++) {
if (waitpid(-1, status, WNOHANG | __WALL) == pid) return;
usleep(1000);
}
DIR* dir = opendir("/sys/fs/fuse/connections");
if (dir) {
for (;;) {
struct dirent* ent = readdir(dir);
if (!ent) break;
if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
continue;
char abort[300];
snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
ent->d_name);
int fd = open(abort, O_WRONLY);
if (fd == -1) {
continue;
}
if (write(fd, abort, 1) < 0) {
}
close(fd);
}
closedir(dir);
} else {
}
while (waitpid(-1, status, __WALL) != pid) {
}
}

static void setup_test() {
prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
setpgrp();
write_file("/proc/self/oom_score_adj", "1000");
flush_tun();
if (symlink("/dev/binderfs", "./binderfs")) {
}
}

static void close_fds() {
for (int fd = 3; fd < MAX_FDS; fd++) close(fd);
}

static void setup_usb() {
if (chmod("/dev/raw-gadget", 0666)) exit(1);
}

static void setup_sysctl() {
char mypid[32];
snprintf(mypid, sizeof(mypid), "%d", getpid());
struct {
const char* name;
const char* data;
} files[] = {
{"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"},
{"/proc/sys/kernel/hung_task_check_interval_secs", "20"},
{"/proc/sys/net/core/bpf_jit_kallsyms", "1"},
{"/proc/sys/net/core/bpf_jit_harden", "0"},
{"/proc/sys/kernel/kptr_restrict", "0"},
{"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"},
{"/proc/sys/fs/mount-max", "100"},
{"/proc/sys/vm/oom_dump_tasks", "0"},
{"/proc/sys/debug/exception-trace", "0"},
{"/proc/sys/kernel/printk", "7 4 1 3"},
{"/proc/sys/kernel/keys/gc_delay", "1"},
{"/proc/sys/vm/oom_kill_allocating_task", "1"},
{"/proc/sys/kernel/ctrl-alt-del", "0"},
{"/proc/sys/kernel/cad_pid", mypid},
};
for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
if (!write_file(files[i].name, files[i].data))
printf("write to %s failed: %s\n", files[i].name, strerror(errno));
}
}

#define SWAP_FILE "./swap-file"
#define SWAP_FILE_SIZE (128 * 1000 * 1000)

static void setup_swap() {
swapoff(SWAP_FILE);
unlink(SWAP_FILE);
int fd = open(SWAP_FILE, O_CREAT | O_WRONLY | O_CLOEXEC, 0600);
if (fd == -1) {
exit(1);
return;
}
fallocate(fd, FALLOC_FL_ZERO_RANGE, 0, SWAP_FILE_SIZE);
close(fd);
char cmdline[64];
sprintf(cmdline, "mkswap %s", SWAP_FILE);
if (runcmdline(cmdline)) {
exit(1);
return;
}
if (swapon(SWAP_FILE, SWAP_FLAG_PREFER) == 1) {
exit(1);
return;
}
}

static void execute_one(void);

#define WAIT_FLAGS __WALL

static void loop(void) {
int iter = 0;
for (;; iter++) {
char cwdbuf[32];
sprintf(cwdbuf, "./%d", iter);
if (mkdir(cwdbuf, 0777)) exit(1);
int pid = fork();
if (pid < 0) exit(1);
if (pid == 0) {
if (chdir(cwdbuf)) exit(1);
setup_test();
execute_one();
close_fds();
exit(0);
}
int status = 0;
uint64_t start = current_time_ms();
for (;;) {
if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid) break;
sleep_ms(1);
if (current_time_ms() - start < 5000) continue;
kill_and_wait(pid, &status);
break;
}
remove_dir(cwdbuf);
}
}

uint64_t r[5] = {0xffffffffffffffff, 0x0, 0x0, 0xffffffffffffffff, 0x0};

void execute_one(void) {
intptr_t res = 0;
NONFAILING(memcpy((void*)0x20000080, "/dev/dri/card#\000", 15));
res = -1;
NONFAILING(res = syz_open_dev(/*dev=*/0x20000080, /*id=*/0xf2, /*flags=*/0));
if (res != -1) r[0] = res;
NONFAILING(*(uint64_t*)0x20000180 = 0);
NONFAILING(*(uint64_t*)0x20000188 = 0x200000c0);
NONFAILING(*(uint64_t*)0x20000190 = 0);
NONFAILING(*(uint64_t*)0x20000198 = 0);
NONFAILING(*(uint32_t*)0x200001a0 = 0);
NONFAILING(*(uint32_t*)0x200001a4 = 1);
NONFAILING(*(uint32_t*)0x200001a8 = 0);
NONFAILING(*(uint32_t*)0x200001ac = 0);
NONFAILING(*(uint32_t*)0x200001b0 = 0);
NONFAILING(*(uint32_t*)0x200001b4 = 0);
NONFAILING(*(uint32_t*)0x200001b8 = 0);
NONFAILING(*(uint32_t*)0x200001bc = 0);
res = syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0xc04064a0,
/*arg=*/0x20000180ul);
if (res != -1) NONFAILING(r[1] = *(uint32_t*)0x200000c0);
NONFAILING(*(uint64_t*)0x200003c0 = 0);
NONFAILING(*(uint32_t*)0x200003c8 = 0);
NONFAILING(*(uint32_t*)0x200003cc = r[1]);
res = syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0xc06864a1,
/*arg=*/0x200003c0ul);
if (res != -1) NONFAILING(r[2] = *(uint32_t*)0x200003d0);
NONFAILING(memcpy((void*)0x20000080, "/dev/dri/card#\000", 15));
res = -1;
NONFAILING(res = syz_open_dev(/*dev=*/0x20000080, /*id=*/0xf2, /*flags=*/0));
if (res != -1) r[3] = res;
NONFAILING(*(uint64_t*)0x20000180 = 0);
NONFAILING(*(uint64_t*)0x20000188 = 0x200000c0);
NONFAILING(*(uint64_t*)0x20000190 = 0);
NONFAILING(*(uint64_t*)0x20000198 = 0);
NONFAILING(*(uint32_t*)0x200001a0 = 0);
NONFAILING(*(uint32_t*)0x200001a4 = 1);
NONFAILING(*(uint32_t*)0x200001a8 = 0);
NONFAILING(*(uint32_t*)0x200001ac = 0);
NONFAILING(*(uint32_t*)0x200001b0 = 0);
NONFAILING(*(uint32_t*)0x200001b4 = 0);
NONFAILING(*(uint32_t*)0x200001b8 = 0);
NONFAILING(*(uint32_t*)0x200001bc = 0);
res = syscall(__NR_ioctl, /*fd=*/r[3], /*cmd=*/0xc04064a0,
/*arg=*/0x20000180ul);
if (res != -1) NONFAILING(r[4] = *(uint32_t*)0x200000c0);
NONFAILING(*(uint32_t*)0x20000000 = r[4]);
NONFAILING(*(uint32_t*)0x20000004 = r[2]);
NONFAILING(*(uint32_t*)0x20000008 = 0);
NONFAILING(*(uint32_t*)0x2000000c = 0);
NONFAILING(*(uint64_t*)0x20000010 = 0x80000003);
syscall(__NR_ioctl, /*fd=*/r[0], /*cmd=*/0xc01864b0, /*arg=*/0x20000000ul);
}
int main(void) {
syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
/*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul, /*prot=*/7ul,
/*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
/*flags=*/0x32ul, /*fd=*/-1, /*offset=*/0ul);
setup_sysctl();
setup_usb();
setup_swap();
install_segv_handler();
use_temporary_dir();
do_sandbox_none();
return 0;
}

and see also https://gist.github.com/xrivendell7/aceeaacd33afccf6f453ba8e2d3bd403