kernel_optimize_test/kernel
Eric W. Biederman 70f1b0d34b signal/usb: Replace kill_pid_info_as_cred with kill_pid_usb_asyncio
The usb support for asyncio encoded one of it's values in the wrong
field.  It should have used si_value but instead used si_addr which is
not present in the _rt union member of struct siginfo.

The practical result of this is that on a 64bit big endian kernel
when delivering a signal to a 32bit process the si_addr field
is set to NULL, instead of the expected pointer value.

This issue can not be fixed in copy_siginfo_to_user32 as the usb
usage of the the _sigfault (aka si_addr) member of the siginfo
union when SI_ASYNCIO is set is incompatible with the POSIX and
glibc usage of the _rt member of the siginfo union.

Therefore replace kill_pid_info_as_cred with kill_pid_usb_asyncio a
dedicated function for this one specific case.  There are no other
users of kill_pid_info_as_cred so this specialization should have no
impact on the amount of code in the kernel.  Have kill_pid_usb_asyncio
take instead of a siginfo_t which is difficult and error prone, 3
arguments, a signal number, an errno value, and an address enconded as
a sigval_t.  The encoding of the address as a sigval_t allows the
code that reads the userspace request for a signal to handle this
compat issue along with all of the other compat issues.

Add BUILD_BUG_ONs in kernel/signal.c to ensure that we can now place
the pointer value at the in si_pid (instead of si_addr).  That is the
code now verifies that si_pid and si_addr always occur at the same
location.  Further the code veries that for native structures a value
placed in si_pid and spilling into si_uid will appear in userspace in
si_addr (on a byte by byte copy of siginfo or a field by field copy of
siginfo).  The code also verifies that for a 64bit kernel and a 32bit
userspace the 32bit pointer will fit in si_pid.

I have used the usbsig.c program below written by Alan Stern and
slightly tweaked by me to run on a big endian machine to verify the
issue exists (on sparc64) and to confirm the patch below fixes the issue.

 /* usbsig.c -- test USB async signal delivery */

 #define _GNU_SOURCE
 #include <stdio.h>
 #include <fcntl.h>
 #include <signal.h>
 #include <string.h>
 #include <sys/ioctl.h>
 #include <unistd.h>
 #include <endian.h>
 #include <linux/usb/ch9.h>
 #include <linux/usbdevice_fs.h>

 static struct usbdevfs_urb urb;
 static struct usbdevfs_disconnectsignal ds;
 static volatile sig_atomic_t done = 0;

 void urb_handler(int sig, siginfo_t *info , void *ucontext)
 {
 	printf("Got signal %d, signo %d errno %d code %d addr: %p urb: %p\n",
 	       sig, info->si_signo, info->si_errno, info->si_code,
 	       info->si_addr, &urb);

 	printf("%s\n", (info->si_addr == &urb) ? "Good" : "Bad");
 }

 void ds_handler(int sig, siginfo_t *info , void *ucontext)
 {
 	printf("Got signal %d, signo %d errno %d code %d addr: %p ds: %p\n",
 	       sig, info->si_signo, info->si_errno, info->si_code,
 	       info->si_addr, &ds);

 	printf("%s\n", (info->si_addr == &ds) ? "Good" : "Bad");
 	done = 1;
 }

 int main(int argc, char **argv)
 {
 	char *devfilename;
 	int fd;
 	int rc;
 	struct sigaction act;
 	struct usb_ctrlrequest *req;
 	void *ptr;
 	char buf[80];

 	if (argc != 2) {
 		fprintf(stderr, "Usage: usbsig device-file-name\n");
 		return 1;
 	}

 	devfilename = argv[1];
 	fd = open(devfilename, O_RDWR);
 	if (fd == -1) {
 		perror("Error opening device file");
 		return 1;
 	}

 	act.sa_sigaction = urb_handler;
 	sigemptyset(&act.sa_mask);
 	act.sa_flags = SA_SIGINFO;

 	rc = sigaction(SIGUSR1, &act, NULL);
 	if (rc == -1) {
 		perror("Error in sigaction");
 		return 1;
 	}

 	act.sa_sigaction = ds_handler;
 	sigemptyset(&act.sa_mask);
 	act.sa_flags = SA_SIGINFO;

 	rc = sigaction(SIGUSR2, &act, NULL);
 	if (rc == -1) {
 		perror("Error in sigaction");
 		return 1;
 	}

 	memset(&urb, 0, sizeof(urb));
 	urb.type = USBDEVFS_URB_TYPE_CONTROL;
 	urb.endpoint = USB_DIR_IN | 0;
 	urb.buffer = buf;
 	urb.buffer_length = sizeof(buf);
 	urb.signr = SIGUSR1;

 	req = (struct usb_ctrlrequest *) buf;
 	req->bRequestType = USB_DIR_IN | USB_TYPE_STANDARD | USB_RECIP_DEVICE;
 	req->bRequest = USB_REQ_GET_DESCRIPTOR;
 	req->wValue = htole16(USB_DT_DEVICE << 8);
 	req->wIndex = htole16(0);
 	req->wLength = htole16(sizeof(buf) - sizeof(*req));

 	rc = ioctl(fd, USBDEVFS_SUBMITURB, &urb);
 	if (rc == -1) {
 		perror("Error in SUBMITURB ioctl");
 		return 1;
 	}

 	rc = ioctl(fd, USBDEVFS_REAPURB, &ptr);
 	if (rc == -1) {
 		perror("Error in REAPURB ioctl");
 		return 1;
 	}

 	memset(&ds, 0, sizeof(ds));
 	ds.signr = SIGUSR2;
 	ds.context = &ds;
 	rc = ioctl(fd, USBDEVFS_DISCSIGNAL, &ds);
 	if (rc == -1) {
 		perror("Error in DISCSIGNAL ioctl");
 		return 1;
 	}

 	printf("Waiting for usb disconnect\n");
 	while (!done) {
 		sleep(1);
 	}

 	close(fd);
 	return 0;
 }

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Oliver Neukum <oneukum@suse.com>
Fixes: v2.3.39
Cc: stable@vger.kernel.org
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2019-05-22 16:53:48 -05:00
..
bpf bpf: fix undefined behavior in narrow load handling 2019-05-13 02:05:50 +02:00
cgroup kernel/sched/psi.c: expose pressure metrics on root cgroup 2019-05-14 19:52:48 -07:00
configs
debug kdb: Fix bound check compiler warning 2019-05-14 13:44:24 +01:00
dma DMA mapping updates for 5.2 2019-05-09 08:40:55 -07:00
events mm/mmu_notifier: use correct mmu_notifier events for each invalidation 2019-05-14 09:47:49 -07:00
gcov gcov: clang support 2019-05-14 19:52:51 -07:00
irq Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-05-19 10:58:45 -07:00
livepatch The major changes in this tracing update includes: 2019-05-15 16:05:47 -07:00
locking locking/rwsem: Prevent decrement of reader count before increment 2019-05-07 08:46:46 +02:00
power Power management updates for 5.2-rc1 2019-05-06 19:40:31 -07:00
printk panic: add an option to replay all the printk message in buffer 2019-05-18 15:52:26 -07:00
rcu The major changes in this tracing update includes: 2019-05-15 16:05:47 -07:00
sched kernel/sched/psi.c: expose pressure metrics on root cgroup 2019-05-14 19:52:48 -07:00
time Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-05-16 11:00:20 -07:00
trace The major changes in this tracing update includes: 2019-05-15 16:05:47 -07:00
.gitignore Provide in-kernel headers to make extending kernel easier 2019-04-29 16:48:03 +02:00
acct.c acct_on(): don't mess with freeze protection 2019-04-04 21:04:13 -04:00
async.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
audit_fsnotify.c audit_compare_dname_path(): switch to const struct qstr * 2019-04-28 20:33:43 -04:00
audit_tree.c fsnotify: switch send_to_group() and ->handle_event to const struct qstr * 2019-04-26 13:51:03 -04:00
audit_watch.c audit_compare_dname_path(): switch to const struct qstr * 2019-04-28 20:33:43 -04:00
audit.c audit: connect LOGIN record to its syscall record 2019-03-20 20:57:48 -04:00
audit.h audit_compare_dname_path(): switch to const struct qstr * 2019-04-28 20:33:43 -04:00
auditfilter.c Merge branch 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-05-07 20:03:32 -07:00
auditsc.c Merge branch 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-05-07 20:03:32 -07:00
backtracetest.c backtrace-test: Simplify stack trace handling 2019-04-29 12:37:47 +02:00
bounds.c
capability.c
compat.c kernel/compat.c: mark expected switch fall-throughs 2019-05-15 08:16:14 -07:00
configs.c kernel/configs: use .incbin directive to embed config_data.gz 2019-03-07 18:32:02 -08:00
context_tracking.c
cpu_pm.c
cpu.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2019-05-06 14:50:46 -07:00
crash_core.c kexec: export PG_offline to VMCOREINFO 2019-03-05 21:07:14 -08:00
crash_dump.c
cred.c
delayacct.c
dma.c
elfcore.c
exec_domain.c
exit.c mm: change mm_update_next_owner() to update mm->owner with WRITE_ONCE 2019-05-14 19:52:47 -07:00
extable.c
fail_function.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
fork.c kernel/latencytop.c: rename clear_all_latency_tracing to clear_tsk_latency_tracing 2019-05-14 19:52:49 -07:00
freezer.c
futex.c mm/gup: change GUP fast to use flags rather than a write 'bool' 2019-05-14 09:47:46 -07:00
gen_ikh_data.sh Provide in-kernel headers to make extending kernel easier 2019-04-29 16:48:03 +02:00
groups.c
hung_task.c kernel/hung_task.c: Use continuously blocked time when reporting. 2019-03-07 18:31:59 -08:00
iomem.c mm/resource: Use resource_overlaps() to simplify region_intersects() 2019-04-19 12:59:36 +02:00
irq_work.c irq_work: Do not raise an IPI when queueing work on the local CPU 2019-04-18 14:07:52 +02:00
jump_label.c locking/static_key: Don't take sleeping locks in __static_key_slow_dec_deferred() 2019-04-29 08:29:21 +02:00
kallsyms.c
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks Remove Mysterious Macro Intended to Obscure Weird Behaviours (mmiowb()) 2019-05-06 16:57:52 -07:00
Kconfig.preempt
kcov.c kcov: convert kcov.refcount to refcount_t 2019-03-07 18:32:02 -08:00
kexec_core.c power/suspend: Add function to disable secondaries for suspend 2019-05-03 19:42:41 +02:00
kexec_file.c mm: memblock: make keeping memblock memory opt-in rather than opt-out 2019-05-14 09:47:50 -07:00
kexec_internal.h
kexec.c
kheaders.c Provide in-kernel headers to make extending kernel easier 2019-04-29 16:48:03 +02:00
kmod.c
kprobes.c kprobes: Fix error check when reusing optimized probes 2019-04-16 09:38:16 +02:00
ksysfs.c
kthread.c include/: refactor headers to allow kthread.h inclusion in psi_types.h 2019-05-14 19:52:48 -07:00
latencytop.c kernel/latencytop.c: rename clear_all_latency_tracing to clear_tsk_latency_tracing 2019-05-14 19:52:49 -07:00
Makefile kernel/Makefile: don't assume that kernel/gen_ikh_data.sh is executable 2019-05-14 19:52:47 -07:00
memremap.c kernel/memremap.c: remove the unused device_private_entry_fault() export 2019-05-14 09:47:51 -07:00
module_signing.c
module-internal.h kallsyms: store type information in its own array 2019-03-28 15:00:37 +01:00
module.c Modules updates for v5.2 2019-05-14 10:55:54 -07:00
notifier.c kernel/notifier.c: double register detection 2019-05-14 19:52:49 -07:00
nsproxy.c
padata.c padata: Replace padata_attr_type default_attrs field with groups 2019-04-25 22:06:11 +02:00
panic.c panic: add an option to replay all the printk message in buffer 2019-05-18 15:52:26 -07:00
params.c
pid_namespace.c
pid.c kernel/pid.c: remove unneeded hash header file 2019-05-14 19:52:51 -07:00
profile.c
ptrace.c ptrace: take into account saved_sigmask in PTRACE{GET,SET}SIGMASK 2019-03-29 10:01:37 -07:00
range.c
reboot.c panic/reboot: allow specifying reboot_mode for panic only 2019-05-14 19:52:51 -07:00
relay.c Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2019-03-12 13:27:20 -07:00
resource.c mm/resource: Use resource_overlaps() to simplify region_intersects() 2019-04-19 12:59:36 +02:00
rseq.c rseq: Remove superfluous rseq_len from task_struct 2019-04-19 12:39:32 +02:00
seccomp.c audit/stable-5.2 PR 20190507 2019-05-07 19:06:04 -07:00
signal.c signal/usb: Replace kill_pid_info_as_cred with kill_pid_usb_asyncio 2019-05-22 16:53:48 -05:00
smp.c
smpboot.c
smpboot.h
softirq.c softirq: Remove tasklet_hrtimer 2019-03-22 14:36:02 +01:00
stackleak.c
stacktrace.c stacktrace: Provide common infrastructure 2019-04-29 12:37:57 +02:00
stop_machine.c treewide: Switch printk users from %pf and %pF to %ps and %pS, respectively 2019-04-09 14:19:06 +02:00
sys_ni.c signal: support CLONE_PIDFD with pidfd_send_signal 2019-05-07 14:31:03 +02:00
sys.c kernel/sys.c: prctl: fix false positive in validate_prctl_map() 2019-05-14 09:47:44 -07:00
sysctl_binary.c
sysctl.c kernel/sysctl.c: fix proc_do_large_bitmap for large input buffers 2019-05-14 19:52:51 -07:00
task_work.c
taskstats.c genetlink: optionally validate strictly/dumps 2019-04-27 17:07:22 -04:00
test_kprobes.c
torture.c torture: Don't try to offline the last CPU 2019-03-26 14:42:53 -07:00
tracepoint.c
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c
up.c
user_namespace.c
user-return-notifier.c
user.c kernel/user.c: clean up some leftover code 2019-05-14 19:52:49 -07:00
utsname_sysctl.c
utsname.c
watchdog_hld.c kernel/watchdog_hld.c: hard lockup message should end with a newline 2019-04-19 09:46:05 -07:00
watchdog.c watchdog: Fix typo in comment 2019-04-18 14:05:51 +02:00
workqueue_internal.h sched/core, workqueues: Distangle worker accounting from rq lock 2019-04-16 16:55:15 +02:00
workqueue.c Merge branch 'for-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq 2019-05-09 13:48:52 -07:00