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-rw-r--r--kernel/signal.c354
1 files changed, 333 insertions, 21 deletions
diff --git a/kernel/signal.c b/kernel/signal.c
index 9558664bd9ec..c6e4c83dc090 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -40,6 +40,7 @@
#include <linux/cn_proc.h>
#include <linux/compiler.h>
#include <linux/posix-timers.h>
+#include <linux/livepatch.h>
#define CREATE_TRACE_POINTS
#include <trace/events/signal.h>
@@ -165,7 +166,8 @@ void recalc_sigpending_and_wake(struct task_struct *t)
void recalc_sigpending(void)
{
- if (!recalc_sigpending_tsk(current) && !freezing(current))
+ if (!recalc_sigpending_tsk(current) && !freezing(current) &&
+ !klp_patch_pending(current))
clear_thread_flag(TIF_SIGPENDING);
}
@@ -549,6 +551,7 @@ still_pending:
* a fast-pathed signal or we must have been
* out of queue space. So zero out the info.
*/
+ clear_siginfo(info);
info->si_signo = sig;
info->si_errno = 0;
info->si_code = SI_USER;
@@ -642,6 +645,9 @@ int dequeue_signal(struct task_struct *tsk, sigset_t *mask, siginfo_t *info)
spin_unlock(&tsk->sighand->siglock);
posixtimer_rearm(info);
spin_lock(&tsk->sighand->siglock);
+
+ /* Don't expose the si_sys_private value to userspace */
+ info->si_sys_private = 0;
}
#endif
return signr;
@@ -1043,6 +1049,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
list_add_tail(&q->list, &pending->list);
switch ((unsigned long) info) {
case (unsigned long) SEND_SIG_NOINFO:
+ clear_siginfo(&q->info);
q->info.si_signo = sig;
q->info.si_errno = 0;
q->info.si_code = SI_USER;
@@ -1051,6 +1058,7 @@ static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
q->info.si_uid = from_kuid_munged(current_user_ns(), current_uid());
break;
case (unsigned long) SEND_SIG_PRIV:
+ clear_siginfo(&q->info);
q->info.si_signo = sig;
q->info.si_errno = 0;
q->info.si_code = SI_KERNEL;
@@ -1485,6 +1493,129 @@ force_sigsegv(int sig, struct task_struct *p)
return 0;
}
+int force_sig_fault(int sig, int code, void __user *addr
+ ___ARCH_SI_TRAPNO(int trapno)
+ ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
+ , struct task_struct *t)
+{
+ struct siginfo info;
+
+ clear_siginfo(&info);
+ info.si_signo = sig;
+ info.si_errno = 0;
+ info.si_code = code;
+ info.si_addr = addr;
+#ifdef __ARCH_SI_TRAPNO
+ info.si_trapno = trapno;
+#endif
+#ifdef __ia64__
+ info.si_imm = imm;
+ info.si_flags = flags;
+ info.si_isr = isr;
+#endif
+ return force_sig_info(info.si_signo, &info, t);
+}
+
+int send_sig_fault(int sig, int code, void __user *addr
+ ___ARCH_SI_TRAPNO(int trapno)
+ ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)
+ , struct task_struct *t)
+{
+ struct siginfo info;
+
+ clear_siginfo(&info);
+ info.si_signo = sig;
+ info.si_errno = 0;
+ info.si_code = code;
+ info.si_addr = addr;
+#ifdef __ARCH_SI_TRAPNO
+ info.si_trapno = trapno;
+#endif
+#ifdef __ia64__
+ info.si_imm = imm;
+ info.si_flags = flags;
+ info.si_isr = isr;
+#endif
+ return send_sig_info(info.si_signo, &info, t);
+}
+
+#if defined(BUS_MCEERR_AO) && defined(BUS_MCEERR_AR)
+int force_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t)
+{
+ struct siginfo info;
+
+ WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR));
+ clear_siginfo(&info);
+ info.si_signo = SIGBUS;
+ info.si_errno = 0;
+ info.si_code = code;
+ info.si_addr = addr;
+ info.si_addr_lsb = lsb;
+ return force_sig_info(info.si_signo, &info, t);
+}
+
+int send_sig_mceerr(int code, void __user *addr, short lsb, struct task_struct *t)
+{
+ struct siginfo info;
+
+ WARN_ON((code != BUS_MCEERR_AO) && (code != BUS_MCEERR_AR));
+ clear_siginfo(&info);
+ info.si_signo = SIGBUS;
+ info.si_errno = 0;
+ info.si_code = code;
+ info.si_addr = addr;
+ info.si_addr_lsb = lsb;
+ return send_sig_info(info.si_signo, &info, t);
+}
+EXPORT_SYMBOL(send_sig_mceerr);
+#endif
+
+#ifdef SEGV_BNDERR
+int force_sig_bnderr(void __user *addr, void __user *lower, void __user *upper)
+{
+ struct siginfo info;
+
+ clear_siginfo(&info);
+ info.si_signo = SIGSEGV;
+ info.si_errno = 0;
+ info.si_code = SEGV_BNDERR;
+ info.si_addr = addr;
+ info.si_lower = lower;
+ info.si_upper = upper;
+ return force_sig_info(info.si_signo, &info, current);
+}
+#endif
+
+#ifdef SEGV_PKUERR
+int force_sig_pkuerr(void __user *addr, u32 pkey)
+{
+ struct siginfo info;
+
+ clear_siginfo(&info);
+ info.si_signo = SIGSEGV;
+ info.si_errno = 0;
+ info.si_code = SEGV_PKUERR;
+ info.si_addr = addr;
+ info.si_pkey = pkey;
+ return force_sig_info(info.si_signo, &info, current);
+}
+#endif
+
+/* For the crazy architectures that include trap information in
+ * the errno field, instead of an actual errno value.
+ */
+int force_sig_ptrace_errno_trap(int errno, void __user *addr)
+{
+ struct siginfo info;
+
+ clear_siginfo(&info);
+ info.si_signo = SIGTRAP;
+ info.si_errno = errno;
+ info.si_code = TRAP_HWBKPT;
+ info.si_addr = addr;
+ return force_sig_info(info.si_signo, &info, current);
+}
+
int kill_pgrp(struct pid *pid, int sig, int priv)
{
int ret;
@@ -1623,6 +1754,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
sig = SIGCHLD;
}
+ clear_siginfo(&info);
info.si_signo = sig;
info.si_errno = 0;
/*
@@ -1717,6 +1849,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
parent = tsk->real_parent;
}
+ clear_siginfo(&info);
info.si_signo = SIGCHLD;
info.si_errno = 0;
/*
@@ -1929,7 +2062,7 @@ static void ptrace_do_notify(int signr, int exit_code, int why)
{
siginfo_t info;
- memset(&info, 0, sizeof info);
+ clear_siginfo(&info);
info.si_signo = signr;
info.si_code = exit_code;
info.si_pid = task_pid_vnr(current);
@@ -2136,6 +2269,7 @@ static int ptrace_signal(int signr, siginfo_t *info)
* have updated *info via PTRACE_SETSIGINFO.
*/
if (signr != info->si_signo) {
+ clear_siginfo(info);
info->si_signo = signr;
info->si_errno = 0;
info->si_code = SI_USER;
@@ -2688,9 +2822,7 @@ enum siginfo_layout siginfo_layout(int sig, int si_code)
#endif
[SIGCHLD] = { NSIGCHLD, SIL_CHLD },
[SIGPOLL] = { NSIGPOLL, SIL_POLL },
-#ifdef __ARCH_SIGSYS
[SIGSYS] = { NSIGSYS, SIL_SYS },
-#endif
};
if ((sig < ARRAY_SIZE(filter)) && (si_code <= filter[sig].limit))
layout = filter[sig].layout;
@@ -2712,12 +2844,14 @@ enum siginfo_layout siginfo_layout(int sig, int si_code)
if ((sig == SIGFPE) && (si_code == FPE_FIXME))
layout = SIL_FAULT;
#endif
+#ifdef BUS_FIXME
+ if ((sig == SIGBUS) && (si_code == BUS_FIXME))
+ layout = SIL_FAULT;
+#endif
}
return layout;
}
-#ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER
-
int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from)
{
int err;
@@ -2756,13 +2890,21 @@ int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from)
#ifdef __ARCH_SI_TRAPNO
err |= __put_user(from->si_trapno, &to->si_trapno);
#endif
-#ifdef BUS_MCEERR_AO
+#ifdef __ia64__
+ err |= __put_user(from->si_imm, &to->si_imm);
+ err |= __put_user(from->si_flags, &to->si_flags);
+ err |= __put_user(from->si_isr, &to->si_isr);
+#endif
/*
* Other callers might not initialize the si_lsb field,
* so check explicitly for the right codes here.
*/
- if (from->si_signo == SIGBUS &&
- (from->si_code == BUS_MCEERR_AR || from->si_code == BUS_MCEERR_AO))
+#ifdef BUS_MCEERR_AR
+ if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AR)
+ err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
+#endif
+#ifdef BUS_MCEERR_AO
+ if (from->si_signo == SIGBUS && from->si_code == BUS_MCEERR_AO)
err |= __put_user(from->si_addr_lsb, &to->si_addr_lsb);
#endif
#ifdef SEGV_BNDERR
@@ -2788,18 +2930,185 @@ int copy_siginfo_to_user(siginfo_t __user *to, const siginfo_t *from)
err |= __put_user(from->si_uid, &to->si_uid);
err |= __put_user(from->si_ptr, &to->si_ptr);
break;
-#ifdef __ARCH_SIGSYS
case SIL_SYS:
err |= __put_user(from->si_call_addr, &to->si_call_addr);
err |= __put_user(from->si_syscall, &to->si_syscall);
err |= __put_user(from->si_arch, &to->si_arch);
break;
-#endif
}
return err;
}
+#ifdef CONFIG_COMPAT
+int copy_siginfo_to_user32(struct compat_siginfo __user *to,
+ const struct siginfo *from)
+#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION)
+{
+ return __copy_siginfo_to_user32(to, from, in_x32_syscall());
+}
+int __copy_siginfo_to_user32(struct compat_siginfo __user *to,
+ const struct siginfo *from, bool x32_ABI)
+#endif
+{
+ struct compat_siginfo new;
+ memset(&new, 0, sizeof(new));
+
+ new.si_signo = from->si_signo;
+ new.si_errno = from->si_errno;
+ new.si_code = from->si_code;
+ switch(siginfo_layout(from->si_signo, from->si_code)) {
+ case SIL_KILL:
+ new.si_pid = from->si_pid;
+ new.si_uid = from->si_uid;
+ break;
+ case SIL_TIMER:
+ new.si_tid = from->si_tid;
+ new.si_overrun = from->si_overrun;
+ new.si_int = from->si_int;
+ break;
+ case SIL_POLL:
+ new.si_band = from->si_band;
+ new.si_fd = from->si_fd;
+ break;
+ case SIL_FAULT:
+ new.si_addr = ptr_to_compat(from->si_addr);
+#ifdef __ARCH_SI_TRAPNO
+ new.si_trapno = from->si_trapno;
+#endif
+#ifdef BUS_MCEERR_AR
+ if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AR))
+ new.si_addr_lsb = from->si_addr_lsb;
+#endif
+#ifdef BUS_MCEERR_AO
+ if ((from->si_signo == SIGBUS) && (from->si_code == BUS_MCEERR_AO))
+ new.si_addr_lsb = from->si_addr_lsb;
+#endif
+#ifdef SEGV_BNDERR
+ if ((from->si_signo == SIGSEGV) &&
+ (from->si_code == SEGV_BNDERR)) {
+ new.si_lower = ptr_to_compat(from->si_lower);
+ new.si_upper = ptr_to_compat(from->si_upper);
+ }
+#endif
+#ifdef SEGV_PKUERR
+ if ((from->si_signo == SIGSEGV) &&
+ (from->si_code == SEGV_PKUERR))
+ new.si_pkey = from->si_pkey;
+#endif
+
+ break;
+ case SIL_CHLD:
+ new.si_pid = from->si_pid;
+ new.si_uid = from->si_uid;
+ new.si_status = from->si_status;
+#ifdef CONFIG_X86_X32_ABI
+ if (x32_ABI) {
+ new._sifields._sigchld_x32._utime = from->si_utime;
+ new._sifields._sigchld_x32._stime = from->si_stime;
+ } else
+#endif
+ {
+ new.si_utime = from->si_utime;
+ new.si_stime = from->si_stime;
+ }
+ break;
+ case SIL_RT:
+ new.si_pid = from->si_pid;
+ new.si_uid = from->si_uid;
+ new.si_int = from->si_int;
+ break;
+ case SIL_SYS:
+ new.si_call_addr = ptr_to_compat(from->si_call_addr);
+ new.si_syscall = from->si_syscall;
+ new.si_arch = from->si_arch;
+ break;
+ }
+
+ if (copy_to_user(to, &new, sizeof(struct compat_siginfo)))
+ return -EFAULT;
+
+ return 0;
+}
+
+int copy_siginfo_from_user32(struct siginfo *to,
+ const struct compat_siginfo __user *ufrom)
+{
+ struct compat_siginfo from;
+
+ if (copy_from_user(&from, ufrom, sizeof(struct compat_siginfo)))
+ return -EFAULT;
+
+ clear_siginfo(to);
+ to->si_signo = from.si_signo;
+ to->si_errno = from.si_errno;
+ to->si_code = from.si_code;
+ switch(siginfo_layout(from.si_signo, from.si_code)) {
+ case SIL_KILL:
+ to->si_pid = from.si_pid;
+ to->si_uid = from.si_uid;
+ break;
+ case SIL_TIMER:
+ to->si_tid = from.si_tid;
+ to->si_overrun = from.si_overrun;
+ to->si_int = from.si_int;
+ break;
+ case SIL_POLL:
+ to->si_band = from.si_band;
+ to->si_fd = from.si_fd;
+ break;
+ case SIL_FAULT:
+ to->si_addr = compat_ptr(from.si_addr);
+#ifdef __ARCH_SI_TRAPNO
+ to->si_trapno = from.si_trapno;
+#endif
+#ifdef BUS_MCEERR_AR
+ if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AR))
+ to->si_addr_lsb = from.si_addr_lsb;
+#endif
+#ifdef BUS_MCEER_AO
+ if ((from.si_signo == SIGBUS) && (from.si_code == BUS_MCEERR_AO))
+ to->si_addr_lsb = from.si_addr_lsb;
+#endif
+#ifdef SEGV_BNDERR
+ if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_BNDERR)) {
+ to->si_lower = compat_ptr(from.si_lower);
+ to->si_upper = compat_ptr(from.si_upper);
+ }
+#endif
+#ifdef SEGV_PKUERR
+ if ((from.si_signo == SIGSEGV) && (from.si_code == SEGV_PKUERR))
+ to->si_pkey = from.si_pkey;
+#endif
+ break;
+ case SIL_CHLD:
+ to->si_pid = from.si_pid;
+ to->si_uid = from.si_uid;
+ to->si_status = from.si_status;
+#ifdef CONFIG_X86_X32_ABI
+ if (in_x32_syscall()) {
+ to->si_utime = from._sifields._sigchld_x32._utime;
+ to->si_stime = from._sifields._sigchld_x32._stime;
+ } else
#endif
+ {
+ to->si_utime = from.si_utime;
+ to->si_stime = from.si_stime;
+ }
+ break;
+ case SIL_RT:
+ to->si_pid = from.si_pid;
+ to->si_uid = from.si_uid;
+ to->si_int = from.si_int;
+ break;
+ case SIL_SYS:
+ to->si_call_addr = compat_ptr(from.si_call_addr);
+ to->si_syscall = from.si_syscall;
+ to->si_arch = from.si_arch;
+ break;
+ }
+ return 0;
+}
+#endif /* CONFIG_COMPAT */
/**
* do_sigtimedwait - wait for queued signals specified in @which
@@ -2937,6 +3246,7 @@ SYSCALL_DEFINE2(kill, pid_t, pid, int, sig)
{
struct siginfo info;
+ clear_siginfo(&info);
info.si_signo = sig;
info.si_errno = 0;
info.si_code = SI_USER;
@@ -2978,8 +3288,9 @@ do_send_specific(pid_t tgid, pid_t pid, int sig, struct siginfo *info)
static int do_tkill(pid_t tgid, pid_t pid, int sig)
{
- struct siginfo info = {};
+ struct siginfo info;
+ clear_siginfo(&info);
info.si_signo = sig;
info.si_errno = 0;
info.si_code = SI_TKILL;
@@ -3060,7 +3371,7 @@ COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo,
int, sig,
struct compat_siginfo __user *, uinfo)
{
- siginfo_t info = {};
+ siginfo_t info;
int ret = copy_siginfo_from_user32(&info, uinfo);
if (unlikely(ret))
return ret;
@@ -3104,7 +3415,7 @@ COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo,
int, sig,
struct compat_siginfo __user *, uinfo)
{
- siginfo_t info = {};
+ siginfo_t info;
if (copy_siginfo_from_user32(&info, uinfo))
return -EFAULT;
@@ -3677,6 +3988,7 @@ void __init signals_init(void)
/* If this check fails, the __ARCH_SI_PREAMBLE_SIZE value is wrong! */
BUILD_BUG_ON(__ARCH_SI_PREAMBLE_SIZE
!= offsetof(struct siginfo, _sifields._pad));
+ BUILD_BUG_ON(sizeof(struct siginfo) != SI_MAX_SIZE);
sigqueue_cachep = KMEM_CACHE(sigqueue, SLAB_PANIC);
}
@@ -3684,26 +3996,25 @@ void __init signals_init(void)
#ifdef CONFIG_KGDB_KDB
#include <linux/kdb.h>
/*
- * kdb_send_sig_info - Allows kdb to send signals without exposing
+ * kdb_send_sig - Allows kdb to send signals without exposing
* signal internals. This function checks if the required locks are
* available before calling the main signal code, to avoid kdb
* deadlocks.
*/
-void
-kdb_send_sig_info(struct task_struct *t, struct siginfo *info)
+void kdb_send_sig(struct task_struct *t, int sig)
{
static struct task_struct *kdb_prev_t;
- int sig, new_t;
+ int new_t, ret;
if (!spin_trylock(&t->sighand->siglock)) {
kdb_printf("Can't do kill command now.\n"
"The sigmask lock is held somewhere else in "
"kernel, try again later\n");
return;
}
- spin_unlock(&t->sighand->siglock);
new_t = kdb_prev_t != t;
kdb_prev_t = t;
if (t->state != TASK_RUNNING && new_t) {
+ spin_unlock(&t->sighand->siglock);
kdb_printf("Process is not RUNNING, sending a signal from "
"kdb risks deadlock\n"
"on the run queue locks. "
@@ -3712,8 +4023,9 @@ kdb_send_sig_info(struct task_struct *t, struct siginfo *info)
"the deadlock.\n");
return;
}
- sig = info->si_signo;
- if (send_sig_info(sig, info, t))
+ ret = send_signal(sig, SEND_SIG_PRIV, t, false);
+ spin_unlock(&t->sighand->siglock);
+ if (ret)
kdb_printf("Fail to deliver Signal %d to process %d.\n",
sig, t->pid);
else