3.10.102-> 3.10.103

6 files changed, 71 insertions, 15 deletions

diff --git a/kernel/module.c b/kernel/module.c
index d50d899b0..36df6184e 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2475,13 +2475,18 @@ static inline void kmemleak_load_module(const struct module *mod,
 #endif
 
 #ifdef CONFIG_MODULE_SIG
-static int module_sig_check(struct load_info *info)
+static int module_sig_check(struct load_info *info, int flags)
 {
 	int err = -ENOKEY;
 	const unsigned long markerlen = sizeof(MODULE_SIG_STRING) - 1;
 	const void *mod = info->hdr;
 
-	if (info->len > markerlen &&
+	/*
+	 * Require flags == 0, as a module with version information
+	 * removed is no longer the module that was signed
+	 */
+	if (flags == 0 &&
+	    info->len > markerlen &&
 	    memcmp(mod + info->len - markerlen, MODULE_SIG_STRING, markerlen) == 0) {
 		/* We truncate the module to discard the signature */
 		info->len -= markerlen;
@@ -2503,7 +2508,7 @@ static int module_sig_check(struct load_info *info)
 	return err;
 }
 #else /* !CONFIG_MODULE_SIG */
-static int module_sig_check(struct load_info *info)
+static int module_sig_check(struct load_info *info, int flags)
 {
 	return 0;
 }
@@ -3228,7 +3233,7 @@ static int load_module(struct load_info *info, const char __user *uargs,
 	struct module *mod;
 	long err;
 
-	err = module_sig_check(info);
+	err = module_sig_check(info, flags);
 	if (err)
 		goto free_copy;
 
diff --git a/kernel/panic.c b/kernel/panic.c
index 1050697a7..55f2f3129 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -22,6 +22,7 @@
 #include <linux/sysrq.h>
 #include <linux/init.h>
 #include <linux/nmi.h>
+#include <linux/console.h>
 
 #define PANIC_TIMER_STEP 100
 #define PANIC_BLINK_SPD 18
@@ -134,6 +135,8 @@ void panic(const char *fmt, ...)
 
 	bust_spinlocks(0);
 
+	console_flush_on_panic();
+
 	if (!panic_blink)
 		panic_blink = no_blink;
 
diff --git a/kernel/printk.c b/kernel/printk.c
index b30c61814..95cfcfd30 100644
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -2161,7 +2161,7 @@ void console_unlock(void)
 	static u64 seen_seq;
 	unsigned long flags;
 	bool wake_klogd = false;
-	bool retry;
+	bool do_cond_resched, retry;
 #ifdef LOG_TOO_MUCH_WARNING
     unsigned long total_log_size = 0;
     unsigned long long t1 = 0, t2 = 0;
@@ -2174,6 +2174,18 @@ void console_unlock(void)
 		return;
 	}
 
+	/*
+	 * Console drivers are called under logbuf_lock, so
+	 * @console_may_schedule should be cleared before; however, we may
+	 * end up dumping a lot of lines, for example, if called from
+	 * console registration path, and should invoke cond_resched()
+	 * between lines if allowable.  Not doing so can cause a very long
+	 * scheduling stall on a slow console leading to RCU stall and
+	 * softlockup warnings which exacerbate the issue with more
+	 * messages practically incapacitating the system.
+	 */
+	do_cond_resched = console_may_schedule;
+
 	console_may_schedule = 0;
 
 	/* flush buffered message fragment immediately to console */
@@ -2269,6 +2281,8 @@ skip:
         call_console_drivers(level, text, len);
 #endif
 		local_irq_restore(flags);
+		if (do_cond_resched)
+			cond_resched();
 	}
 	console_locked = 0;
 	mutex_release(&console_lock_dep_map, 1, _RET_IP_);
@@ -2337,6 +2351,25 @@ void console_unblank(void)
 	console_unlock();
 }
 
+/**
+ * console_flush_on_panic - flush console content on panic
+ *
+ * Immediately output all pending messages no matter what.
+ */
+void console_flush_on_panic(void)
+{
+	/*
+	 * If someone else is holding the console lock, trylock will fail
+	 * and may_schedule may be set.  Ignore and proceed to unlock so
+	 * that messages are flushed out.  As this can be called from any
+	 * context and we don't want to get preempted while flushing,
+	 * ensure may_schedule is cleared.
+	 */
+	console_trylock();
+	console_may_schedule = 0;
+	console_unlock();
+}
+
 /*
  * Return the console tty driver structure and its associated index
  */
diff --git a/kernel/signal.c b/kernel/signal.c
index 0991539b3..28db04b54 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -3013,11 +3013,9 @@ static int do_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t *info)
 	 * Nor can they impersonate a kill()/tgkill(), which adds source info.
 	 */
 	if ((info->si_code >= 0 || info->si_code == SI_TKILL) &&
-	    (task_pid_vnr(current) != pid)) {
-		/* We used to allow any < 0 si_code */
-		WARN_ON_ONCE(info->si_code < 0);
+	    (task_pid_vnr(current) != pid))
 		return -EPERM;
-	}
+
 	info->si_signo = sig;
 
 	/* POSIX.1b doesn't mention process groups.  */
@@ -3062,12 +3060,10 @@ static int do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info)
 	/* Not even root can pretend to send signals from the kernel.
 	 * Nor can they impersonate a kill()/tgkill(), which adds source info.
 	 */
-	if (((info->si_code >= 0 || info->si_code == SI_TKILL)) &&
-	    (task_pid_vnr(current) != pid)) {
-		/* We used to allow any < 0 si_code */
-		WARN_ON_ONCE(info->si_code < 0);
+	if ((info->si_code >= 0 || info->si_code == SI_TKILL) &&
+	    (task_pid_vnr(current) != pid))
 		return -EPERM;
-	}
+
 	info->si_signo = sig;
 
 	return do_send_specific(tgid, pid, sig, info);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index e5fefe968..781dce655 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -1683,6 +1683,20 @@ static struct ctl_table fs_table[] = {
 		.proc_handler	= &pipe_proc_fn,
 		.extra1		= &pipe_min_size,
 	},
+	{
+		.procname	= "pipe-user-pages-hard",
+		.data		= &pipe_user_pages_hard,
+		.maxlen		= sizeof(pipe_user_pages_hard),
+		.mode		= 0644,
+		.proc_handler	= proc_doulongvec_minmax,
+	},
+	{
+		.procname	= "pipe-user-pages-soft",
+		.data		= &pipe_user_pages_soft,
+		.maxlen		= sizeof(pipe_user_pages_soft),
+		.mode		= 0644,
+		.proc_handler	= proc_doulongvec_minmax,
+	},
 	{ }
 };
 
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 14ffaa59a..9008103db 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -38,6 +38,10 @@ struct trace_bprintk_fmt {
 static inline struct trace_bprintk_fmt *lookup_format(const char *fmt)
 {
 	struct trace_bprintk_fmt *pos;
+
+	if (!fmt)
+		return ERR_PTR(-EINVAL);
+
 	list_for_each_entry(pos, &trace_bprintk_fmt_list, list) {
 		if (!strcmp(pos->fmt, fmt))
 			return pos;
@@ -59,7 +63,8 @@ void hold_module_trace_bprintk_format(const char **start, const char **end)
 	for (iter = start; iter < end; iter++) {
 		struct trace_bprintk_fmt *tb_fmt = lookup_format(*iter);
 		if (tb_fmt) {
-			*iter = tb_fmt->fmt;
+			if (!IS_ERR(tb_fmt))
+				*iter = tb_fmt->fmt;
 			continue;
 		}