linux-kernel - [PATCH v2 1/3] printk: Split the code for storing a message into the log buffer

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 27 Jun 2018 16:08:15 +0200
From:   Petr Mladek <pmladek@...e.com>
To:     Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
        Steven Rostedt <rostedt@...dmis.org>
Cc:     Peter Zijlstra <peterz@...radead.org>,
        Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>,
        Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>,
        linux-kernel@...r.kernel.org, stable@...r.kernel.org,
        Petr Mladek <pmladek@...e.com>
Subject: [PATCH v2 1/3] printk: Split the code for storing a message into the log buffer

It is just a preparation step. The patch does not change
the existing behavior.

Signed-off-by: Petr Mladek <pmladek@...e.com>
---
 kernel/printk/printk.c | 43 ++++++++++++++++++++++++++-----------------
 1 file changed, 26 insertions(+), 17 deletions(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index 247808333ba4..a844c611b17c 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -1824,28 +1824,16 @@ static size_t log_output(int facility, int level, enum log_flags lflags, const c
 	return log_store(facility, level, lflags, 0, dict, dictlen, text, text_len);
 }
 
-asmlinkage int vprintk_emit(int facility, int level,
-			    const char *dict, size_t dictlen,
-			    const char *fmt, va_list args)
+/* Must be called under logbuf_lock. */
+int vprintk_store(int facility, int level,
+		  const char *dict, size_t dictlen,
+		  const char *fmt, va_list args)
 {
 	static char textbuf[LOG_LINE_MAX];
 	char *text = textbuf;
 	size_t text_len;
 	enum log_flags lflags = 0;
-	unsigned long flags;
-	int printed_len;
-	bool in_sched = false;
-
-	if (level == LOGLEVEL_SCHED) {
-		level = LOGLEVEL_DEFAULT;
-		in_sched = true;
-	}
-
-	boot_delay_msec(level);
-	printk_delay();
 
-	/* This stops the holder of console_sem just where we want him */
-	logbuf_lock_irqsave(flags);
 	/*
 	 * The printf needs to come first; we need the syslog
 	 * prefix which might be passed-in as a parameter.
@@ -1886,8 +1874,29 @@ asmlinkage int vprintk_emit(int facility, int level,
 	if (dict)
 		lflags |= LOG_PREFIX|LOG_NEWLINE;
 
-	printed_len = log_output(facility, level, lflags, dict, dictlen, text, text_len);
+	return log_output(facility, level, lflags,
+			  dict, dictlen, text, text_len);
+}
 
+asmlinkage int vprintk_emit(int facility, int level,
+			    const char *dict, size_t dictlen,
+			    const char *fmt, va_list args)
+{
+	int printed_len;
+	bool in_sched = false;
+	unsigned long flags;
+
+	if (level == LOGLEVEL_SCHED) {
+		level = LOGLEVEL_DEFAULT;
+		in_sched = true;
+	}
+
+	boot_delay_msec(level);
+	printk_delay();
+
+	/* This stops the holder of console_sem just where we want him */
+	logbuf_lock_irqsave(flags);
+	printed_len = vprintk_store(facility, level, dict, dictlen, fmt, args);
 	logbuf_unlock_irqrestore(flags);
 
 	/* If called from the scheduler, we can not call up(). */
-- 
2.13.7