Commit cf5b0208 authored by John Ogness's avatar John Ogness Committed by Petr Mladek
Browse files

printk: introduce CONSOLE_LOG_MAX 



Instead of using "LOG_LINE_MAX + PREFIX_MAX" for temporary buffer
sizes, introduce CONSOLE_LOG_MAX. This represents the maximum size
that is allowed to be printed to the console for a single record.

Signed-off-by: default avatarJohn Ogness <john.ogness@linutronix.de>
Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210303101528.29901-8-john.ogness@linutronix.de
parent 4260e0e5

kernel/printk/printk.c

+12 −8
Original line number Diff line number Diff line
@@ -410,7 +410,12 @@ static u64 clear_seq; 
#else

#define PREFIX_MAX		32

#endif

#define LOG_LINE_MAX		(1024 - PREFIX_MAX)



/* the maximum size of a formatted record (i.e. with prefix added per line) */

#define CONSOLE_LOG_MAX		1024



/* the maximum size allowed to be reserved for a record */

#define LOG_LINE_MAX		(CONSOLE_LOG_MAX - PREFIX_MAX)



#define LOG_LEVEL(v)		((v) & 0x07)

#define LOG_FACILITY(v)		((v) >> 3 & 0xff)
@@ -1472,11 +1477,11 @@ static int syslog_print(char __user *buf, int size) 
	char *text;

	int len = 0;



	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);

	text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);

	if (!text)

		return -ENOMEM;



	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);

	prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);



	while (size > 0) {

		size_t n;
@@ -1542,7 +1547,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear) 
	u64 seq;

	bool time;



	text = kmalloc(LOG_LINE_MAX + PREFIX_MAX, GFP_KERNEL);

	text = kmalloc(CONSOLE_LOG_MAX, GFP_KERNEL);

	if (!text)

		return -ENOMEM;
@@ -1554,7 +1559,7 @@ static int syslog_print_all(char __user *buf, int size, bool clear) 
	 */

	seq = find_first_fitting_seq(clear_seq, -1, size, true, time);



	prb_rec_init_rd(&r, &info, text, LOG_LINE_MAX + PREFIX_MAX);

	prb_rec_init_rd(&r, &info, text, CONSOLE_LOG_MAX);



	len = 0;

	prb_for_each_record(seq, prb, seq, &r) {
@@ -2187,8 +2192,7 @@ EXPORT_SYMBOL(printk); 


#else /* CONFIG_PRINTK */



#define LOG_LINE_MAX		0

#define PREFIX_MAX		0

#define CONSOLE_LOG_MAX		0

#define printk_time		false



#define prb_read_valid(rb, seq, r)	false
@@ -2506,7 +2510,7 @@ static inline int can_use_console(void) 
void console_unlock(void)

{

	static char ext_text[CONSOLE_EXT_LOG_MAX];

	static char text[LOG_LINE_MAX + PREFIX_MAX];

	static char text[CONSOLE_LOG_MAX];

	unsigned long flags;

	bool do_cond_resched, retry;

	struct printk_info info;