Commit 89ccf18f authored by John Ogness's avatar John Ogness Committed by Petr Mladek
Browse files

printk: fix kmsg_dump_get_buffer length calulations 



kmsg_dump_get_buffer() uses @syslog to determine if the syslog
prefix should be written to the buffer. However, when calculating
the maximum number of records that can fit into the buffer, it
always counts the bytes from the syslog prefix.

Use @syslog when calculating the maximum number of records that can
fit into the buffer.

Fixes: e2ae715d ("kmsg - kmsg_dump() use iterator to receive log buffer content")
Signed-off-by: default avatarJohn Ogness <john.ogness@linutronix.de>
Reviewed-by: default avatarPetr Mladek <pmladek@suse.com>
Acked-by: default avatarSergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: default avatarPetr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20210113164413.1599-1-john.ogness@linutronix.de
parent 668af87f

kernel/printk/printk.c

+2 −2
Original line number Diff line number Diff line
@@ -3423,7 +3423,7 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog, 
	while (prb_read_valid_info(prb, seq, &info, &line_count)) {

		if (r.info->seq >= dumper->next_seq)

			break;

		l += get_record_print_text_size(&info, line_count, true, time);

		l += get_record_print_text_size(&info, line_count, syslog, time);

		seq = r.info->seq + 1;

	}
@@ -3433,7 +3433,7 @@ bool kmsg_dump_get_buffer(struct kmsg_dumper *dumper, bool syslog, 
						&info, &line_count)) {

		if (r.info->seq >= dumper->next_seq)

			break;

		l -= get_record_print_text_size(&info, line_count, true, time);

		l -= get_record_print_text_size(&info, line_count, syslog, time);

		seq = r.info->seq + 1;

	}