linux-kernel - [PATCH 5.10 096/199] printk: fix kmsg_dump_get

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:   Mon, 25 Jan 2021 19:38:38 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, John Ogness <john.ogness@...utronix.de>,
        Petr Mladek <pmladek@...e.com>,
        Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.10 096/199] printk: fix kmsg_dump_get_buffer length calulations

From: John Ogness <john.ogness@...utronix.de>

[ Upstream commit 89ccf18f032f26946e2ea6258120472eec6aa745 ]

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: e2ae715d66bf ("kmsg - kmsg_dump() use iterator to receive log buffer content")
Signed-off-by: John Ogness <john.ogness@...utronix.de>
Reviewed-by: Petr Mladek <pmladek@...e.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@...il.com>
Signed-off-by: Petr Mladek <pmladek@...e.com>
Link: https://lore.kernel.org/r/20210113164413.1599-1-john.ogness@linutronix.de
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 kernel/printk/printk.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -3376,7 +3376,7 @@ bool kmsg_dump_get_buffer(struct kmsg_du
 	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;
 	}
 
@@ -3386,7 +3386,7 @@ bool kmsg_dump_get_buffer(struct kmsg_du
 						&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;
 	}