[PATCH] printk: fix kmsg_dump_get_buffer length calulations

From: John Ogness
Date: Wed Jan 13 2021 - 11:44:58 EST


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@xxxxxxxxxxxxx>
---
kernel/printk/printk.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c
index ffdd0dc7ec6d..848b56efc9d7 100644
--- a/kernel/printk/printk.c
+++ b/kernel/printk/printk.c
@@ -3427,7 +3427,7 @@ 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;
}

@@ -3437,7 +3437,7 @@ 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;
}

--
2.20.1