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2.31-2: dmesg fix

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This commit is contained in:
Karel Zak 2017-10-30 15:20:51 +01:00
parent 3251a896f8
commit 4420515181
2 changed files with 201 additions and 1 deletions
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194
0001-Revert-dmesg-fragment-concatenation.patch Normal file
View File

@ -0,0 +1,194 @@
From 8a6f0cfd96a3a7f0e72079407af4b8ed705c1ed2 Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Mon, 30 Oct 2017 15:04:20 +0100
Subject: [PATCH] Revert "dmesg: fragment concatenation"
* introduces regressions
* stupid code; parse_kmsg_record() called more than once for each record
This reverts commit 22eb2f0190d8a9850da750641439ccd284ac0bfe.
---
sys-utils/dmesg.c | 117 ++++--------------------------------------------------
1 file changed, 7 insertions(+), 110 deletions(-)
diff --git a/sys-utils/dmesg.c b/sys-utils/dmesg.c
index b626380f7..6e5911a76 100644
--- a/sys-utils/dmesg.c
+++ b/sys-utils/dmesg.c
@@ -20,7 +20,6 @@
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
-#include <poll.h>
#include "c.h"
#include "colors.h"
@@ -179,8 +178,6 @@ struct dmesg_control {
int kmsg; /* /dev/kmsg file descriptor */
ssize_t kmsg_first_read;/* initial read() return code */
char kmsg_buf[BUFSIZ];/* buffer to read kmsg data */
- char kmsg_saved[BUFSIZ];/* buffer to save line after fragment */
- ssize_t kmsg_saved_size; /* if nonzero, read from kmsg_saved */
/*
* For the --file option we mmap whole file. The unnecessary (already
@@ -209,7 +206,6 @@ struct dmesg_record {
int level;
int facility;
struct timeval tv;
- char flags;
const char *next; /* buffer with next unparsed record */
size_t next_size; /* size of the next buffer */
@@ -226,13 +222,6 @@ struct dmesg_record {
static int read_kmsg(struct dmesg_control *ctl);
-
-static int parse_kmsg_record(struct dmesg_control *ctl,
- struct dmesg_record *rec,
- char *buf,
- size_t sz);
-
-
static int set_level_color(int log_level, const char *mesg, size_t mesgsz)
{
int id = -1;
@@ -1024,101 +1013,15 @@ static void print_buffer(struct dmesg_control *ctl,
print_record(ctl, &rec);
}
-/*
- * Read one record from kmsg, automatically concatenating message fragments
- */
static ssize_t read_kmsg_one(struct dmesg_control *ctl)
{
ssize_t size;
- struct dmesg_record rec = { .flags = 0 };
- char fragment_buf[BUFSIZ] = { 0 };
- ssize_t fragment_offset = 0;
-
- if (ctl->kmsg_saved_size != 0) {
- size = ctl->kmsg_saved_size;
- memcpy(ctl->kmsg_buf, ctl->kmsg_saved, size);
- ctl->kmsg_saved_size = 0;
- return size;
- }
- /*
- * kmsg returns EPIPE if record was modified while reading.
- * Read records until there is one with a flag different from 'c'/'+',
- * which indicates that a fragment (if it exists) is complete.
- */
+ /* kmsg returns EPIPE if record was modified while reading */
do {
- /*
- * If there is a fragment in progress, and we're in follow mode,
- * read with a timeout so that if no line is read in 100ms, we can
- * assume that the fragment is the last line in /dev/kmsg and it
- * is completed.
- */
- if (ctl->follow && fragment_offset) {
- struct pollfd pfd = {.fd = ctl->kmsg, .events = POLLIN};
- poll(&pfd, 1, 100);
- /* If 100ms has passed and kmsg has no data to read() */
- if (!(pfd.revents & POLLIN)) {
- memcpy(ctl->kmsg_buf, fragment_buf, fragment_offset);
- return fragment_offset + 1;
- }
- }
- size = read(ctl->kmsg, ctl->kmsg_buf, sizeof(ctl->kmsg_buf) - 1);
-
- /*
- * If read() would have blocked and we have a fragment in
- * progress, assume that it's completed (ie. it was the last line
- * in the ring buffer) otherwise it won't be displayed until
- * another non-fragment message is logged.
- */
- if (errno == EAGAIN && fragment_offset) {
- memcpy(ctl->kmsg_buf, fragment_buf, fragment_offset);
- return fragment_offset + 1;
- }
-
- if (parse_kmsg_record(ctl, &rec, ctl->kmsg_buf,
- (size_t) size) == 0) {
- /*
- * 'c' can indicate a start of a fragment or a
- * continuation, '+' is used in older kernels to
- * indicate a continuation.
- */
- if (rec.flags == 'c' || rec.flags == '+') {
- if (!fragment_offset) {
- memcpy(fragment_buf, ctl->kmsg_buf, size);
- fragment_offset = size - 1;
- } else {
- /*
- * In case of a buffer overflow, just
- * truncate the fragment - no one should
- * be logging this much anyway
- */
- ssize_t truncate_size = min(
- fragment_offset + rec.mesg_size,
- sizeof(fragment_buf));
-
- memcpy(fragment_buf + fragment_offset,
- rec.mesg, truncate_size);
- fragment_offset += rec.mesg_size;
- }
-
- } else if (rec.flags == '-') {
- /*
- * If there was a fragment being built, move it
- * into kmsg_buf, but first save a copy of the
- * current message so that it doesn't get lost.
- */
- if (fragment_offset) {
- memcpy(ctl->kmsg_saved,
- ctl->kmsg_buf, size);
- ctl->kmsg_saved_size = size;
- memcpy(ctl->kmsg_buf,
- fragment_buf, fragment_offset);
- return fragment_offset + 1;
- }
- }
- }
- } while ((size < 0 && errno == EPIPE) ||
- (rec.flags == 'c' || rec.flags == '+'));
+ size = read(ctl->kmsg, ctl->kmsg_buf,
+ sizeof(ctl->kmsg_buf) - 1);
+ } while (size < 0 && errno == EPIPE);
return size;
}
@@ -1212,17 +1115,11 @@ static int parse_kmsg_record(struct dmesg_control *ctl,
if (LAST_KMSG_FIELD(p))
goto mesg;
- /* D) flags */
- rec->flags = *p; // flag is one char
- p = p + 1;
- if (LAST_KMSG_FIELD(p))
- goto mesg;
-
- /* E) optional fields (ignore) */
+ /* D) optional fields (ignore) */
p = skip_item(p, end, ";");
mesg:
- /* F) message text */
+ /* E) message text */
rec->mesg = p;
p = skip_item(p, end, "\n");
@@ -1238,7 +1135,7 @@ mesg:
*/
unhexmangle_to_buffer(rec->mesg, (char *) rec->mesg, rec->mesg_size + 1);
- /* G) message tags (ignore) */
+ /* F) message tags (ignore) */
return 0;
}
--
2.13.6

8
util-linux.spec
View File

@ -2,7 +2,7 @@
Summary: A collection of basic system utilities Summary: A collection of basic system utilities
Name: util-linux Name: util-linux
Version: 2.31 Version: 2.31
Release: 1%{?dist} Release: 2%{?dist}
License: GPLv2 and GPLv2+ and LGPLv2+ and BSD with advertising and Public Domain License: GPLv2 and GPLv2+ and LGPLv2+ and BSD with advertising and Public Domain
Group: System Environment/Base Group: System Environment/Base
URL: http://en.wikipedia.org/wiki/Util-linux URL: http://en.wikipedia.org/wiki/Util-linux
@ -92,6 +92,9 @@ Requires: libfdisk = %{version}-%{release}
# 151635 - makeing /var/log/lastlog # 151635 - makeing /var/log/lastlog
Patch0: 2.28-login-lastlog-create.patch Patch0: 2.28-login-lastlog-create.patch
# upstream
Patch1: 0001-Revert-dmesg-fragment-concatenation.patch
%description %description
The util-linux package contains a large variety of low-level system The util-linux package contains a large variety of low-level system
utilities that are necessary for a Linux system to function. Among utilities that are necessary for a Linux system to function. Among
@ -940,6 +943,9 @@ exit 0
%{_libdir}/python*/site-packages/libmount/* %{_libdir}/python*/site-packages/libmount/*
%changelog %changelog
* Mon Oct 30 2017 Karel Zak <kzak@redhat.com> - 2.31-2
- fix dmesg for multi-line records
* Mon Oct 23 2017 Karel Zak <kzak@redhat.com> - 2.31-1 * Mon Oct 23 2017 Karel Zak <kzak@redhat.com> - 2.31-1
- upgrade to final v2.31 - upgrade to final v2.31
- move rfkill to sbin (for backward compatibility) - move rfkill to sbin (for backward compatibility)