summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLennart Poettering <lennart@poettering.net>2014-06-27 18:57:24 +0200
committerLennart Poettering <lennart@poettering.net>2014-06-27 19:35:57 +0200
commit0dc5d23c85db85f96b141d4d32deee8018e56a6a (patch)
tree95d1a57ec4a8f21e3494d61baa77b9b6d3bedffb
parent1f97091d3cb0887c264176b47b0a86c269acf0b5 (diff)
coredump: add simple coredump vacuuming
When disk space taken up by coredumps grows beyond a configured limit start removing the oldest coredump of the user with the most coredumps, until we get below the limit again.
-rw-r--r--.gitignore1
-rw-r--r--Makefile.am16
-rw-r--r--man/coredump.conf.xml20
-rw-r--r--src/journal/coredump-vacuum.c272
-rw-r--r--src/journal/coredump-vacuum.h26
-rw-r--r--src/journal/coredump.c39
-rw-r--r--src/journal/coredump.conf2
-rw-r--r--src/journal/test-coredump-vacuum.c32
8 files changed, 393 insertions, 15 deletions
diff --git a/.gitignore b/.gitignore
index d2e81a271c..fe8c32d42c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -142,6 +142,7 @@
/test-cgroup-util
/test-compress
/test-conf-files
+/test-coredump-vacuum
/test-daemon
/test-date
/test-device-nodes
diff --git a/Makefile.am b/Makefile.am
index e02dede7a1..5d86f3eaec 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -3771,7 +3771,9 @@ systemd_socket_proxyd_LDADD = \
# ------------------------------------------------------------------------------
if ENABLE_COREDUMP
systemd_coredump_SOURCES = \
- src/journal/coredump.c
+ src/journal/coredump.c \
+ src/journal/coredump-vacuum.c \
+ src/journal/coredump-vacuum.h
systemd_coredump_LDADD = \
libsystemd-journal-internal.la \
@@ -3810,6 +3812,18 @@ coredumpctl_LDADD = \
bin_PROGRAMS += \
coredumpctl
+manual_tests += \
+ test-coredump-vacuum
+
+test_coredump_vacuum_SOURCES = \
+ src/journal/test-coredump-vacuum.c \
+ src/journal/coredump-vacuum.c \
+ src/journal/coredump-vacuum.h
+
+test_coredump_vacuum_LDADD = \
+ libsystemd-internal.la \
+ libsystemd-shared.la
+
dist_bashcompletion_DATA += \
shell-completion/bash/coredumpctl
diff --git a/man/coredump.conf.xml b/man/coredump.conf.xml
index 9e4adff46a..e24d958ac4 100644
--- a/man/coredump.conf.xml
+++ b/man/coredump.conf.xml
@@ -121,6 +121,23 @@
<listitem><para>The maximum (uncompressed) size in bytes of a
core to be saved.</para></listitem>
</varlistentry>
+
+ <varlistentry>
+ <term><varname>MaxUse=</varname></term>
+ <term><varname>KeepFree=</varname></term>
+
+ <listitem><para>Enforce limits on the disk space taken up by
+ externally stored coredumps. <option>MaxUse=</option> makes
+ sure that old coredumps are removed as soon as the total disk
+ space taken up by coredumps grows beyond this limit (defaults
+ to 10% of the total disk size). <option>KeepFree=</option>
+ controls how much disk space to keep free at least (defaults
+ to 15% of the total disk size). Note that the disk space used
+ by coredumps might temporarily exceed these limits while
+ coredumps are processed. Note that old coredumps are also
+ removed based on on time via
+ <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>.</para></listitem>
+ </varlistentry>
</variablelist>
</refsect1>
@@ -129,7 +146,8 @@
<title>See Also</title>
<para>
<citerefentry><refentrytitle>systemd-journald.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
- <citerefentry><refentrytitle>coredumpctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+ <citerefentry><refentrytitle>coredumpctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+ <citerefentry><refentrytitle>systemd-tmpfiles</refentrytitle><manvolnum>8</manvolnum></citerefentry>
</para>
</refsect1>
diff --git a/src/journal/coredump-vacuum.c b/src/journal/coredump-vacuum.c
new file mode 100644
index 0000000000..ad2e2fa7f4
--- /dev/null
+++ b/src/journal/coredump-vacuum.c
@@ -0,0 +1,272 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/statvfs.h>
+
+#include "util.h"
+#include "time-util.h"
+#include "hashmap.h"
+#include "macro.h"
+
+#include "coredump-vacuum.h"
+
+#define DEFAULT_MAX_USE_LOWER (off_t) (1ULL*1024ULL*1024ULL) /* 1 MiB */
+#define DEFAULT_MAX_USE_UPPER (off_t) (4ULL*1024ULL*1024ULL*1024ULL) /* 4 GiB */
+#define DEFAULT_KEEP_FREE_UPPER (off_t) (4ULL*1024ULL*1024ULL*1024ULL) /* 4 GiB */
+#define DEFAULT_KEEP_FREE (off_t) (1024ULL*1024ULL) /* 1 MB */
+
+struct vacuum_candidate {
+ unsigned n_files;
+ char *oldest_file;
+ usec_t oldest_mtime;
+};
+
+static void vacuum_candidate_free(struct vacuum_candidate *c) {
+ if (!c)
+ return;
+
+ free(c->oldest_file);
+ free(c);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(struct vacuum_candidate*, vacuum_candidate_free);
+
+static void vacuum_candidate_hasmap_free(Hashmap *h) {
+ struct vacuum_candidate *c;
+
+ while ((c = hashmap_steal_first(h)))
+ vacuum_candidate_free(c);
+
+ hashmap_free(h);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(Hashmap*, vacuum_candidate_hasmap_free);
+
+static int uid_from_file_name(const char *filename, uid_t *uid) {
+ const char *p, *e, *u;
+
+ p = startswith(filename, "core.");
+ if (!p)
+ return -EINVAL;
+
+ /* Skip the comm field */
+ p = strchr(p, '.');
+ if (!p)
+ return -EINVAL;
+ p++;
+
+ /* Find end up UID */
+ e = strchr(p, '.');
+ if (!e)
+ return -EINVAL;
+
+ u = strndupa(p, e-p);
+ return parse_uid(u, uid);
+}
+
+static bool vacuum_necessary(int fd, off_t sum, off_t keep_free, off_t max_use) {
+ off_t fs_size = 0, fs_free = (off_t) -1;
+ struct statvfs sv;
+
+ assert(fd >= 0);
+
+ if (fstatvfs(fd, &sv) >= 0) {
+ fs_size = sv.f_frsize * sv.f_blocks;
+ fs_free = sv.f_frsize * sv.f_bfree;
+ }
+
+ if (max_use == (off_t) -1) {
+
+ if (fs_size > 0) {
+ max_use = PAGE_ALIGN(fs_size / 10); /* 10% */
+
+ if (max_use > DEFAULT_MAX_USE_UPPER)
+ max_use = DEFAULT_MAX_USE_UPPER;
+
+ if (max_use < DEFAULT_MAX_USE_LOWER)
+ max_use = DEFAULT_MAX_USE_LOWER;
+ }
+
+ max_use = DEFAULT_MAX_USE_LOWER;
+ } else
+ max_use = PAGE_ALIGN(max_use);
+
+ if (max_use > 0 && sum > max_use)
+ return true;
+
+ if (keep_free == (off_t) -1) {
+
+ if (fs_size > 0) {
+ keep_free = PAGE_ALIGN((fs_size * 3) / 20); /* 15% */
+
+ if (keep_free > DEFAULT_KEEP_FREE_UPPER)
+ keep_free = DEFAULT_KEEP_FREE_UPPER;
+ } else
+ keep_free = DEFAULT_KEEP_FREE;
+ } else
+ keep_free = PAGE_ALIGN(keep_free);
+
+ if (keep_free > 0 && fs_free < keep_free)
+ return true;
+
+ return false;
+}
+
+int coredump_vacuum(int exclude_fd, off_t keep_free, off_t max_use) {
+ _cleanup_closedir_ DIR *d = NULL;
+ struct stat exclude_st;
+ int r;
+
+ if (keep_free <= 0 && max_use <= 0)
+ return 0;
+
+ if (exclude_fd >= 0) {
+ if (fstat(exclude_fd, &exclude_st) < 0) {
+ log_error("Failed to fstat(): %m");
+ return -errno;
+ }
+ }
+
+ /* This algorithm will keep deleting the oldest file of the
+ * user with the most coredumps until we are back in the size
+ * limits. Note that vacuuming for journal files is different,
+ * because we rely on rate-limiting of the messages there,
+ * to avoid being flooded. */
+
+ d = opendir("/var/lib/systemd/coredump");
+ if (!d) {
+ if (errno == ENOENT)
+ return 0;
+
+ log_error("Can't open coredump directory: %m");
+ return -errno;
+ }
+
+ for (;;) {
+ _cleanup_(vacuum_candidate_hasmap_freep) Hashmap *h = NULL;
+ struct vacuum_candidate *worst = NULL;
+ struct dirent *de;
+ off_t sum = 0;
+
+ rewinddir(d);
+
+ FOREACH_DIRENT(de, d, goto fail) {
+ struct vacuum_candidate *c;
+ struct stat st;
+ uid_t uid;
+ usec_t t;
+
+ r = uid_from_file_name(de->d_name, &uid);
+ if (r < 0)
+ continue;
+
+ if (fstatat(dirfd(d), de->d_name, &st, AT_NO_AUTOMOUNT|AT_SYMLINK_NOFOLLOW) < 0) {
+ if (errno == ENOENT)
+ continue;
+
+ log_warning("Failed to stat /var/lib/systemd/coredump/%s", de->d_name);
+ continue;
+ }
+
+ if (!S_ISREG(st.st_mode))
+ continue;
+
+ if (exclude_fd >= 0 &&
+ exclude_st.st_dev == st.st_dev &&
+ exclude_st.st_ino == st.st_ino)
+ continue;
+
+ r = hashmap_ensure_allocated(&h, NULL, NULL);
+ if (r < 0)
+ return log_oom();
+
+ t = timespec_load(&st.st_mtim);
+
+ c = hashmap_get(h, UINT32_TO_PTR(uid));
+ if (c) {
+
+ if (t < c->oldest_mtime) {
+ char *n;
+
+ n = strdup(de->d_name);
+ if (!n)
+ return log_oom();
+
+ free(c->oldest_file);
+ c->oldest_file = n;
+ c->oldest_mtime = t;
+ }
+
+ } else {
+ _cleanup_(vacuum_candidate_freep) struct vacuum_candidate *n = NULL;
+
+ n = new0(struct vacuum_candidate, 1);
+ if (!n)
+ return log_oom();
+
+ n->oldest_file = strdup(de->d_name);
+ if (!n->oldest_file)
+ return log_oom();
+
+ n->oldest_mtime = t;
+
+ r = hashmap_put(h, UINT32_TO_PTR(uid), n);
+ if (r < 0)
+ return log_oom();
+
+ c = n;
+ n = NULL;
+ }
+
+ c->n_files++;
+
+ if (!worst ||
+ worst->n_files < c->n_files ||
+ (worst->n_files == c->n_files && c->oldest_mtime < worst->oldest_mtime))
+ worst = c;
+
+ sum += st.st_blocks * 512;
+ }
+
+ if (!worst)
+ break;
+
+ r = vacuum_necessary(dirfd(d), sum, keep_free, max_use);
+ if (r <= 0)
+ return r;
+
+ if (unlinkat(dirfd(d), worst->oldest_file, 0) < 0) {
+
+ if (errno == ENOENT)
+ continue;
+
+ log_error("Failed to remove file %s: %m", worst->oldest_file);
+ return -errno;
+ } else
+ log_info("Removed old coredump %s.", worst->oldest_file);
+ }
+
+ return 0;
+
+fail:
+ log_error("Failed to read directory: %m");
+ return -errno;
+}
diff --git a/src/journal/coredump-vacuum.h b/src/journal/coredump-vacuum.h
new file mode 100644
index 0000000000..7ad4399305
--- /dev/null
+++ b/src/journal/coredump-vacuum.h
@@ -0,0 +1,26 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2014 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <sys/types.h>
+
+int coredump_vacuum(int exclude_fd, off_t keep_free, off_t max_use);
diff --git a/src/journal/coredump.c b/src/journal/coredump.c
index ab8fd2cf0e..22e1932e2b 100644
--- a/src/journal/coredump.c
+++ b/src/journal/coredump.c
@@ -42,6 +42,7 @@
#include "stacktrace.h"
#include "path-util.h"
#include "compress.h"
+#include "coredump-vacuum.h"
#ifdef HAVE_ACL
# include <sys/acl.h>
@@ -121,10 +122,11 @@ static DEFINE_CONFIG_PARSE_ENUM(config_parse_coredump_compression, coredump_comp
static CoredumpStorage arg_storage = COREDUMP_STORAGE_EXTERNAL;
static CoredumpCompression arg_compression = COREDUMP_COMPRESSION_XZ;
static unsigned arg_compression_level = LZMA_PRESET_DEFAULT;
-
static off_t arg_process_size_max = PROCESS_SIZE_MAX;
static off_t arg_external_size_max = EXTERNAL_SIZE_MAX;
static size_t arg_journal_size_max = JOURNAL_SIZE_MAX;
+static off_t arg_keep_free = (off_t) -1;
+static off_t arg_max_use = (off_t) -1;
static int parse_config(void) {
@@ -136,6 +138,8 @@ static int parse_config(void) {
{ "Coredump", "ProcessSizeMax", config_parse_iec_off, 0, &arg_process_size_max },
{ "Coredump", "ExternalSizeMax", config_parse_iec_off, 0, &arg_external_size_max },
{ "Coredump", "JournalSizeMax", config_parse_iec_size, 0, &arg_journal_size_max },
+ { "Coredump", "KeepFree", config_parse_iec_off, 0, &arg_keep_free },
+ { "Coredump", "MaxUse", config_parse_iec_off, 0, &arg_max_use },
{}
};
@@ -274,14 +278,14 @@ static int maybe_remove_external_coredump(const char *filename, off_t size) {
return 1;
}
+static int save_external_coredump(
+ const char *info[_INFO_LEN],
+ uid_t uid,
+ char **ret_filename,
+ int *ret_fd,
+ off_t *ret_size) {
-static int save_external_coredump(const char *info[_INFO_LEN],
- uid_t uid,
- char **ret_filename,
- int *ret_fd,
- off_t *ret_size) {
-
- _cleanup_free_ char *p = NULL, *t = NULL, *c = NULL, *fn = NULL, *tmp = NULL;
+ _cleanup_free_ char *p = NULL, *t = NULL, *c = NULL, *fn = NULL, *tmp = NULL, *u = NULL;
_cleanup_close_ int fd = -1;
sd_id128_t boot;
struct stat st;
@@ -300,6 +304,10 @@ static int save_external_coredump(const char *info[_INFO_LEN],
if (!p)
return log_oom();
+ u = filename_escape(info[INFO_UID]);
+ if (!u)
+ return log_oom();
+
t = filename_escape(info[INFO_TIMESTAMP]);
if (!t)
return log_oom();
@@ -311,8 +319,9 @@ static int save_external_coredump(const char *info[_INFO_LEN],
}
r = asprintf(&fn,
- "/var/lib/systemd/coredump/core.%s." SD_ID128_FORMAT_STR ".%s.%s000000",
+ "/var/lib/systemd/coredump/core.%s.%s." SD_ID128_FORMAT_STR ".%s.%s000000",
c,
+ u,
SD_ID128_FORMAT_VAL(boot),
p,
t);
@@ -333,12 +342,10 @@ static int save_external_coredump(const char *info[_INFO_LEN],
r = copy_bytes(STDIN_FILENO, fd, arg_process_size_max);
if (r == -E2BIG) {
- log_error("Coredump of %s (%s) is larger than configured processing limit, refusing.",
- info[INFO_PID], info[INFO_COMM]);
+ log_error("Coredump of %s (%s) is larger than configured processing limit, refusing.", info[INFO_PID], info[INFO_COMM]);
goto fail;
} else if (IN_SET(r, -EDQUOT, -ENOSPC)) {
- log_error("Not enough disk space for coredump of %s (%s), refusing.",
- info[INFO_PID], info[INFO_COMM]);
+ log_error("Not enough disk space for coredump of %s (%s), refusing.", info[INFO_PID], info[INFO_COMM]);
goto fail;
} else if (r < 0) {
log_error("Failed to dump coredump to file: %s", strerror(-r));
@@ -646,6 +653,9 @@ int main(int argc, char* argv[]) {
IOVEC_SET_STRING(iovec[j++], "MESSAGE_ID=fc2e22bc6ee647b6b90729ab34a250b1");
IOVEC_SET_STRING(iovec[j++], "PRIORITY=2");
+ /* Vacuum before we write anything again */
+ coredump_vacuum(-1, arg_keep_free, arg_max_use);
+
/* Always stream the coredump to disk, if that's possible */
r = save_external_coredump(info, uid, &filename, &coredump_fd, &coredump_size);
if (r < 0)
@@ -666,6 +676,9 @@ int main(int argc, char* argv[]) {
IOVEC_SET_STRING(iovec[j++], coredump_filename);
}
+ /* Vacuum again, but exclude the coredump we just created */
+ coredump_vacuum(coredump_fd, arg_keep_free, arg_max_use);
+
/* Now, let's drop privileges to become the user who owns the
* segfaulted process and allocate the coredump memory under
* his uid. This also ensures that the credentials journald
diff --git a/src/journal/coredump.conf b/src/journal/coredump.conf
index 9f4edd34d9..050bde6491 100644
--- a/src/journal/coredump.conf
+++ b/src/journal/coredump.conf
@@ -15,3 +15,5 @@
#ProcessSizeMax=2G
#ExternalSizeMax=2G
#JournalSizeMax=767M
+#MaxUse=
+#KeepFree=
diff --git a/src/journal/test-coredump-vacuum.c b/src/journal/test-coredump-vacuum.c
new file mode 100644
index 0000000000..a4dd00125d
--- /dev/null
+++ b/src/journal/test-coredump-vacuum.c
@@ -0,0 +1,32 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2012 Zbigniew Jędrzejewski-Szmek
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd is distributed in the hope that it will be useful, but
+ WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdlib.h>
+
+#include "coredump-vacuum.h"
+
+int main(int argc, char *argv[]) {
+
+ if (coredump_vacuum(-1, (off_t) -1, 70 * 1024) < 0)
+ return EXIT_FAILURE;
+
+ return EXIT_SUCCESS;
+}