linux/fs/xfs/xfs_stats.c
Takashi Iwai 17bb60b741 xfs: Use scnprintf() for avoiding potential buffer overflow
Since snprintf() returns the would-be-output size instead of the
actual output size, the succeeding calls may go beyond the given
buffer limit.  Fix it by replacing with scnprintf().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
2020-03-12 07:58:13 -07:00

161 lines
4.2 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* Copyright (c) 2000-2003,2005 Silicon Graphics, Inc.
* All Rights Reserved.
*/
#include "xfs.h"
struct xstats xfsstats;
static int counter_val(struct xfsstats __percpu *stats, int idx)
{
int val = 0, cpu;
for_each_possible_cpu(cpu)
val += *(((__u32 *)per_cpu_ptr(stats, cpu) + idx));
return val;
}
int xfs_stats_format(struct xfsstats __percpu *stats, char *buf)
{
int i, j;
int len = 0;
uint64_t xs_xstrat_bytes = 0;
uint64_t xs_write_bytes = 0;
uint64_t xs_read_bytes = 0;
static const struct xstats_entry {
char *desc;
int endpoint;
} xstats[] = {
{ "extent_alloc", xfsstats_offset(xs_abt_lookup) },
{ "abt", xfsstats_offset(xs_blk_mapr) },
{ "blk_map", xfsstats_offset(xs_bmbt_lookup) },
{ "bmbt", xfsstats_offset(xs_dir_lookup) },
{ "dir", xfsstats_offset(xs_trans_sync) },
{ "trans", xfsstats_offset(xs_ig_attempts) },
{ "ig", xfsstats_offset(xs_log_writes) },
{ "log", xfsstats_offset(xs_try_logspace)},
{ "push_ail", xfsstats_offset(xs_xstrat_quick)},
{ "xstrat", xfsstats_offset(xs_write_calls) },
{ "rw", xfsstats_offset(xs_attr_get) },
{ "attr", xfsstats_offset(xs_iflush_count)},
{ "icluster", xfsstats_offset(vn_active) },
{ "vnodes", xfsstats_offset(xb_get) },
{ "buf", xfsstats_offset(xs_abtb_2) },
{ "abtb2", xfsstats_offset(xs_abtc_2) },
{ "abtc2", xfsstats_offset(xs_bmbt_2) },
{ "bmbt2", xfsstats_offset(xs_ibt_2) },
{ "ibt2", xfsstats_offset(xs_fibt_2) },
{ "fibt2", xfsstats_offset(xs_rmap_2) },
{ "rmapbt", xfsstats_offset(xs_refcbt_2) },
{ "refcntbt", xfsstats_offset(xs_qm_dqreclaims)},
/* we print both series of quota information together */
{ "qm", xfsstats_offset(xs_xstrat_bytes)},
};
/* Loop over all stats groups */
for (i = j = 0; i < ARRAY_SIZE(xstats); i++) {
len += scnprintf(buf + len, PATH_MAX - len, "%s",
xstats[i].desc);
/* inner loop does each group */
for (; j < xstats[i].endpoint; j++)
len += scnprintf(buf + len, PATH_MAX - len, " %u",
counter_val(stats, j));
len += scnprintf(buf + len, PATH_MAX - len, "\n");
}
/* extra precision counters */
for_each_possible_cpu(i) {
xs_xstrat_bytes += per_cpu_ptr(stats, i)->s.xs_xstrat_bytes;
xs_write_bytes += per_cpu_ptr(stats, i)->s.xs_write_bytes;
xs_read_bytes += per_cpu_ptr(stats, i)->s.xs_read_bytes;
}
len += scnprintf(buf + len, PATH_MAX-len, "xpc %Lu %Lu %Lu\n",
xs_xstrat_bytes, xs_write_bytes, xs_read_bytes);
len += scnprintf(buf + len, PATH_MAX-len, "debug %u\n",
#if defined(DEBUG)
1);
#else
0);
#endif
return len;
}
void xfs_stats_clearall(struct xfsstats __percpu *stats)
{
int c;
uint32_t vn_active;
xfs_notice(NULL, "Clearing xfsstats");
for_each_possible_cpu(c) {
preempt_disable();
/* save vn_active, it's a universal truth! */
vn_active = per_cpu_ptr(stats, c)->s.vn_active;
memset(per_cpu_ptr(stats, c), 0, sizeof(*stats));
per_cpu_ptr(stats, c)->s.vn_active = vn_active;
preempt_enable();
}
}
#ifdef CONFIG_PROC_FS
/* legacy quota interfaces */
#ifdef CONFIG_XFS_QUOTA
#define XFSSTAT_START_XQMSTAT xfsstats_offset(xs_qm_dqreclaims)
#define XFSSTAT_END_XQMSTAT xfsstats_offset(xs_qm_dquot)
static int xqm_proc_show(struct seq_file *m, void *v)
{
/* maximum; incore; ratio free to inuse; freelist */
seq_printf(m, "%d\t%d\t%d\t%u\n",
0, counter_val(xfsstats.xs_stats, XFSSTAT_END_XQMSTAT),
0, counter_val(xfsstats.xs_stats, XFSSTAT_END_XQMSTAT + 1));
return 0;
}
/* legacy quota stats interface no 2 */
static int xqmstat_proc_show(struct seq_file *m, void *v)
{
int j;
seq_printf(m, "qm");
for (j = XFSSTAT_START_XQMSTAT; j < XFSSTAT_END_XQMSTAT; j++)
seq_printf(m, " %u", counter_val(xfsstats.xs_stats, j));
seq_putc(m, '\n');
return 0;
}
#endif /* CONFIG_XFS_QUOTA */
int
xfs_init_procfs(void)
{
if (!proc_mkdir("fs/xfs", NULL))
return -ENOMEM;
if (!proc_symlink("fs/xfs/stat", NULL,
"/sys/fs/xfs/stats/stats"))
goto out;
#ifdef CONFIG_XFS_QUOTA
if (!proc_create_single("fs/xfs/xqmstat", 0, NULL, xqmstat_proc_show))
goto out;
if (!proc_create_single("fs/xfs/xqm", 0, NULL, xqm_proc_show))
goto out;
#endif
return 0;
out:
remove_proc_subtree("fs/xfs", NULL);
return -ENOMEM;
}
void
xfs_cleanup_procfs(void)
{
remove_proc_subtree("fs/xfs", NULL);
}
#endif /* CONFIG_PROC_FS */