[PATCH 46/47] staging/lustre: Fix unsafe userspace access in many proc files
From: Oleg Drokin
Date: Sun Apr 27 2014 - 13:09:30 EST
Apparently we are pretty bad about verifying our buffers passed
from userspace.
Signed-off-by: Oleg Drokin <oleg.drokin@xxxxxxxxx>
Reviewed-on: http://review.whamcloud.com/9059
Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-4563
Reviewed-by: Dmitry Eremin <dmitry.eremin@xxxxxxxxx>
Reviewed-by: James Simmons <uja.ornl@xxxxxxxxx>
---
drivers/staging/lustre/lustre/fid/lproc_fid.c | 41 +++++++---
.../lustre/lustre/include/lustre/lustre_idl.h | 2 +-
drivers/staging/lustre/lustre/llite/lproc_llite.c | 91 +++++++++++++++++-----
.../lustre/lustre/obdclass/linux/linux-module.c | 9 ++-
drivers/staging/lustre/lustre/osc/lproc_osc.c | 16 +++-
5 files changed, 124 insertions(+), 35 deletions(-)
diff --git a/drivers/staging/lustre/lustre/fid/lproc_fid.c b/drivers/staging/lustre/lustre/fid/lproc_fid.c
index ddd813c..6f5674d 100644
--- a/drivers/staging/lustre/lustre/fid/lproc_fid.c
+++ b/drivers/staging/lustre/lustre/fid/lproc_fid.c
@@ -54,32 +54,49 @@
#include <lustre_fid.h>
#include "fid_internal.h"
+/* Format: [0x64BIT_INT - 0x64BIT_INT] + 32 bytes just in case */
+#define MAX_FID_RANGE_STRLEN (32 + 2 * 2 * sizeof(__u64))
/*
* Note: this function is only used for testing, it is no safe for production
* use.
*/
-static int
-lprocfs_fid_write_common(const char *buffer, unsigned long count,
- struct lu_seq_range *range)
+static int lprocfs_fid_write_common(const char __user *buffer, size_t count,
+ struct lu_seq_range *range)
{
struct lu_seq_range tmp;
int rc;
+ char kernbuf[MAX_FID_RANGE_STRLEN];
LASSERT(range != NULL);
- rc = sscanf(buffer, "[%llx - %llx]\n",
+ if (count >= sizeof(kernbuf))
+ return -EINVAL;
+
+ if (copy_from_user(kernbuf, buffer, count))
+ return -EFAULT;
+
+ kernbuf[count] = 0;
+
+ if (count == 5 && strcmp(kernbuf, "clear") == 0) {
+ memset(range, 0, sizeof(*range));
+ return count;
+ }
+
+ /* of the form "[0x0000000240000400 - 0x000000028000400]" */
+ rc = sscanf(kernbuf, "[%llx - %llx]\n",
(long long unsigned *)&tmp.lsr_start,
(long long unsigned *)&tmp.lsr_end);
- if (rc != 2 || !range_is_sane(&tmp) || range_is_zero(&tmp))
+ if (!range_is_sane(&tmp) || range_is_zero(&tmp) ||
+ tmp.lsr_start < range->lsr_start || tmp.lsr_end > range->lsr_end)
return -EINVAL;
*range = tmp;
- return 0;
+ return count;
}
/* Client side procfs stuff */
-static ssize_t
-lprocfs_fid_space_seq_write(struct file *file, const char *buffer,
- size_t count, loff_t *off)
+static ssize_t lprocfs_fid_space_seq_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *off)
{
struct lu_client_seq *seq = ((struct seq_file *)file->private_data)->private;
int rc;
@@ -114,9 +131,9 @@ lprocfs_fid_space_seq_show(struct seq_file *m, void *unused)
return rc;
}
-static ssize_t
-lprocfs_fid_width_seq_write(struct file *file, const char *buffer,
- size_t count, loff_t *off)
+static ssize_t lprocfs_fid_width_seq_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *off)
{
struct lu_client_seq *seq = ((struct seq_file *)file->private_data)->private;
__u64 max;
diff --git a/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h b/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h
index abd29bf..83014c9 100644
--- a/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h
+++ b/drivers/staging/lustre/lustre/include/lustre/lustre_idl.h
@@ -265,7 +265,7 @@ static inline __u64 range_space(const struct lu_seq_range *range)
static inline void range_init(struct lu_seq_range *range)
{
- range->lsr_start = range->lsr_end = range->lsr_index = 0;
+ memset(range, 0, sizeof(*range));
}
/**
diff --git a/drivers/staging/lustre/lustre/llite/lproc_llite.c b/drivers/staging/lustre/lustre/llite/lproc_llite.c
index 6d70c65..77ee9e5 100644
--- a/drivers/staging/lustre/lustre/llite/lproc_llite.c
+++ b/drivers/staging/lustre/lustre/llite/lproc_llite.c
@@ -367,8 +367,9 @@ static int ll_max_cached_mb_seq_show(struct seq_file *m, void *v)
cache->ccc_lru_shrinkers);
}
-static ssize_t ll_max_cached_mb_seq_write(struct file *file, const char *buffer,
- size_t count, loff_t *off)
+static ssize_t ll_max_cached_mb_seq_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *off)
{
struct super_block *sb = ((struct seq_file *)file->private_data)->private;
struct ll_sb_info *sbi = ll_s2sbi(sb);
@@ -376,9 +377,18 @@ static ssize_t ll_max_cached_mb_seq_write(struct file *file, const char *buffer,
int mult, rc, pages_number;
int diff = 0;
int nrpages = 0;
+ char kernbuf[128];
+
+ if (count >= sizeof(kernbuf))
+ return -EINVAL;
+
+ if (copy_from_user(kernbuf, buffer, count))
+ return -EFAULT;
+ kernbuf[count] = 0;
mult = 1 << (20 - PAGE_CACHE_SHIFT);
- buffer = lprocfs_find_named_value(buffer, "max_cached_mb:", &count);
+ buffer += lprocfs_find_named_value(kernbuf, "max_cached_mb:", &count) -
+ kernbuf;
rc = lprocfs_write_frac_helper(buffer, count, &pages_number, mult);
if (rc)
return rc;
@@ -1163,7 +1173,8 @@ static int ll_rw_extents_stats_pp_seq_show(struct seq_file *seq, void *v)
}
static ssize_t ll_rw_extents_stats_pp_seq_write(struct file *file,
- const char *buf, size_t len,
+ const char __user *buf,
+ size_t len,
loff_t *off)
{
struct seq_file *seq = file->private_data;
@@ -1172,10 +1183,24 @@ static ssize_t ll_rw_extents_stats_pp_seq_write(struct file *file,
int i;
int value = 1, rc = 0;
+ if (len == 0)
+ return -EINVAL;
+
rc = lprocfs_write_helper(buf, len, &value);
- if (rc < 0 && (strcmp(buf, "disabled") == 0 ||
- strcmp(buf, "Disabled") == 0))
- value = 0;
+ if (rc < 0 && len < 16) {
+ char kernbuf[16];
+
+ if (copy_from_user(kernbuf, buf, len))
+ return -EFAULT;
+ kernbuf[len] = 0;
+
+ if (kernbuf[len - 1] == '\n')
+ kernbuf[len - 1] = 0;
+
+ if (strcmp(kernbuf, "disabled") == 0 ||
+ strcmp(kernbuf, "Disabled") == 0)
+ value = 0;
+ }
if (value == 0)
sbi->ll_rw_stats_on = 0;
@@ -1222,8 +1247,9 @@ static int ll_rw_extents_stats_seq_show(struct seq_file *seq, void *v)
return 0;
}
-static ssize_t ll_rw_extents_stats_seq_write(struct file *file, const char *buf,
- size_t len, loff_t *off)
+static ssize_t ll_rw_extents_stats_seq_write(struct file *file,
+ const char __user *buf,
+ size_t len, loff_t *off)
{
struct seq_file *seq = file->private_data;
struct ll_sb_info *sbi = seq->private;
@@ -1231,15 +1257,30 @@ static ssize_t ll_rw_extents_stats_seq_write(struct file *file, const char *buf,
int i;
int value = 1, rc = 0;
+ if (len == 0)
+ return -EINVAL;
+
rc = lprocfs_write_helper(buf, len, &value);
- if (rc < 0 && (strcmp(buf, "disabled") == 0 ||
- strcmp(buf, "Disabled") == 0))
- value = 0;
+ if (rc < 0 && len < 16) {
+ char kernbuf[16];
+
+ if (copy_from_user(kernbuf, buf, len))
+ return -EFAULT;
+ kernbuf[len] = 0;
+
+ if (kernbuf[len - 1] == '\n')
+ kernbuf[len - 1] = 0;
+
+ if (strcmp(kernbuf, "disabled") == 0 ||
+ strcmp(kernbuf, "Disabled") == 0)
+ value = 0;
+ }
if (value == 0)
sbi->ll_rw_stats_on = 0;
else
sbi->ll_rw_stats_on = 1;
+
spin_lock(&sbi->ll_pp_extent_lock);
for (i = 0; i <= LL_PROCESS_HIST_MAX; i++) {
io_extents->pp_extents[i].pid = 0;
@@ -1250,7 +1291,6 @@ static ssize_t ll_rw_extents_stats_seq_write(struct file *file, const char *buf,
return len;
}
-
LPROC_SEQ_FOPS(ll_rw_extents_stats);
void ll_rw_stats_tally(struct ll_sb_info *sbi, pid_t pid,
@@ -1410,8 +1450,9 @@ static int ll_rw_offset_stats_seq_show(struct seq_file *seq, void *v)
return 0;
}
-static ssize_t ll_rw_offset_stats_seq_write(struct file *file, const char *buf,
- size_t len, loff_t *off)
+static ssize_t ll_rw_offset_stats_seq_write(struct file *file,
+ const char __user *buf,
+ size_t len, loff_t *off)
{
struct seq_file *seq = file->private_data;
struct ll_sb_info *sbi = seq->private;
@@ -1419,11 +1460,25 @@ static ssize_t ll_rw_offset_stats_seq_write(struct file *file, const char *buf,
struct ll_rw_process_info *offset_info = sbi->ll_rw_offset_info;
int value = 1, rc = 0;
+ if (len == 0)
+ return -EINVAL;
+
rc = lprocfs_write_helper(buf, len, &value);
- if (rc < 0 && (strcmp(buf, "disabled") == 0 ||
- strcmp(buf, "Disabled") == 0))
- value = 0;
+ if (rc < 0 && len < 16) {
+ char kernbuf[16];
+
+ if (copy_from_user(kernbuf, buf, len))
+ return -EFAULT;
+ kernbuf[len] = 0;
+
+ if (kernbuf[len - 1] == '\n')
+ kernbuf[len - 1] = 0;
+
+ if (strcmp(kernbuf, "disabled") == 0 ||
+ strcmp(kernbuf, "Disabled") == 0)
+ value = 0;
+ }
if (value == 0)
sbi->ll_rw_stats_on = 0;
diff --git a/drivers/staging/lustre/lustre/obdclass/linux/linux-module.c b/drivers/staging/lustre/lustre/obdclass/linux/linux-module.c
index dec1037..0334882 100644
--- a/drivers/staging/lustre/lustre/obdclass/linux/linux-module.c
+++ b/drivers/staging/lustre/lustre/obdclass/linux/linux-module.c
@@ -279,8 +279,15 @@ static ssize_t obd_proc_jobid_var_seq_write(struct file *file, const char *buffe
return -EINVAL;
memset(obd_jobid_var, 0, JOBSTATS_JOBID_VAR_MAX_LEN + 1);
+
+ /* This might leave the var invalid on error, which is probably fine.*/
+ if (copy_from_user(obd_jobid_var, buffer, count))
+ return -EFAULT;
+
/* Trim the trailing '\n' if any */
- memcpy(obd_jobid_var, buffer, count - (buffer[count - 1] == '\n'));
+ if (obd_jobid_var[count - 1] == '\n')
+ obd_jobid_var[count - 1] = 0;
+
return count;
}
LPROC_SEQ_FOPS(obd_proc_jobid_var);
diff --git a/drivers/staging/lustre/lustre/osc/lproc_osc.c b/drivers/staging/lustre/lustre/osc/lproc_osc.c
index 0b59fc1..358e32c 100644
--- a/drivers/staging/lustre/lustre/osc/lproc_osc.c
+++ b/drivers/staging/lustre/lustre/osc/lproc_osc.c
@@ -174,15 +174,25 @@ static int osc_cached_mb_seq_show(struct seq_file *m, void *v)
}
/* shrink the number of caching pages to a specific number */
-static ssize_t osc_cached_mb_seq_write(struct file *file, const char *buffer,
- size_t count, loff_t *off)
+static ssize_t osc_cached_mb_seq_write(struct file *file,
+ const char __user *buffer,
+ size_t count, loff_t *off)
{
struct obd_device *dev = ((struct seq_file *)file->private_data)->private;
struct client_obd *cli = &dev->u.cli;
int pages_number, mult, rc;
+ char kernbuf[128];
+
+ if (count >= sizeof(kernbuf))
+ return -EINVAL;
+
+ if (copy_from_user(kernbuf, buffer, count))
+ return -EFAULT;
+ kernbuf[count] = 0;
mult = 1 << (20 - PAGE_CACHE_SHIFT);
- buffer = lprocfs_find_named_value(buffer, "used_mb:", &count);
+ buffer += lprocfs_find_named_value(kernbuf, "used_mb:", &count) -
+ kernbuf;
rc = lprocfs_write_frac_helper(buffer, count, &pages_number, mult);
if (rc)
return rc;
--
1.8.5.3
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