[lustre-devel] [PATCH 37/49] lnet: libcfs: discard cfs_trace_copyin_string()
James Simmons
jsimmons at infradead.org
Wed Apr 14 21:02:29 PDT 2021
From: Mr NeilBrown <neilb at suse.de>
Instead of cfs_trace_copyin_string(), use memdup_user_nul().
This combines the allocation with the copyin, and nul-terminates.
The resulting code is a lot simpler.
WC-bug-id: https://jira.whamcloud.com/browse/LU-14428
Lustre-commit: 67af976c806994ce ("LU-14428 libcfs: discard cfs_trace_copyin_string()")
Signed-off-by: Mr NeilBrown <neilb at suse.de>
Reviewed-on: https://review.whamcloud.com/41490
Reviewed-by: James Simmons <jsimmons at infradead.org>
Reviewed-by: Arshad Hussain <arshad.hussain at aeoncomputing.com>
Reviewed-by: Oleg Drokin <green at whamcloud.com>
Signed-off-by: James Simmons <jsimmons at infradead.org>
---
include/linux/libcfs/libcfs_debug.h | 2 --
net/lnet/libcfs/module.c | 19 +++++-------
net/lnet/libcfs/tracefile.c | 59 +++++++------------------------------
net/lnet/libcfs/tracefile.h | 2 --
net/lnet/lnet/router_proc.c | 22 +++++++-------
5 files changed, 30 insertions(+), 74 deletions(-)
diff --git a/include/linux/libcfs/libcfs_debug.h b/include/linux/libcfs/libcfs_debug.h
index 99905f7..93eb752 100644
--- a/include/linux/libcfs/libcfs_debug.h
+++ b/include/linux/libcfs/libcfs_debug.h
@@ -209,8 +209,6 @@ int libcfs_debug_msg(struct libcfs_debug_msg_data *msgdata,
__printf(2, 3);
/* other external symbols that tracefile provides: */
-int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
- const char __user *usr_buffer, int usr_buffer_nob);
int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
const char *knl_buffer, char *append);
diff --git a/net/lnet/libcfs/module.c b/net/lnet/libcfs/module.c
index f9cc6df..93e9b9e 100644
--- a/net/lnet/libcfs/module.c
+++ b/net/lnet/libcfs/module.c
@@ -295,7 +295,7 @@ static int proc_dobitmasks(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp, loff_t *ppos)
{
const int tmpstrlen = 512;
- char *tmpstr;
+ char *tmpstr = NULL;
int rc;
size_t nob = *lenp;
loff_t pos = *ppos;
@@ -303,11 +303,10 @@ static int proc_dobitmasks(struct ctl_table *table, int write,
int is_subsys = (mask == &libcfs_subsystem_debug) ? 1 : 0;
int is_printk = (mask == &libcfs_printk) ? 1 : 0;
- tmpstr = kzalloc(tmpstrlen, GFP_KERNEL);
- if (!tmpstr)
- return -ENOMEM;
-
if (!write) {
+ tmpstr = kzalloc(tmpstrlen, GFP_KERNEL);
+ if (!tmpstr)
+ return -ENOMEM;
libcfs_debug_mask2str(tmpstr, tmpstrlen, *mask, is_subsys);
rc = strlen(tmpstr);
@@ -318,13 +317,11 @@ static int proc_dobitmasks(struct ctl_table *table, int write,
tmpstr + pos, "\n");
}
} else {
- rc = cfs_trace_copyin_string(tmpstr, tmpstrlen, buffer, nob);
- if (rc < 0) {
- kfree(tmpstr);
- return rc;
- }
+ tmpstr = memdup_user_nul(buffer, nob);
+ if (!tmpstr)
+ return -ENOMEM;
- rc = libcfs_debug_str2mask(mask, tmpstr, is_subsys);
+ rc = libcfs_debug_str2mask(mask, strim(tmpstr), is_subsys);
/* Always print LBUG/LASSERT to console, so keep this mask */
if (is_printk)
*mask |= D_EMERG;
diff --git a/net/lnet/libcfs/tracefile.c b/net/lnet/libcfs/tracefile.c
index e3a063f..731623b 100644
--- a/net/lnet/libcfs/tracefile.c
+++ b/net/lnet/libcfs/tracefile.c
@@ -920,34 +920,6 @@ void cfs_trace_flush_pages(void)
}
}
-int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
- const char __user *usr_buffer, int usr_buffer_nob)
-{
- int nob;
-
- if (usr_buffer_nob > knl_buffer_nob)
- return -EOVERFLOW;
-
- if (copy_from_user((void *)knl_buffer,
- usr_buffer, usr_buffer_nob))
- return -EFAULT;
-
- nob = strnlen(knl_buffer, usr_buffer_nob);
- while (--nob >= 0) /* strip trailing whitespace */
- if (!isspace(knl_buffer[nob]))
- break;
-
- if (nob < 0) /* empty string */
- return -EINVAL;
-
- if (nob == knl_buffer_nob) /* no space to terminate */
- return -EOVERFLOW;
-
- knl_buffer[nob + 1] = 0; /* terminate */
- return 0;
-}
-EXPORT_SYMBOL(cfs_trace_copyin_string);
-
int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
const char *knl_buffer, char *append)
{
@@ -977,26 +949,20 @@ int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
int cfs_trace_dump_debug_buffer_usrstr(void __user *usr_str, int usr_str_nob)
{
char *str;
+ char *path;
int rc;
- if (usr_str_nob >= 2 * PAGE_SIZE)
- return -EINVAL;
- str = kzalloc(usr_str_nob + 1, GFP_KERNEL);
+ str = memdup_user_nul(usr_str, usr_str_nob);
if (!str)
return -ENOMEM;
- rc = cfs_trace_copyin_string(str, usr_str_nob + 1,
- usr_str, usr_str_nob);
- if (rc)
- goto out;
-
- if (str[0] != '/') {
+ path = strim(str);
+ if (path[0] != '/')
rc = -EINVAL;
- goto out;
- }
- rc = cfs_tracefile_dump_all_pages(str);
-out:
+ else
+ rc = cfs_tracefile_dump_all_pages(str);
kfree(str);
+
return rc;
}
@@ -1045,18 +1011,13 @@ int cfs_trace_daemon_command_usrstr(void __user *usr_str, int usr_str_nob)
char *str;
int rc;
- if (usr_str_nob >= 2 * PAGE_SIZE)
- return -EINVAL;
- str = kzalloc(usr_str_nob + 1, GFP_KERNEL);
+ str = memdup_user_nul(usr_str, usr_str_nob);
if (!str)
return -ENOMEM;
- rc = cfs_trace_copyin_string(str, usr_str_nob + 1,
- usr_str, usr_str_nob);
- if (!rc)
- rc = cfs_trace_daemon_command(str);
-
+ rc = cfs_trace_daemon_command(str);
kfree(str);
+
return rc;
}
diff --git a/net/lnet/libcfs/tracefile.h b/net/lnet/libcfs/tracefile.h
index 5b90c1b..311ec8c 100644
--- a/net/lnet/libcfs/tracefile.h
+++ b/net/lnet/libcfs/tracefile.h
@@ -59,8 +59,6 @@
int cfs_tracefile_init(int max_pages);
void cfs_tracefile_exit(void);
-int cfs_trace_copyin_string(char *knl_buffer, int knl_buffer_nob,
- const char __user *usr_buffer, int usr_buffer_nob);
int cfs_trace_copyout_string(char __user *usr_buffer, int usr_buffer_nob,
const char *knl_str, char *append);
int cfs_trace_dump_debug_buffer_usrstr(void __user *usr_str, int usr_str_nob);
diff --git a/net/lnet/lnet/router_proc.c b/net/lnet/lnet/router_proc.c
index 623899e..25d172d 100644
--- a/net/lnet/lnet/router_proc.c
+++ b/net/lnet/lnet/router_proc.c
@@ -743,7 +743,7 @@ struct lnet_portal_rotors {
const char *pr_desc;
};
-static struct lnet_portal_rotors portal_rotors[] = {
+static struct lnet_portal_rotors portal_rotors[] = {
{
.pr_value = LNET_PTL_ROTOR_OFF,
.pr_name = "OFF",
@@ -783,11 +783,11 @@ static int proc_lnet_portal_rotor(struct ctl_table *table, int write,
int rc;
int i;
- buf = kmalloc(buf_len, GFP_KERNEL);
- if (!buf)
- return -ENOMEM;
-
if (!write) {
+ buf = kmalloc(buf_len, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
lnet_res_lock(0);
for (i = 0; portal_rotors[i].pr_value >= 0; i++) {
@@ -810,12 +810,14 @@ static int proc_lnet_portal_rotor(struct ctl_table *table, int write,
rc = cfs_trace_copyout_string(buffer, nob,
buf + pos, "\n");
}
- goto out;
+ kfree(buf);
+
+ return rc;
}
- rc = cfs_trace_copyin_string(buf, buf_len, buffer, nob);
- if (rc < 0)
- goto out;
+ buf = memdup_user_nul(buffer, nob);
+ if (!buf)
+ return -ENOMEM;
tmp = strim(buf);
@@ -830,8 +832,8 @@ static int proc_lnet_portal_rotor(struct ctl_table *table, int write,
}
}
lnet_res_unlock(0);
-out:
kfree(buf);
+
return rc;
}
--
1.8.3.1
More information about the lustre-devel
mailing list