[PATCH] lib: fix callers of strtobool to use char array
From: Kees Cook
Date: Wed Jan 27 2016 - 19:46:28 EST
Some callers of strtobool were passing a pointer to unterminated strings.
This fixes the issue and consolidates some logic in cifs.
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Amitkumar Karwar <akarwar@xxxxxxxxxxx>
Cc: Nishant Sarmukadam <nishants@xxxxxxxxxxx>
Cc: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Cc: Steve French <sfrench@xxxxxxxxx>
Cc: linux-cifs@xxxxxxxxxxxxxxx
---
This is preparation for adding "on"/"off" support to strtobool(), and I
want to make sure the solution isn't upsetting to the two callers. :)
---
drivers/net/wireless/marvell/mwifiex/debugfs.c | 6 +-
fs/cifs/cifs_debug.c | 78 ++++++++++++--------------
fs/cifs/cifs_debug.h | 2 +-
fs/cifs/cifsfs.c | 6 +-
fs/cifs/cifsglob.h | 4 +-
5 files changed, 44 insertions(+), 52 deletions(-)
diff --git a/drivers/net/wireless/marvell/mwifiex/debugfs.c b/drivers/net/wireless/marvell/mwifiex/debugfs.c
index 0b9c580af988..76af60899c69 100644
--- a/drivers/net/wireless/marvell/mwifiex/debugfs.c
+++ b/drivers/net/wireless/marvell/mwifiex/debugfs.c
@@ -880,13 +880,13 @@ mwifiex_reset_write(struct file *file,
{
struct mwifiex_private *priv = file->private_data;
struct mwifiex_adapter *adapter = priv->adapter;
- char cmd;
+ char cmd[2] = { '\0' };
bool result;
- if (copy_from_user(&cmd, ubuf, sizeof(cmd)))
+ if (copy_from_user(cmd, ubuf, sizeof(char)))
return -EFAULT;
- if (strtobool(&cmd, &result))
+ if (strtobool(cmd, &result))
return -EINVAL;
if (!result)
diff --git a/fs/cifs/cifs_debug.c b/fs/cifs/cifs_debug.c
index 50b268483302..cafe464fa1b7 100644
--- a/fs/cifs/cifs_debug.c
+++ b/fs/cifs/cifs_debug.c
@@ -251,11 +251,29 @@ static const struct file_operations cifs_debug_data_proc_fops = {
.release = single_release,
};
+static int get_user_bool(const char __user *buffer, bool *store)
+{
+ char c[2] = { '\0' };
+ bool bv;
+ int rc;
+
+ rc = get_user(c[0], buffer);
+ if (rc)
+ return rc;
+
+ rc = strtobool(c, &bv);
+ if (rc)
+ return rc;
+
+ *store = bv;
+
+ return 0;
+}
+
#ifdef CONFIG_CIFS_STATS
static ssize_t cifs_stats_proc_write(struct file *file,
const char __user *buffer, size_t count, loff_t *ppos)
{
- char c;
bool bv;
int rc;
struct list_head *tmp1, *tmp2, *tmp3;
@@ -263,11 +281,8 @@ static ssize_t cifs_stats_proc_write(struct file *file,
struct cifs_ses *ses;
struct cifs_tcon *tcon;
- rc = get_user(c, buffer);
- if (rc)
- return rc;
-
- if (strtobool(&c, &bv) == 0) {
+ rc = get_user_bool(buffer, &bv);
+ if (rc == 0) {
#ifdef CONFIG_CIFS_STATS2
atomic_set(&totBufAllocCount, 0);
atomic_set(&totSmBufAllocCount, 0);
@@ -290,7 +305,8 @@ static ssize_t cifs_stats_proc_write(struct file *file,
}
}
spin_unlock(&cifs_tcp_ses_lock);
- }
+ } else
+ return rc;
return count;
}
@@ -433,17 +449,17 @@ static int cifsFYI_proc_open(struct inode *inode, struct file *file)
static ssize_t cifsFYI_proc_write(struct file *file, const char __user *buffer,
size_t count, loff_t *ppos)
{
- char c;
+ char c[2] = { '\0' };
bool bv;
int rc;
- rc = get_user(c, buffer);
+ rc = get_user(c[0], buffer);
if (rc)
return rc;
- if (strtobool(&c, &bv) == 0)
+ if (strtobool(c, &bv) == 0)
cifsFYI = bv;
- else if ((c > '1') && (c <= '9'))
- cifsFYI = (int) (c - '0'); /* see cifs_debug.h for meanings */
+ else if ((c[0] > '1') && (c[0] <= '9'))
+ cifsFYI = (int) (c[0] - '0'); /* see cifs_debug.h for meanings */
return count;
}
@@ -471,20 +487,12 @@ static int cifs_linux_ext_proc_open(struct inode *inode, struct file *file)
static ssize_t cifs_linux_ext_proc_write(struct file *file,
const char __user *buffer, size_t count, loff_t *ppos)
{
- char c;
- bool bv;
int rc;
- rc = get_user(c, buffer);
+ rc = get_user_bool(buffer, &linuxExtEnabled);
if (rc)
return rc;
- rc = strtobool(&c, &bv);
- if (rc)
- return rc;
-
- linuxExtEnabled = bv;
-
return count;
}
@@ -511,20 +519,12 @@ static int cifs_lookup_cache_proc_open(struct inode *inode, struct file *file)
static ssize_t cifs_lookup_cache_proc_write(struct file *file,
const char __user *buffer, size_t count, loff_t *ppos)
{
- char c;
- bool bv;
int rc;
- rc = get_user(c, buffer);
+ rc = get_user_bool(buffer, &lookupCacheEnabled);
if (rc)
return rc;
- rc = strtobool(&c, &bv);
- if (rc)
- return rc;
-
- lookupCacheEnabled = bv;
-
return count;
}
@@ -551,20 +551,12 @@ static int traceSMB_proc_open(struct inode *inode, struct file *file)
static ssize_t traceSMB_proc_write(struct file *file, const char __user *buffer,
size_t count, loff_t *ppos)
{
- char c;
- bool bv;
int rc;
- rc = get_user(c, buffer);
+ rc = get_user_bool(buffer, &traceSMB);
if (rc)
return rc;
- rc = strtobool(&c, &bv);
- if (rc)
- return rc;
-
- traceSMB = bv;
-
return count;
}
@@ -622,7 +614,7 @@ static ssize_t cifs_security_flags_proc_write(struct file *file,
int rc;
unsigned int flags;
char flags_string[12];
- char c;
+ char c[2] = { '\0' };
bool bv;
if ((count < 1) || (count > 11))
@@ -635,11 +627,11 @@ static ssize_t cifs_security_flags_proc_write(struct file *file,
if (count < 3) {
/* single char or single char followed by null */
- c = flags_string[0];
- if (strtobool(&c, &bv) == 0) {
+ c[0] = flags_string[0];
+ if (strtobool(c, &bv) == 0) {
global_secflags = bv ? CIFSSEC_MAX : CIFSSEC_DEF;
return count;
- } else if (!isdigit(c)) {
+ } else if (!isdigit(c[0])) {
cifs_dbg(VFS, "Invalid SecurityFlags: %s\n",
flags_string);
return -EINVAL;
diff --git a/fs/cifs/cifs_debug.h b/fs/cifs/cifs_debug.h
index 66cf0f9fff89..c611ca2339d7 100644
--- a/fs/cifs/cifs_debug.h
+++ b/fs/cifs/cifs_debug.h
@@ -25,7 +25,7 @@
void cifs_dump_mem(char *label, void *data, int length);
void cifs_dump_detail(void *);
void cifs_dump_mids(struct TCP_Server_Info *);
-extern int traceSMB; /* flag which enables the function below */
+extern bool traceSMB; /* flag which enables the function below */
void dump_smb(void *, int);
#define CIFS_INFO 0x01
#define CIFS_RC 0x02
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index c48ca13673e3..931b446f2a44 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -54,10 +54,10 @@
#endif
int cifsFYI = 0;
-int traceSMB = 0;
+bool traceSMB;
bool enable_oplocks = true;
-unsigned int linuxExtEnabled = 1;
-unsigned int lookupCacheEnabled = 1;
+bool linuxExtEnabled = true;
+bool lookupCacheEnabled = true;
unsigned int global_secflags = CIFSSEC_DEF;
/* unsigned int ntlmv2_support = 0; */
unsigned int sign_CIFS_PDUs = 1;
diff --git a/fs/cifs/cifsglob.h b/fs/cifs/cifsglob.h
index a25b2513f146..d21da9f05bae 100644
--- a/fs/cifs/cifsglob.h
+++ b/fs/cifs/cifsglob.h
@@ -1596,11 +1596,11 @@ GLOBAL_EXTERN atomic_t midCount;
/* Misc globals */
GLOBAL_EXTERN bool enable_oplocks; /* enable or disable oplocks */
-GLOBAL_EXTERN unsigned int lookupCacheEnabled;
+GLOBAL_EXTERN bool lookupCacheEnabled;
GLOBAL_EXTERN unsigned int global_secflags; /* if on, session setup sent
with more secure ntlmssp2 challenge/resp */
GLOBAL_EXTERN unsigned int sign_CIFS_PDUs; /* enable smb packet signing */
-GLOBAL_EXTERN unsigned int linuxExtEnabled;/*enable Linux/Unix CIFS extensions*/
+GLOBAL_EXTERN bool linuxExtEnabled;/*enable Linux/Unix CIFS extensions*/
GLOBAL_EXTERN unsigned int CIFSMaxBufSize; /* max size not including hdr */
GLOBAL_EXTERN unsigned int cifs_min_rcv; /* min size of big ntwrk buf pool */
GLOBAL_EXTERN unsigned int cifs_min_small; /* min size of small buf pool */
--
2.6.3
--
Kees Cook
Chrome OS & Brillo Security