Merge branch 'ensure-the-copied-buf-is-nul-terminated'

Bui Quang Minh says:

====================
Ensure the copied buf is NUL terminated (part)

I found that some drivers contains an out-of-bound read pattern like this

	kern_buf = memdup_user(user_buf, count);
	...
	sscanf(kern_buf, ...);

The sscanf can be replaced by some other string-related functions. This
pattern can lead to out-of-bound read of kern_buf in string-related
functions.

This series fix the above issue by replacing memdup_user with
memdup_user_nul.

v1: https://lore.kernel.org/r/20240422-fix-oob-read-v1-0-e02854c30174@gmail.com
====================

Link: https://lore.kernel.org/r/20240424-fix-oob-read-v2-0-f1f1b53a10f4@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

3 files changed, 7 insertions, 9 deletions

diff --git a/drivers/net/ethernet/brocade/bna/bnad_debugfs.c b/drivers/net/ethernet/brocade/bna/bnad_debugfs.c
index 7246e13dd559fc..97291bfbeea589 100644
--- a/drivers/net/ethernet/brocade/bna/bnad_debugfs.c
+++ b/drivers/net/ethernet/brocade/bna/bnad_debugfs.c
@@ -312,7 +312,7 @@ bnad_debugfs_write_regrd(struct file *file, const char __user *buf,
 	void *kern_buf;
 
 	/* Copy the user space buf */
-	kern_buf = memdup_user(buf, nbytes);
+	kern_buf = memdup_user_nul(buf, nbytes);
 	if (IS_ERR(kern_buf))
 		return PTR_ERR(kern_buf);
 
@@ -372,7 +372,7 @@ bnad_debugfs_write_regwr(struct file *file, const char __user *buf,
 	void *kern_buf;
 
 	/* Copy the user space buf */
-	kern_buf = memdup_user(buf, nbytes);
+	kern_buf = memdup_user_nul(buf, nbytes);
 	if (IS_ERR(kern_buf))
 		return PTR_ERR(kern_buf);
 
diff --git a/drivers/net/ethernet/intel/ice/ice_debugfs.c b/drivers/net/ethernet/intel/ice/ice_debugfs.c
index d252d98218d084..9fc0fd95a13d8f 100644
--- a/drivers/net/ethernet/intel/ice/ice_debugfs.c
+++ b/drivers/net/ethernet/intel/ice/ice_debugfs.c
@@ -171,7 +171,7 @@ ice_debugfs_module_write(struct file *filp, const char __user *buf,
 	if (*ppos != 0 || count > 8)
 		return -EINVAL;
 
-	cmd_buf = memdup_user(buf, count);
+	cmd_buf = memdup_user_nul(buf, count);
 	if (IS_ERR(cmd_buf))
 		return PTR_ERR(cmd_buf);
 
@@ -257,7 +257,7 @@ ice_debugfs_nr_messages_write(struct file *filp, const char __user *buf,
 	if (*ppos != 0 || count > 4)
 		return -EINVAL;
 
-	cmd_buf = memdup_user(buf, count);
+	cmd_buf = memdup_user_nul(buf, count);
 	if (IS_ERR(cmd_buf))
 		return PTR_ERR(cmd_buf);
 
@@ -332,7 +332,7 @@ ice_debugfs_enable_write(struct file *filp, const char __user *buf,
 	if (*ppos != 0 || count > 2)
 		return -EINVAL;
 
-	cmd_buf = memdup_user(buf, count);
+	cmd_buf = memdup_user_nul(buf, count);
 	if (IS_ERR(cmd_buf))
 		return PTR_ERR(cmd_buf);
 
@@ -428,7 +428,7 @@ ice_debugfs_log_size_write(struct file *filp, const char __user *buf,
 	if (*ppos != 0 || count > 5)
 		return -EINVAL;
 
-	cmd_buf = memdup_user(buf, count);
+	cmd_buf = memdup_user_nul(buf, count);
 	if (IS_ERR(cmd_buf))
 		return PTR_ERR(cmd_buf);
 
diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
index 2500f5ba4f5a42..881d704644fbee 100644
--- a/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
+++ b/drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
@@ -999,12 +999,10 @@ static ssize_t rvu_dbg_qsize_write(struct file *filp,
 	u16 pcifunc;
 	int ret, lf;
 
-	cmd_buf = memdup_user(buffer, count + 1);
+	cmd_buf = memdup_user_nul(buffer, count);
 	if (IS_ERR(cmd_buf))
 		return -ENOMEM;
 
-	cmd_buf[count] = '\0';
-
 	cmd_buf_tmp = strchr(cmd_buf, '\n');
 	if (cmd_buf_tmp) {
 		*cmd_buf_tmp = '\0';