[PATCH v2 1/6] ice: ensure the copied buf is NUL terminated

[Bui Quang Minh]

Currently, we allocate a count-sized kernel buffer and copy count bytes
from userspace to that buffer. Later, we use sscanf on this buffer but we
don't ensure that the string is terminated inside the buffer, this can lead
to OOB read when using sscanf. Fix this issue by using memdup_user_nul
instead of memdup_user.

Fixes: 96a9a9341cda ("ice: configure FW logging")
Fixes: 73671c3162c8 ("ice: enable FW logging")
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@xxxxxxxxx>
Signed-off-by: Bui Quang Minh <minhquangbui99@xxxxxxxxx>
---
 drivers/net/ethernet/intel/ice/ice_debugfs.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_debugfs.c b/drivers/net/ethernet/intel/ice/ice_debugfs.c
index d252d98218d0..9fc0fd95a13d 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);
 

-- 
2.34.1