[ 143/143] floppy: dont write kernel-only members to FDRAWCMD ioctl output

Willy Tarreau
2014-05-12T01:43:54Z

From: Matthew Daley <mattd@bugfuzz.com>

Do not leak kernel-only floppy_raw_cmd structure members to userspace.
This includes the linked-list pointer and the pointer to the allocated
DMA space.

Signed-off-by: Matthew Daley <mattd@bugfuzz.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit 2145e15e0557a01b9195d1c7199a1b92cb9be81f)
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
drivers/block/floppy.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 19d45e6..f959aad 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -3162,7 +3162,12 @@ static inline int raw_cmd_copyout(int cmd, char __user *param,
int ret;

while (ptr) {
- COPYOUT(*ptr);
+ struct floppy_raw_cmd cmd = *ptr;
+ cmd.next = NULL;
+ cmd.kernel_data = NULL;
+ ret = copy_to_user((void __user *)param, &cmd, sizeof(cmd));
+ if (ret)
+ return -EFAULT;
param += sizeof(struct floppy_raw_cmd);
if ((ptr->flags & FD_RAW_READ) && ptr->buffer_length) {
if (ptr->length >= 0
--
1.7.12.2.21.g234cd45.dirty