From: Matthew Daley Date: Mon, 28 Apr 2014 07:05:20 +0000 (+1200) Subject: floppy: ignore kernel-only members in FDRAWCMD ioctl input X-Git-Tag: v2.6.32.62~2 X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f76b441b9d5879587f53525933d27b16217ca78c;p=linux floppy: ignore kernel-only members in FDRAWCMD ioctl input Always clear out these floppy_raw_cmd struct members after copying the entire structure from userspace so that the in-kernel version is always valid and never left in an interdeterminate state. Signed-off-by: Matthew Daley Signed-off-by: Linus Torvalds (cherry picked from commit ef87dbe7614341c2e7bfe8d32fcb7028cc97442c) [wt: be careful in 2.6.32 we still have the ugly macros everywhere] Signed-off-by: Willy Tarreau --- diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index 5c01f747571b..19d45e6c2b9b 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -3209,9 +3209,12 @@ static inline int raw_cmd_copyin(int cmd, char __user *param, if (!ptr) return -ENOMEM; *rcmd = ptr; - COPYIN(*ptr); + ret = copy_from_user(ptr, (void __user *)param, sizeof(*ptr)); ptr->next = NULL; ptr->buffer_length = 0; + ptr->kernel_data = NULL; + if (ret) + return -EFAULT; param += sizeof(struct floppy_raw_cmd); if (ptr->cmd_count > 33) /* the command may now also take up the space