vt_ioctl: move perm checks level up

Synchronize with others and check perm directly in vt_k_ioctl.
We do not need to pass perm to do_fontx_ioctl and do_unimap_ioctl then.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20200615074910.19267-38-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Jiri Slaby 2020-06-15 09:49:10 +02:00 committed by Greg Kroah-Hartman
parent a4c53c830b
commit 5ba1278787

View File

@ -486,7 +486,7 @@ static int vt_k_ioctl(struct tty_struct *tty, unsigned int cmd,
}
static inline int do_fontx_ioctl(int cmd,
struct consolefontdesc __user *user_cfd, int perm,
struct consolefontdesc __user *user_cfd,
struct console_font_op *op)
{
struct consolefontdesc cfdarg;
@ -497,8 +497,6 @@ static inline int do_fontx_ioctl(int cmd,
switch (cmd) {
case PIO_FONTX:
if (!perm)
return -EPERM;
op->op = KD_FONT_OP_SET;
op->flags = KD_FONT_FLAG_OLD;
op->width = 8;
@ -552,7 +550,7 @@ static int vt_io_fontreset(struct console_font_op *op)
}
static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
int perm, struct vc_data *vc)
struct vc_data *vc)
{
struct unimapdesc tmp;
@ -560,11 +558,9 @@ static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud,
return -EFAULT;
switch (cmd) {
case PIO_UNIMAP:
if (!perm)
return -EPERM;
return con_set_unimap(vc, tmp.entry_ct, tmp.entries);
case GIO_UNIMAP:
if (!perm && fg_console != vc->vc_num)
if (fg_console != vc->vc_num)
return -EPERM;
return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct),
tmp.entries);
@ -607,8 +603,12 @@ static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
return con_get_cmap(up);
case PIO_FONTX:
if (!perm)
return -EPERM;
fallthrough;
case GIO_FONTX:
return do_fontx_ioctl(cmd, up, perm, &op);
return do_fontx_ioctl(cmd, up, &op);
case PIO_FONTRESET:
if (!perm)
@ -640,7 +640,10 @@ static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
case PIO_UNIMAP:
case GIO_UNIMAP:
return do_unimap_ioctl(cmd, up, perm, vc);
if (!perm)
return -EPERM;
return do_unimap_ioctl(cmd, up, vc);
default:
return -ENOIOCTLCMD;