From: Jiri Slaby jslaby@suse.cz
commit d54654790302ccaa72589380dce060d376ef8716 upstream.
In commit 5ba127878722, we shuffled with the check of 'perm'. But my brain somehow inverted the condition in 'do_unimap_ioctl' (I thought it is ||, not &&), so GIO_UNIMAP stopped working completely.
Move the 'perm' checks back to do_unimap_ioctl and do them right again. In fact, this reverts this part of code to the pre-5ba127878722 state. Except 'perm' is now a bool.
Fixes: 5ba127878722 ("vt_ioctl: move perm checks level up") Cc: stable@vger.kernel.org Reported-by: Fabian Vogt fvogt@suse.com Signed-off-by: Jiri Slaby jslaby@suse.cz Link: https://lore.kernel.org/r/20201026055419.30518-1-jslaby@suse.cz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/tty/vt/vt_ioctl.c | 11 +++++------ 1 file changed, 5 insertions(+), 6 deletions(-)
--- a/drivers/tty/vt/vt_ioctl.c +++ b/drivers/tty/vt/vt_ioctl.c @@ -550,7 +550,7 @@ static int vt_io_fontreset(struct consol }
static inline int do_unimap_ioctl(int cmd, struct unimapdesc __user *user_ud, - struct vc_data *vc) + bool perm, struct vc_data *vc) { struct unimapdesc tmp;
@@ -558,9 +558,11 @@ static inline int do_unimap_ioctl(int cm 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 (fg_console != vc->vc_num) + if (!perm && fg_console != vc->vc_num) return -EPERM; return con_get_unimap(vc, tmp.entry_ct, &(user_ud->entry_ct), tmp.entries); @@ -640,10 +642,7 @@ static int vt_io_ioctl(struct vc_data *v
case PIO_UNIMAP: case GIO_UNIMAP: - if (!perm) - return -EPERM; - - return do_unimap_ioctl(cmd, up, vc); + return do_unimap_ioctl(cmd, up, perm, vc);
default: return -ENOIOCTLCMD;