unimore/kernel-hacking-2024-linux-steffo
unimore/kernel-hacking-2024-linux-steffo
1
Fork 0
Code Pull requests 5 Wiki Activity

vt_ioctl: fix GIO_UNIMAP regression

Browse source 
In commit 5ba1278787, 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: 5ba1278787 ("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>
This commit is contained in:
Jiri Slaby 2020-10-26 06:54:19 +01:00 committed by Greg Kroah-Hartman
parent 82e61c3909
commit d546547903
1 changed files with 5 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

11
drivers/tty/vt/vt_ioctl.c
View file

@ -549,7 +549,7 @@ static int vt_io_fontreset(struct console_font_op *op)
}
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;
@ -557,9 +557,11 @@ 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 (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);
@ -639,10 +641,7 @@ static int vt_io_ioctl(struct vc_data *vc, unsigned int cmd, void __user *up,
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;