From: Jakob Koschel Date: Thu, 27 Jan 2022 14:44:05 +0000 (+0100) Subject: vt_ioctl: add array_index_nospec to VT_ACTIVATE X-Git-Tag: v4.19.230~15 X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=482e76aa0d00a42d976f23f63825903fd102b93c;p=users%2Fdwmw2%2Flinux.git vt_ioctl: add array_index_nospec to VT_ACTIVATE commit 28cb138f559f8c1a1395f5564f86b8bbee83631b upstream. in vt_setactivate an almost identical code path has been patched with array_index_nospec. In the VT_ACTIVATE path the user input is from a system call argument instead of a usercopy. For consistency both code paths should have the same mitigations applied. Kasper Acknowledgements: Jakob Koschel, Brian Johannesmeyer, Kaveh Razavi, Herbert Bos, Cristiano Giuffrida from the VUSec group at VU Amsterdam. Co-developed-by: Brian Johannesmeyer Signed-off-by: Brian Johannesmeyer Signed-off-by: Jakob Koschel Link: https://lore.kernel.org/r/20220127144406.3589293-2-jakobkoschel@gmail.com Cc: stable Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/tty/vt/vt_ioctl.c b/drivers/tty/vt/vt_ioctl.c index 5b162d0870390..78ae1f0908fd5 100644 --- a/drivers/tty/vt/vt_ioctl.c +++ b/drivers/tty/vt/vt_ioctl.c @@ -691,6 +691,7 @@ int vt_ioctl(struct tty_struct *tty, ret = -ENXIO; else { arg--; + arg = array_index_nospec(arg, MAX_NR_CONSOLES); console_lock(); ret = vc_allocate(arg); console_unlock();