Commit cb34175d authored by Jeongjun Park's avatar Jeongjun Park Committed by Gu Bowen
Browse files

vt: prevent kernel-infoleak in con_font_get() 

stable inclusion
from stable-v6.6.58
commit dc2d5f02636c7587bdd6d1f60fc59c55860b00a4
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/IB0ENE
CVE: CVE-2024-50076

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=dc2d5f02636c7587bdd6d1f60fc59c55860b00a4



--------------------------------

commit f956052e00de211b5c9ebaa1958366c23f82ee9e upstream.

font.data may not initialize all memory spaces depending on the implementation
of vc->vc_sw->con_font_get. This may cause info-leak, so to prevent this, it
is safest to modify it to initialize the allocated memory space to 0, and it
generally does not affect the overall performance of the system.

Cc: stable@vger.kernel.org
Reported-by: default avatar <syzbot+955da2d57931604ee691@syzkaller.appspotmail.com>
Fixes: 05e2600c ("VT: Bump font size limitation to 64x128 pixels")
Signed-off-by: default avatarJeongjun Park <aha310510@gmail.com>
Link: https://lore.kernel.org/r/20241010174619.59662-1-aha310510@gmail.com


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: default avatarGu Bowen <gubowen5@huawei.com>
parent 04bcd1e6

drivers/tty/vt/vt.c

+1 −1
Original line number Diff line number Diff line
@@ -4550,7 +4550,7 @@ static int con_font_get(struct vc_data *vc, struct console_font_op *op) 
		return -EINVAL;



	if (op->data) {

		font.data = kvmalloc(max_font_size, GFP_KERNEL);

		font.data = kvzalloc(max_font_size, GFP_KERNEL);

		if (!font.data)

			return -ENOMEM;

	} else