From: Thomas Zimmermann <tzimmermann@suse.de> stable inclusion from stable-v5.10.245 commit b451631b0b02246120cf8cf01f8796e3e9c4e4ec category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/ID22A7 CVE: CVE-2025-39967 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 9b2f5ef00e852f8e8902a4d4f73aeedc60220c12 upstream. Commit 1a194e6c8e1e ("fbcon: fix integer overflow in fbcon_do_set_font") introduced an out-of-bounds access by storing data and allocation sizes in the same variable. Restore the old size calculation and use the new variable 'alloc_size' for the allocation. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Fixes: 1a194e6c8e1e ("fbcon: fix integer overflow in fbcon_do_set_font") Reported-by: Jani Nikula <jani.nikula@linux.intel.com> Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/15020 Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6201 Cc: Samasth Norway Ananda <samasth.norway.ananda@oracle.com> Cc: Thomas Zimmermann <tzimmermann@suse.de> Cc: George Kennedy <george.kennedy@oracle.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Simona Vetter <simona@ffwll.ch> Cc: Helge Deller <deller@gmx.de> Cc: "Ville Syrjälä" <ville.syrjala@linux.intel.com> Cc: Sam Ravnborg <sam@ravnborg.org> Cc: Qianqiang Liu <qianqiang.liu@163.com> Cc: Shixiong Ou <oushixiong@kylinos.cn> Cc: Kees Cook <kees@kernel.org> Cc: <stable@vger.kernel.org> # v5.9+ Cc: Zsolt Kajtar <soci@c64.rulez.org> Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com> Reviewed-by: Qianqiang Liu <qianqiang.liu@163.com> Link: https://lore.kernel.org/r/20250922134619.257684-1-tzimmermann@suse.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Zicheng Qu <quzicheng@huawei.com> --- drivers/video/fbdev/core/fbcon.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c index 15d51e1baf74..3aaf0053c9fc 100644 --- a/drivers/video/fbdev/core/fbcon.c +++ b/drivers/video/fbdev/core/fbcon.c @@ -2520,7 +2520,7 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, unsigned charcount = font->charcount; int w = font->width; int h = font->height; - int size; + int size, alloc_size; int i, csum; u8 *new_data, *data = font->data; int pitch = PITCH(font->width); @@ -2553,10 +2553,10 @@ static int fbcon_set_font(struct vc_data *vc, struct console_font *font, return -EINVAL; /* Check for overflow in allocation size calculation */ - if (check_add_overflow(FONT_EXTRA_WORDS * sizeof(int), size, &size)) + if (check_add_overflow(FONT_EXTRA_WORDS * sizeof(int), size, &alloc_size)) return -EINVAL; - new_data = kmalloc(size, GFP_USER); + new_data = kmalloc(alloc_size, GFP_USER); if (!new_data) return -ENOMEM; -- 2.34.1