4.14-stable review patch. If anyone has any objections, please let me know.
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[ Upstream commit a5399db139cb3ad9b8502d8b1bd02da9ce0b9df0 ]
There is no clipping on the x or y axis for logos larger that the framebuffer size. Therefore: a logo bigger than screen size leads to invalid memory access:
[ 1.254664] Backtrace: [ 1.254728] [<c02714e0>] (cfb_imageblit) from [<c026184c>] (fb_show_logo+0x620/0x684) [ 1.254763] r10:00000003 r9:00027fd8 r8:c6a40000 r7:c6a36e50 r6:00000000 r5:c06b81e4 [ 1.254774] r4:c6a3e800 [ 1.254810] [<c026122c>] (fb_show_logo) from [<c026c1e4>] (fbcon_switch+0x3fc/0x46c) [ 1.254842] r10:c6a3e824 r9:c6a3e800 r8:00000000 r7:c6a0c000 r6:c070b014 r5:c6a3e800 [ 1.254852] r4:c6808c00 [ 1.254889] [<c026bde8>] (fbcon_switch) from [<c029c8f8>] (redraw_screen+0xf0/0x1e8) [ 1.254918] r10:00000000 r9:00000000 r8:00000000 r7:00000000 r6:c070d5a0 r5:00000080 [ 1.254928] r4:c6808c00 [ 1.254961] [<c029c808>] (redraw_screen) from [<c029d264>] (do_bind_con_driver+0x194/0x2e4) [ 1.254991] r9:00000000 r8:00000000 r7:00000014 r6:c070d5a0 r5:c070d5a0 r4:c070d5a0
So prevent displaying a logo bigger than screen size and avoid invalid memory access.
Signed-off-by: Manfred Schlaegl manfred.schlaegl@ginzinger.com Signed-off-by: Martin Kepplinger martin.kepplinger@ginzinger.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Signed-off-by: Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/video/fbdev/core/fbmem.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/video/fbdev/core/fbmem.c b/drivers/video/fbdev/core/fbmem.c index 302cce7185e3..83961a22bef1 100644 --- a/drivers/video/fbdev/core/fbmem.c +++ b/drivers/video/fbdev/core/fbmem.c @@ -427,6 +427,9 @@ static void fb_do_show_logo(struct fb_info *info, struct fb_image *image, { unsigned int x;
+ if (image->width > info->var.xres || image->height > info->var.yres) + return; + if (rotate == FB_ROTATE_UR) { for (x = 0; x < num && image->dx + image->width <= info->var.xres;