[PATCH AUTOSEL 5.15 07/11] fbdev: imsttfb: Fix use after free bug in imsttfb_probe

[PATCH AUTOSEL 5.15 07/11] fbdev: imsttfb: Fix use after free bug in imsttfb_probe

[Sasha Levin]

From: Zheng Wang <zyytlz.wz@163.com>

[ Upstream commit c75f5a55061091030a13fef71b9995b89bc86213 ]

A use-after-free bug may occur if init_imstt invokes framebuffer_release
and free the info ptr. The caller, imsttfb_probe didn't notice that and
still keep the ptr as private data in pdev.

If we remove the driver which will call imsttfb_remove to make cleanup,
UAF happens.

Fix it by return error code if bad case happens in init_imstt.

Signed-off-by: Zheng Wang <zyytlz.wz@163.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/imsttfb.c | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

diff --git a/drivers/video/fbdev/imsttfb.c b/drivers/video/fbdev/imsttfb.c
index 16f272a508112..1b2fb8ed76237 100644
--- a/drivers/video/fbdev/imsttfb.c
+++ b/drivers/video/fbdev/imsttfb.c
@@ -1346,7 +1346,7 @@ static const struct fb_ops imsttfb_ops = {
 	.fb_ioctl 	= imsttfb_ioctl,
 };
 
-static void init_imstt(struct fb_info *info)
+static int init_imstt(struct fb_info *info)
 {
 	struct imstt_par *par = info->par;
 	__u32 i, tmp, *ip, *end;
@@ -1419,7 +1419,7 @@ static void init_imstt(struct fb_info *info)
 	    || !(compute_imstt_regvals(par, info->var.xres, info->var.yres))) {
 		printk("imsttfb: %ux%ux%u not supported\n", info->var.xres, info->var.yres, info->var.bits_per_pixel);
 		framebuffer_release(info);
-		return;
+		return -ENODEV;
 	}
 
 	sprintf(info->fix.id, "IMS TT (%s)", par->ramdac == IBM ? "IBM" : "TVP");
@@ -1455,12 +1455,13 @@ static void init_imstt(struct fb_info *info)
 
 	if (register_framebuffer(info) < 0) {
 		framebuffer_release(info);
-		return;
+		return -ENODEV;
 	}
 
 	tmp = (read_reg_le32(par->dc_regs, SSTATUS) & 0x0f00) >> 8;
 	fb_info(info, "%s frame buffer; %uMB vram; chip version %u\n",
 		info->fix.id, info->fix.smem_len >> 20, tmp);
+	return 0;
 }
 
 static int imsttfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
@@ -1523,10 +1524,10 @@ static int imsttfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 	if (!par->cmap_regs)
 		goto error;
 	info->pseudo_palette = par->palette;
-	init_imstt(info);
-
-	pci_set_drvdata(pdev, info);
-	return 0;
+	ret = init_imstt(info);
+	if (!ret)
+		pci_set_drvdata(pdev, info);
+	return ret;
 
 error:
 	if (par->dc_regs)
-- 
2.39.2

[PATCH AUTOSEL 5.15 08/11] fbdev: modedb: Add 1920x1080 at 60 Hz video mode

[Sasha Levin]

From: Helge Deller <deller@gmx.de>

[ Upstream commit c8902258b2b8ecaa1b8d88c312853c5b14c2553d ]

Add typical resolution for Full-HD monitors.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/core/modedb.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/video/fbdev/core/modedb.c b/drivers/video/fbdev/core/modedb.c
index 6473e0dfe1464..e78ec7f728463 100644
--- a/drivers/video/fbdev/core/modedb.c
+++ b/drivers/video/fbdev/core/modedb.c
@@ -257,6 +257,11 @@ static const struct fb_videomode modedb[] = {
 	{ NULL, 72, 480, 300, 33386, 40, 24, 11, 19, 80, 3, 0,
 		FB_VMODE_DOUBLE },
 
+	/* 1920x1080 @ 60 Hz, 67.3 kHz hsync */
+	{ NULL, 60, 1920, 1080, 6734, 148, 88, 36, 4, 44, 5, 0,
+		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
+		FB_VMODE_NONINTERLACED },
+
 	/* 1920x1200 @ 60 Hz, 74.5 Khz hsync */
 	{ NULL, 60, 1920, 1200, 5177, 128, 336, 1, 38, 208, 3,
 		FB_SYNC_HOR_HIGH_ACT | FB_SYNC_VERT_HIGH_ACT,
-- 
2.39.2

[PATCH AUTOSEL 5.15 09/11] fbdev: stifb: Fix info entry in sti_struct on error path

[Sasha Levin]

From: Helge Deller <deller@gmx.de>

[ Upstream commit 0bdf1ad8d10bd4e50a8b1a2c53d15984165f7fea ]

Minor fix to reset the info field to NULL in case of error.

Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/video/fbdev/stifb.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/video/fbdev/stifb.c b/drivers/video/fbdev/stifb.c
index ef8a4c5fc6875..63f51783352dc 100644
--- a/drivers/video/fbdev/stifb.c
+++ b/drivers/video/fbdev/stifb.c
@@ -1413,6 +1413,7 @@ static int __init stifb_init_fb(struct sti_struct *sti, int bpp_pref)
 	iounmap(info->screen_base);
 out_err0:
 	kfree(fb);
+	sti->info = NULL;
 	return -ENXIO;
 }
 
-- 
2.39.2