From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Thu, 29 Jun 2023 15:28:46 +0000 (+0200)
Subject: 4.14-stable patches
X-Git-Tag: v6.4.1~29
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=168cd9125370a1fcb269231f22e5805b74062fb6;p=thirdparty%2Fkernel%2Fstable-queue.git

4.14-stable patches

added patches:
	fbdev-imsttfb-fix-use-after-free-bug-in-imsttfb_probe.patch
---

diff --git a/queue-4.14/fbdev-imsttfb-fix-use-after-free-bug-in-imsttfb_probe.patch b/queue-4.14/fbdev-imsttfb-fix-use-after-free-bug-in-imsttfb_probe.patch
new file mode 100644
index 00000000000..0fb5192e06f
--- /dev/null
+++ b/queue-4.14/fbdev-imsttfb-fix-use-after-free-bug-in-imsttfb_probe.patch
@@ -0,0 +1,85 @@
+From c75f5a55061091030a13fef71b9995b89bc86213 Mon Sep 17 00:00:00 2001
+From: Zheng Wang <zyytlz.wz@163.com>
+Date: Thu, 27 Apr 2023 11:08:41 +0800
+Subject: fbdev: imsttfb: Fix use after free bug in imsttfb_probe
+
+From: Zheng Wang <zyytlz.wz@163.com>
+
+commit c75f5a55061091030a13fef71b9995b89bc86213 upstream.
+
+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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/video/fbdev/imsttfb.c |   18 ++++++++++--------
+ 1 file changed, 10 insertions(+), 8 deletions(-)
+
+--- a/drivers/video/fbdev/imsttfb.c
++++ b/drivers/video/fbdev/imsttfb.c
+@@ -1348,7 +1348,7 @@ static 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;
+@@ -1420,7 +1420,7 @@ static void init_imstt(struct fb_info *i
+ 	    || !(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");
+@@ -1460,12 +1460,13 @@ static void init_imstt(struct fb_info *i
+ 	if (register_framebuffer(info) < 0) {
+ 		fb_dealloc_cmap(&info->cmap);
+ 		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)
+@@ -1474,7 +1475,8 @@ static int imsttfb_probe(struct pci_dev
+ 	struct imstt_par *par;
+ 	struct fb_info *info;
+ 	struct device_node *dp;
+-	
++	int ret;
++
+ 	dp = pci_device_to_OF_node(pdev);
+ 	if(dp)
+ 		printk(KERN_INFO "%s: OF name %s\n",__func__, dp->name);
+@@ -1525,10 +1527,10 @@ static int imsttfb_probe(struct pci_dev
+ 	par->cmap_regs_phys = addr + 0x840000;
+ 	par->cmap_regs = (__u8 *)ioremap(addr + 0x840000, 0x1000);
+ 	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;
+ }
+ 
+ static void imsttfb_remove(struct pci_dev *pdev)
diff --git a/queue-4.14/series b/queue-4.14/series
index 967f63b28ea..91cd0d25fb1 100644
--- a/queue-4.14/series
+++ b/queue-4.14/series
@@ -1,3 +1,4 @@
 gfs2-don-t-deref-jdesc-in-evict.patch
 x86-microcode-amd-load-late-on-both-threads-too.patch
 x86-smp-use-dedicated-cache-line-for-mwait_play_dead.patch
+fbdev-imsttfb-fix-use-after-free-bug-in-imsttfb_probe.patch