4.19-stable review patch. If anyone has any objections, please let me know.
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From: Dan Carpenter dan.carpenter@linaro.org
[ Upstream commit aba6ab57a910ad4b940c2024d15f2cdbf5b7f76b ]
I've re-written the error handling but the bug is that if init_imstt() fails we need to call iounmap(par->cmap_regs).
Fixes: c75f5a550610 ("fbdev: imsttfb: Fix use after free bug in imsttfb_probe") Signed-off-by: Dan Carpenter dan.carpenter@linaro.org Signed-off-by: Helge Deller deller@gmx.de Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/video/fbdev/imsttfb.c | 29 ++++++++++++++++------------- 1 file changed, 16 insertions(+), 13 deletions(-)
diff --git a/drivers/video/fbdev/imsttfb.c b/drivers/video/fbdev/imsttfb.c index 9a9018d143761..30ba79d3dbea4 100644 --- a/drivers/video/fbdev/imsttfb.c +++ b/drivers/video/fbdev/imsttfb.c @@ -1493,8 +1493,8 @@ static int imsttfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
if (!request_mem_region(addr, size, "imsttfb")) { printk(KERN_ERR "imsttfb: Can't reserve memory region\n"); - framebuffer_release(info); - return -ENODEV; + ret = -ENODEV; + goto release_info; }
switch (pdev->device) { @@ -1511,36 +1511,39 @@ static int imsttfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent) printk(KERN_INFO "imsttfb: Device 0x%x unknown, " "contact maintainer.\n", pdev->device); ret = -ENODEV; - goto error; + goto release_mem_region; }
info->fix.smem_start = addr; info->screen_base = (__u8 *)ioremap(addr, par->ramdac == IBM ? 0x400000 : 0x800000); if (!info->screen_base) - goto error; + goto release_mem_region; info->fix.mmio_start = addr + 0x800000; par->dc_regs = ioremap(addr + 0x800000, 0x1000); if (!par->dc_regs) - goto error; + goto unmap_screen_base; par->cmap_regs_phys = addr + 0x840000; par->cmap_regs = (__u8 *)ioremap(addr + 0x840000, 0x1000); if (!par->cmap_regs) - goto error; + goto unmap_dc_regs; info->pseudo_palette = par->palette; ret = init_imstt(info); if (ret) - goto error; + goto unmap_cmap_regs;
pci_set_drvdata(pdev, info); - return ret; + return 0;
-error: - if (par->dc_regs) - iounmap(par->dc_regs); - if (info->screen_base) - iounmap(info->screen_base); +unmap_cmap_regs: + iounmap(par->cmap_regs); +unmap_dc_regs: + iounmap(par->dc_regs); +unmap_screen_base: + iounmap(info->screen_base); +release_mem_region: release_mem_region(addr, size); +release_info: framebuffer_release(info); return ret; }