w100fb_probe() did not reset the global state to its initial state. This can result in invocation of iounmap() even when there was not the appropriate successful call of ioremap(). For instance, this may be the case if first probe fails after two successful ioremap() while second probe fails when first ioremap() fails. The similar issue is with w100fb_remove(). The patch fixes both bugs.
Found by Linux Driver Verification project (linuxtesting.org).
Signed-off-by: Evgeny Novikov novikov@ispras.ru Co-developed-by: Kirill Shilimanov kirill.shilimanov@huawei.com Signed-off-by: Kirill Shilimanov kirill.shilimanov@huawei.com --- drivers/video/fbdev/w100fb.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-)
diff --git a/drivers/video/fbdev/w100fb.c b/drivers/video/fbdev/w100fb.c index d96ab28f8ce4..4e641a780726 100644 --- a/drivers/video/fbdev/w100fb.c +++ b/drivers/video/fbdev/w100fb.c @@ -770,12 +770,18 @@ static int w100fb_probe(struct platform_device *pdev) fb_dealloc_cmap(&info->cmap); kfree(info->pseudo_palette); } - if (remapped_fbuf != NULL) + if (remapped_fbuf != NULL) { iounmap(remapped_fbuf); - if (remapped_regs != NULL) + remapped_fbuf = NULL; + } + if (remapped_regs != NULL) { iounmap(remapped_regs); - if (remapped_base != NULL) + remapped_regs = NULL; + } + if (remapped_base != NULL) { iounmap(remapped_base); + remapped_base = NULL; + } if (info) framebuffer_release(info); return err; @@ -795,8 +801,11 @@ static int w100fb_remove(struct platform_device *pdev) fb_dealloc_cmap(&info->cmap);
iounmap(remapped_base); + remapped_base = NULL; iounmap(remapped_regs); + remapped_regs = NULL; iounmap(remapped_fbuf); + remapped_fbuf = NULL;
framebuffer_release(info);