From patchwork Fri Sep 18 10:09:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Arnd Bergmann X-Patchwork-Id: 293241 From: Arnd Bergmann Date: Fri, 18 Sep 2020 10:09:06 +0000 Subject: [PATCH 3/3] fbdev: sbuslib: remove compat_alloc_user_space usage Message-Id: <20200918100926.1447563-3-arnd@arndb.de> List-Id: References: <20200918100812.1447443-1-arnd@arndb.de> In-Reply-To: <20200918100812.1447443-1-arnd@arndb.de> MIME-Version: 1.0 To: linux-fbdev@vger.kernel.org, Bartlomiej Zolnierkiewicz Cc: "David S . Miller" , Arnd Bergmann , hch@lst.de, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org This is one of the last users of compat_alloc_user_space() and copy_in_user(). The actual handler is implemented in the same file and could be shared, but as I couldn't test this properly I leave the native case alone and just make a straight copy of it for the compat case, with a minimum set of modifications. Signed-off-by: Arnd Bergmann --- drivers/video/fbdev/sbuslib.c | 95 ++++++++++++++++++++++++++--------- 1 file changed, 70 insertions(+), 25 deletions(-) diff --git a/drivers/video/fbdev/sbuslib.c b/drivers/video/fbdev/sbuslib.c index f728db9bcff8..da28c279a54b 100644 --- a/drivers/video/fbdev/sbuslib.c +++ b/drivers/video/fbdev/sbuslib.c @@ -192,28 +192,6 @@ int sbusfb_ioctl_helper(unsigned long cmd, unsigned long arg, EXPORT_SYMBOL(sbusfb_ioctl_helper); #ifdef CONFIG_COMPAT -static int fbiogetputcmap(struct fb_info *info, unsigned int cmd, unsigned long arg) -{ - struct fbcmap32 __user *argp = (void __user *)arg; - struct fbcmap __user *p = compat_alloc_user_space(sizeof(*p)); - u32 addr; - int ret; - - ret = copy_in_user(p, argp, 2 * sizeof(int)); - ret |= get_user(addr, &argp->red); - ret |= put_user(compat_ptr(addr), &p->red); - ret |= get_user(addr, &argp->green); - ret |= put_user(compat_ptr(addr), &p->green); - ret |= get_user(addr, &argp->blue); - ret |= put_user(compat_ptr(addr), &p->blue); - if (ret) - return -EFAULT; - return info->fbops->fb_ioctl(info, - (cmd = FBIOPUTCMAP32) ? - FBIOPUTCMAP_SPARC : FBIOGETCMAP_SPARC, - (unsigned long)p); -} - int sbusfb_compat_ioctl(struct fb_info *info, unsigned int cmd, unsigned long arg) { switch (cmd) { @@ -230,9 +208,76 @@ int sbusfb_compat_ioctl(struct fb_info *info, unsigned int cmd, unsigned long ar case FBIOGCURMAX: return info->fbops->fb_ioctl(info, cmd, arg); case FBIOPUTCMAP32: - return fbiogetputcmap(info, cmd, arg); - case FBIOGETCMAP32: - return fbiogetputcmap(info, cmd, arg); + case FBIOPUTCMAP_SPARC: { + struct fbcmap32 c; + struct fb_cmap cmap; + u16 red, green, blue; + u8 red8, green8, blue8; + unsigned char __user *ured; + unsigned char __user *ugreen; + unsigned char __user *ublue; + unsigned int i; + + if (copy_from_user(&c, compat_ptr(arg), sizeof(c))) + return -EFAULT; + ured = compat_ptr(c.red); + ugreen = compat_ptr(c.green); + ublue = compat_ptr(c.blue); + + cmap.len = 1; + cmap.red = &red; + cmap.green = &green; + cmap.blue = &blue; + cmap.transp = NULL; + for (i = 0; i < c.count; i++) { + int err; + + if (get_user(red8, &ured[i]) || + get_user(green8, &ugreen[i]) || + get_user(blue8, &ublue[i])) + return -EFAULT; + + red = red8 << 8; + green = green8 << 8; + blue = blue8 << 8; + + cmap.start = c.index + i; + err = fb_set_cmap(&cmap, info); + if (err) + return err; + } + return 0; + } + case FBIOGETCMAP32: { + struct fbcmap32 c; + unsigned char __user *ured; + unsigned char __user *ugreen; + unsigned char __user *ublue; + struct fb_cmap *cmap = &info->cmap; + unsigned int index, i; + u8 red, green, blue; + + if (copy_from_user(&c, compat_ptr(arg), sizeof(c))) + return -EFAULT; + index = c.index; + ured = compat_ptr(c.red); + ugreen = compat_ptr(c.green); + ublue = compat_ptr(c.blue); + + if (index > cmap->len || c.count > cmap->len - index) + return -EINVAL; + + for (i = 0; i < c.count; i++) { + red = cmap->red[index + i] >> 8; + green = cmap->green[index + i] >> 8; + blue = cmap->blue[index + i] >> 8; + if (put_user(red, &ured[i]) || + put_user(green, &ugreen[i]) || + put_user(blue, &ublue[i])) + return -EFAULT; + } + return 0; + } default: return -ENOIOCTLCMD; }