From 3ab8a64d002c752672f5bb44029e9991e8a11d47 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Tue, 8 Nov 2022 13:37:55 +0100 Subject: ARM: ux500: do not directly dereference __iomem commit 65b0e307a1a9193571db12910f382f84195a3d29 upstream. Sparse reports that calling add_device_randomness() on `uid` is a violation of address spaces. And indeed the next usage uses readl() properly, but that was left out when passing it toadd_device_ randomness(). So instead copy the whole thing to the stack first. Fixes: 4040d10a3d44 ("ARM: ux500: add DB serial number to entropy pool") Cc: Linus Walleij Cc: stable@vger.kernel.org Link: https://lore.kernel.org/all/202210230819.loF90KDh-lkp@intel.com/ Reported-by: kernel test robot Signed-off-by: Jason A. Donenfeld Link: https://lore.kernel.org/r/20221108123755.207438-1-Jason@zx2c4.com Signed-off-by: Linus Walleij Signed-off-by: Greg Kroah-Hartman --- drivers/soc/ux500/ux500-soc-id.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/drivers/soc/ux500/ux500-soc-id.c b/drivers/soc/ux500/ux500-soc-id.c index 6c1be74e5fcc..86a1a3c408df 100644 --- a/drivers/soc/ux500/ux500-soc-id.c +++ b/drivers/soc/ux500/ux500-soc-id.c @@ -159,20 +159,18 @@ static ssize_t ux500_get_process(struct device *dev, static const char *db8500_read_soc_id(struct device_node *backupram) { void __iomem *base; - void __iomem *uid; const char *retstr; + u32 uid[5]; base = of_iomap(backupram, 0); if (!base) return NULL; - uid = base + 0x1fc0; + memcpy_fromio(uid, base + 0x1fc0, sizeof(uid)); /* Throw these device-specific numbers into the entropy pool */ - add_device_randomness(uid, 0x14); + add_device_randomness(uid, sizeof(uid)); retstr = kasprintf(GFP_KERNEL, "%08x%08x%08x%08x%08x", - readl((u32 *)uid+0), - readl((u32 *)uid+1), readl((u32 *)uid+2), - readl((u32 *)uid+3), readl((u32 *)uid+4)); + uid[0], uid[1], uid[2], uid[3], uid[4]); iounmap(base); return retstr; } -- cgit v1.2.3