From: Colin Ian King Date: Mon, 20 Mar 2017 11:51:23 +0000 (+0000) Subject: i2c: designware-baytrail: fix potential null pointer dereference on dev X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=c7f82ea8605627b3088f166d9f4a5ca7857e8383;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git i2c: designware-baytrail: fix potential null pointer dereference on dev The assignment to addr requires a call to get_sem_addr that dereferences dev, however, this dereference occurs before a null pointer check on dev. Move this assignment after the null check on dev to avoid a potential null pointer dereference. Detected by CoverityScan, CID#1419700 ("Dereference before null check") Fixes: fd476fa22a1f432 ("i2c: designware-baytrail: Add support for cherrytrail") Signed-off-by: Colin Ian King Signed-off-by: Wolfram Sang --- diff --git a/drivers/i2c/busses/i2c-designware-baytrail.c b/drivers/i2c/busses/i2c-designware-baytrail.c index 1ac042972020..dbda8c9c8a1c 100644 --- a/drivers/i2c/busses/i2c-designware-baytrail.c +++ b/drivers/i2c/busses/i2c-designware-baytrail.c @@ -70,7 +70,7 @@ static void reset_semaphore(struct dw_i2c_dev *dev) static int baytrail_i2c_acquire(struct dw_i2c_dev *dev) { - u32 addr = get_sem_addr(dev); + u32 addr; u32 sem = PUNIT_SEMAPHORE_ACQUIRE; int ret; unsigned long start, end; @@ -94,6 +94,8 @@ static int baytrail_i2c_acquire(struct dw_i2c_dev *dev) */ pm_qos_update_request(&dev->pm_qos, 0); + addr = get_sem_addr(dev); + /* host driver writes to side band semaphore register */ ret = iosf_mbi_write(BT_MBI_UNIT_PMC, MBI_REG_WRITE, addr, sem); if (ret) {