[PATCH 4.19 348/421] Input: hideep - fix the uninitialized use in hideep_nvm_unlock()

Greg Kroah-Hartman
2021-07-19T16:33:23Z

From: Yizhuo Zhai <yzhai003@ucr.edu>

[ Upstream commit cac7100d4c51c04979dacdfe6c9a5e400d3f0a27 ]

Inside function hideep_nvm_unlock(), variable "unmask_code" could
be uninitialized if hideep_pgm_r_reg() returns error, however, it
is used in the later if statement after an "and" operation, which
is potentially unsafe.

Signed-off-by: Yizhuo <yzhai003@ucr.edu>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/input/touchscreen/hideep.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/drivers/input/touchscreen/hideep.c b/drivers/input/touchscreen/hideep.c
index f1cd4dd9a4a3..d7775db0b711 100644
--- a/drivers/input/touchscreen/hideep.c
+++ b/drivers/input/touchscreen/hideep.c
@@ -364,13 +364,16 @@ static int hideep_enter_pgm(struct hideep_ts *ts)
return -EIO;
}

-static void hideep_nvm_unlock(struct hideep_ts *ts)
+static int hideep_nvm_unlock(struct hideep_ts *ts)
{
u32 unmask_code;
+ int error;

hideep_pgm_w_reg(ts, HIDEEP_FLASH_CFG, HIDEEP_NVM_SFR_RPAGE);
- hideep_pgm_r_reg(ts, 0x0000000C, &unmask_code);
+ error = hideep_pgm_r_reg(ts, 0x0000000C, &unmask_code);
hideep_pgm_w_reg(ts, HIDEEP_FLASH_CFG, HIDEEP_NVM_DEFAULT_PAGE);
+ if (error)
+ return error;

/* make it unprotected code */
unmask_code &= ~HIDEEP_PROT_MODE;
@@ -387,6 +390,8 @@ static void hideep_nvm_unlock(struct hideep_ts *ts)
NVM_W_SFR(HIDEEP_NVM_MASK_OFS, ts->nvm_mask);
SET_FLASH_HWCONTROL();
hideep_pgm_w_reg(ts, HIDEEP_FLASH_CFG, HIDEEP_NVM_DEFAULT_PAGE);
+
+ return 0;
}

static int hideep_check_status(struct hideep_ts *ts)
@@ -465,7 +470,9 @@ static int hideep_program_nvm(struct hideep_ts *ts,
u32 addr = 0;
int error;

- hideep_nvm_unlock(ts);
+ error = hideep_nvm_unlock(ts);
+ if (error)
+ return error;

while (ucode_len > 0) {
xfer_len = min_t(size_t, ucode_len, HIDEEP_NVM_PAGE_SIZE);
--
2.30.2