From ea9e1ca4093975a0ce346b60cfc18030c965006c Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Tue, 28 Mar 2017 12:11:07 +0200 Subject: [PATCH] isdn: kcapi: avoid uninitialized data [ Upstream commit af109a2cf6a9a6271fa420ae2d64d72d86c92b7d ] gcc-7 points out that the AVMB1_ADDCARD ioctl results in an unintialized value ending up in the cardnr parameter: drivers/isdn/capi/kcapi.c: In function 'old_capi_manufacturer': drivers/isdn/capi/kcapi.c:1042:24: error: 'cdef.cardnr' may be used uninitialized in this function [-Werror=maybe-uninitialized] cparams.cardnr = cdef.cardnr; This has been broken since before the start of the git history, so either the value is not used for anything important, or the ioctl command doesn't get called in practice. Setting the cardnr to zero avoids the warning and makes sure we have consistent behavior. Signed-off-by: Arnd Bergmann Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/isdn/capi/kcapi.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/isdn/capi/kcapi.c b/drivers/isdn/capi/kcapi.c index 823f6985b260..dd7e38ac29bd 100644 --- a/drivers/isdn/capi/kcapi.c +++ b/drivers/isdn/capi/kcapi.c @@ -1032,6 +1032,7 @@ static int old_capi_manufacturer(unsigned int cmd, void __user *data) sizeof(avmb1_carddef)))) return -EFAULT; cdef.cardtype = AVM_CARDTYPE_B1; + cdef.cardnr = 0; } else { if ((retval = copy_from_user(&cdef, data, sizeof(avmb1_extcarddef)))) -- 2.20.1