From mboxrd@z Thu Jan 1 00:00:00 1970 From: Matt Fleming Subject: [PATCH 2/6] efi: Fix handling error value in fdt_find_uefi_params Date: Mon, 5 Sep 2016 15:42:33 +0100 Message-ID: <20160905144237.2361-3-matt@codeblueprint.co.uk> References: <20160905144237.2361-1-matt@codeblueprint.co.uk> Return-path: In-Reply-To: <20160905144237.2361-1-matt-mF/unelCI9GS6iBeEJttW/XRex20P6io@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Ingo Molnar , Thomas Gleixner , "H . Peter Anvin" Cc: Andrzej Hajda , Ard Biesheuvel , linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Matt Fleming , Bartlomiej Zolnierkiewicz , Marek Szyprowski , Mark Rutland , Shawn Lin , stable-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-efi@vger.kernel.org From: Andrzej Hajda of_get_flat_dt_subnode_by_name can return negative value in case of error. Assigning the result to unsigned variable and checking if the variable is lesser than zero is incorrect and always false. The patch fixes it by using signed variable to check the result. The problem has been detected using semantic patch scripts/coccinelle/tests/unsigned_lesser_than_zero.cocci Signed-off-by: Andrzej Hajda Cc: Bartlomiej Zolnierkiewicz Cc: Marek Szyprowski Cc: Ingo Molnar Cc: Thomas Gleixner Cc: "H. Peter Anvin" Cc: Shawn Lin Cc: Mark Rutland Cc: Signed-off-by: Matt Fleming --- drivers/firmware/efi/efi.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 5a2631af7410..7dd2e2d37231 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -657,9 +657,12 @@ static int __init fdt_find_uefi_params(unsigned long node, const char *uname, } if (subnode) { - node = of_get_flat_dt_subnode_by_name(node, subnode); - if (node < 0) + int err = of_get_flat_dt_subnode_by_name(node, subnode); + + if (err < 0) return 0; + + node = err; } return __find_uefi_params(node, info, dt_params[i].params); -- 2.9.3