From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E922E14C5B4; Sun, 24 Mar 2024 23:17:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711322245; cv=none; b=U+A1LFiZnhwZ3xDCkYjLmlGjE1RsE+9vqWofzySpbnOl1nNcXdbVHsf34JU0l/sn1EL/bB3LaB/764rjA+maJb0FTiNBims7lA6uzX8RG2oXPVZrpZTAvLWwg5cJQlLk+OB0dhb8MiQmdIiNzcUokrxZSwzQGEcictWbPMR273w= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711322245; c=relaxed/simple; bh=vY/fC/eRi3EUQWBPfjVdjNpnum2oqCLfcU1o+uebky4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=Vh89MVAkVs4xnI72Cd2Go/1TBw+TfQjtoMVAJp/ZHX/M2dWVJ0ysEaDEb6CJF14hLhsA00KXUkozZH0cJt+0GqJ8NkMMhzhicQto/Qhpaa3RNhG9O78UZglgF3c+QWGTH0YSHoKkqjJNg/JQnrHlZE3kr41zPFWyVB4WsPK4V1E= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=iVG1qxI8; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="iVG1qxI8" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1CC43C43390; Sun, 24 Mar 2024 23:17:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1711322243; bh=vY/fC/eRi3EUQWBPfjVdjNpnum2oqCLfcU1o+uebky4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iVG1qxI8dUurNikJChHKxNpaeg4IucEltKLCfBdkKSSlTwgMpnn2sucBZvywgfnQb wuEtyy78LNVsZml4Ivyig8D5A/HJq+P6us+NFxteLQYe0fd3SW2UeWd118RMYSFVtL Z57TVmTOwpQ4x1Nt2tgcaxhZVd9G8hEI6Rnb6tAx5poDLW2W2GfGUNdvuEbQiLbepC AujZjccZTnjMA9AqBuw535ltfg6mbAym9E+GAfB0pgUiKcgFfzdQ/gwoI8e+hPLCE9 0Ih9uZDV4FPF+UrPI2LsIntepPA/yK4oC1NxVB9B+IBm139ZmZiPsEyXkZpNwWmTBm iABDJiKAZrFmg== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Arnd Bergmann , Justin Stitt , Hans Verkuil , Sasha Levin Subject: [PATCH 6.1 325/451] media: dvb-frontends: avoid stack overflow warnings with clang Date: Sun, 24 Mar 2024 19:10:01 -0400 Message-ID: <20240324231207.1351418-326-sashal@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240324231207.1351418-1-sashal@kernel.org> References: <20240324231207.1351418-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit From: Arnd Bergmann [ Upstream commit 7a4cf27d1f0538f779bf31b8c99eda394e277119 ] A previous patch worked around a KASAN issue in stv0367, now a similar problem showed up with clang: drivers/media/dvb-frontends/stv0367.c:1222:12: error: stack frame size (3624) exceeds limit (2048) in 'stv0367ter_set_frontend' [-Werror,-Wframe-larger-than] 1214 | static int stv0367ter_set_frontend(struct dvb_frontend *fe) Rework the stv0367_writereg() function to be simpler and mark both register access functions as noinline_for_stack so the temporary i2c_msg structures do not get duplicated on the stack when KASAN_STACK is enabled. Fixes: 3cd890dbe2a4 ("media: dvb-frontends: fix i2c access helpers for KASAN") Signed-off-by: Arnd Bergmann Reviewed-by: Justin Stitt Signed-off-by: Hans Verkuil Signed-off-by: Sasha Levin --- drivers/media/dvb-frontends/stv0367.c | 34 +++++++-------------------- 1 file changed, 8 insertions(+), 26 deletions(-) diff --git a/drivers/media/dvb-frontends/stv0367.c b/drivers/media/dvb-frontends/stv0367.c index 04556b77c16c9..0977564a4a1a4 100644 --- a/drivers/media/dvb-frontends/stv0367.c +++ b/drivers/media/dvb-frontends/stv0367.c @@ -118,50 +118,32 @@ static const s32 stv0367cab_RF_LookUp2[RF_LOOKUP_TABLE2_SIZE][RF_LOOKUP_TABLE2_S } }; -static -int stv0367_writeregs(struct stv0367_state *state, u16 reg, u8 *data, int len) +static noinline_for_stack +int stv0367_writereg(struct stv0367_state *state, u16 reg, u8 data) { - u8 buf[MAX_XFER_SIZE]; + u8 buf[3] = { MSB(reg), LSB(reg), data }; struct i2c_msg msg = { .addr = state->config->demod_address, .flags = 0, .buf = buf, - .len = len + 2 + .len = 3, }; int ret; - if (2 + len > sizeof(buf)) { - printk(KERN_WARNING - "%s: i2c wr reg=%04x: len=%d is too big!\n", - KBUILD_MODNAME, reg, len); - return -EINVAL; - } - - - buf[0] = MSB(reg); - buf[1] = LSB(reg); - memcpy(buf + 2, data, len); - if (i2cdebug) printk(KERN_DEBUG "%s: [%02x] %02x: %02x\n", __func__, - state->config->demod_address, reg, buf[2]); + state->config->demod_address, reg, data); ret = i2c_transfer(state->i2c, &msg, 1); if (ret != 1) printk(KERN_ERR "%s: i2c write error! ([%02x] %02x: %02x)\n", - __func__, state->config->demod_address, reg, buf[2]); + __func__, state->config->demod_address, reg, data); return (ret != 1) ? -EREMOTEIO : 0; } -static int stv0367_writereg(struct stv0367_state *state, u16 reg, u8 data) -{ - u8 tmp = data; /* see gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 */ - - return stv0367_writeregs(state, reg, &tmp, 1); -} - -static u8 stv0367_readreg(struct stv0367_state *state, u16 reg) +static noinline_for_stack +u8 stv0367_readreg(struct stv0367_state *state, u16 reg) { u8 b0[] = { 0, 0 }; u8 b1[] = { 0 }; -- 2.43.0