[PATCH AUTOSEL 6.2 01/25] ARM: 9290/1: uaccess: Fix KASAN false-positives

[PATCH AUTOSEL 6.2 01/25] ARM: 9290/1: uaccess: Fix KASAN false-positives

[Sasha Levin]

From: Andrew Jeffery <andrew@aj.id.au>

[ Upstream commit ceac10c83b330680cc01ceaaab86cd49f4f30d81 ]

__copy_to_user_memcpy() and __clear_user_memset() had been calling
memcpy() and memset() respectively, leading to false-positive KASAN
reports when starting userspace:

    [   10.707901] Run /init as init process
    [   10.731892] process '/bin/busybox' started with executable stack
    [   10.745234] ==================================================================
    [   10.745796] BUG: KASAN: user-memory-access in __clear_user_memset+0x258/0x3ac
    [   10.747260] Write of size 2687 at addr 000de581 by task init/1

Use __memcpy() and __memset() instead to allow userspace access, which
is of course the intent of these functions.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Signed-off-by: Zev Weiss <zev@bewilderbeest.net>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/arm/lib/uaccess_with_memcpy.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/arm/lib/uaccess_with_memcpy.c b/arch/arm/lib/uaccess_with_memcpy.c
index 14eecaaf295fa..e4c2677cc1e9e 100644
--- a/arch/arm/lib/uaccess_with_memcpy.c
+++ b/arch/arm/lib/uaccess_with_memcpy.c
@@ -116,7 +116,7 @@ __copy_to_user_memcpy(void __user *to, const void *from, unsigned long n)
 			tocopy = n;
 
 		ua_flags = uaccess_save_and_enable();
-		memcpy((void *)to, from, tocopy);
+		__memcpy((void *)to, from, tocopy);
 		uaccess_restore(ua_flags);
 		to += tocopy;
 		from += tocopy;
@@ -178,7 +178,7 @@ __clear_user_memset(void __user *addr, unsigned long n)
 			tocopy = n;
 
 		ua_flags = uaccess_save_and_enable();
-		memset((void *)addr, 0, tocopy);
+		__memset((void *)addr, 0, tocopy);
 		uaccess_restore(ua_flags);
 		addr += tocopy;
 		n -= tocopy;
-- 
2.39.2


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[PATCH AUTOSEL 6.2 09/25] i2c: imx-lpi2c: clean rx/tx buffers upon new message

[Sasha Levin]

From: Alexander Stein <alexander.stein@ew.tq-group.com>

[ Upstream commit 987dd36c0141f6ab9f0fbf14d6b2ec3342dedb2f ]

When start sending a new message clear the Rx & Tx buffer pointers in
order to avoid using stale pointers.

Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Tested-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/i2c/busses/i2c-imx-lpi2c.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/i2c/busses/i2c-imx-lpi2c.c b/drivers/i2c/busses/i2c-imx-lpi2c.c
index 9b2f9544c5681..a49b14d52a986 100644
--- a/drivers/i2c/busses/i2c-imx-lpi2c.c
+++ b/drivers/i2c/busses/i2c-imx-lpi2c.c
@@ -463,6 +463,8 @@ static int lpi2c_imx_xfer(struct i2c_adapter *adapter,
 		if (num == 1 && msgs[0].len == 0)
 			goto stop;
 
+		lpi2c_imx->rx_buf = NULL;
+		lpi2c_imx->tx_buf = NULL;
 		lpi2c_imx->delivered = 0;
 		lpi2c_imx->msglen = msgs[i].len;
 		init_completion(&lpi2c_imx->complete);
-- 
2.39.2


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