]> www.infradead.org Git - users/jedix/linux-maple.git/commit
x86/mtrr: Don't copy uninitialized gentry fields back to userspace
authorColin Ian King <colin.king@canonical.com>
Tue, 18 Dec 2018 17:29:56 +0000 (17:29 +0000)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 29 Dec 2018 12:39:10 +0000 (13:39 +0100)
commit0761921fa6cbe6859b7994eb77811f100adb9ffe
tree09d25d2333007824e29ef6e7e7ebc895b2b2af84
parentff53cc3576d3d728dec87e866c3ae84e33ef07a8
x86/mtrr: Don't copy uninitialized gentry fields back to userspace

commit 32043fa065b51e0b1433e48d118821c71b5cd65d upstream.

Currently the copy_to_user of data in the gentry struct is copying
uninitiaized data in field _pad from the stack to userspace.

Fix this by explicitly memset'ing gentry to zero, this also will zero any
compiler added padding fields that may be in struct (currently there are
none).

Detected by CoverityScan, CID#200783 ("Uninitialized scalar variable")

Fixes: b263b31e8ad6 ("x86, mtrr: Use explicit sizing and padding for the 64-bit ioctls")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Tyler Hicks <tyhicks@canonical.com>
Cc: security@kernel.org
Link: https://lkml.kernel.org/r/20181218172956.1440-1-colin.king@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kernel/cpu/mtrr/if.c