• Christophe Leroy's avatar
    lkdtm: Print real addresses · b035faf5
    Christophe Leroy authored
    [ Upstream commit 4c411157 ]
    
    Today, when doing a lkdtm test before the readiness of the
    random generator, (ptrval) is printed instead of the address
    at which it perform the fault:
    
    [ 1597.337030] lkdtm: Performing direct entry EXEC_USERSPACE
    [ 1597.337142] lkdtm: attempting ok execution at (ptrval)
    [ 1597.337398] lkdtm: attempting bad execution at (ptrval)
    [ 1597.337460] kernel tried to execute user page (77858000) -exploit attempt? (uid: 0)
    [ 1597.344769] Unable to handle kernel paging request for instruction fetch
    [ 1597.351392] Faulting instruction address: 0x77858000
    [ 1597.356312] Oops: Kernel access of bad area, sig: 11 [#1]
    
    If the lkdtm test is done later on, it prints an hashed address.
    
    In both cases this is pointless. The purpose of the test is to
    ensure the kernel generates an Oops at the expected address,
    so real addresses needs to be printed. This patch fixes that.
    Signed-off-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
    Signed-off-by: default avatarKees Cook <keescook@chromium.org>
    Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
    b035faf5
lkdtm_perms.c 4.66 KB