| Message ID | 20200817073212.830069-7-hch@lst.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [01/11] mem: remove duplicate ops for /dev/zero and /dev/null | expand |
On Mon, Aug 17, 2020 at 09:32:07AM +0200, Christoph Hellwig wrote: > Once we can't manipulate the address limit, we also can't test what > happens when the manipulation is abused. > > Signed-off-by: Christoph Hellwig <hch@lst.de> > --- > drivers/misc/lkdtm/bugs.c | 2 ++ > drivers/misc/lkdtm/core.c | 4 ++++ > drivers/misc/lkdtm/usercopy.c | 2 ++ > 3 files changed, 8 insertions(+) > > diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c > index 4dfbfd51bdf774..66f1800b1cb82d 100644 > --- a/drivers/misc/lkdtm/bugs.c > +++ b/drivers/misc/lkdtm/bugs.c > @@ -312,6 +312,7 @@ void lkdtm_CORRUPT_LIST_DEL(void) > pr_err("list_del() corruption not detected!\n"); > } > > +#ifdef CONFIG_SET_FS > /* Test if unbalanced set_fs(KERNEL_DS)/set_fs(USER_DS) check exists. */ > void lkdtm_CORRUPT_USER_DS(void) > { > @@ -321,6 +322,7 @@ void lkdtm_CORRUPT_USER_DS(void) > /* Make sure we do not keep running with a KERNEL_DS! */ > force_sig(SIGKILL); > } > +#endif Please let the test defined, but it should XFAIL with a message about the CONFIG (see similar ifdefs in lkdtm). > /* Test that VMAP_STACK is actually allocating with a leading guard page */ > void lkdtm_STACK_GUARD_PAGE_LEADING(void) > diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c > index a5e344df916632..aae08b33a7ee2a 100644 > --- a/drivers/misc/lkdtm/core.c > +++ b/drivers/misc/lkdtm/core.c > @@ -112,7 +112,9 @@ static const struct crashtype crashtypes[] = { > CRASHTYPE(CORRUPT_STACK_STRONG), > CRASHTYPE(CORRUPT_LIST_ADD), > CRASHTYPE(CORRUPT_LIST_DEL), > +#ifdef CONFIG_SET_FS > CRASHTYPE(CORRUPT_USER_DS), > +#endif > CRASHTYPE(STACK_GUARD_PAGE_LEADING), > CRASHTYPE(STACK_GUARD_PAGE_TRAILING), > CRASHTYPE(UNSET_SMEP), > @@ -172,7 +174,9 @@ static const struct crashtype crashtypes[] = { > CRASHTYPE(USERCOPY_STACK_FRAME_FROM), > CRASHTYPE(USERCOPY_STACK_BEYOND), > CRASHTYPE(USERCOPY_KERNEL), > +#ifdef CONFIG_SET_FS > CRASHTYPE(USERCOPY_KERNEL_DS), > +#endif > CRASHTYPE(STACKLEAK_ERASING), > CRASHTYPE(CFI_FORWARD_PROTO), Then none of these are needed. > #ifdef CONFIG_X86_32 Hmpf, this ifdef was missed in ae56942c1474 ("lkdtm: Make arch-specific tests always available"). I will fix that. > diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c > index b833367a45d053..4b632fe79ab6bb 100644 > --- a/drivers/misc/lkdtm/usercopy.c > +++ b/drivers/misc/lkdtm/usercopy.c > @@ -325,6 +325,7 @@ void lkdtm_USERCOPY_KERNEL(void) > vm_munmap(user_addr, PAGE_SIZE); > } > > +#ifdef CONFIG_SET_FS > void lkdtm_USERCOPY_KERNEL_DS(void) > { > char __user *user_ptr = > @@ -339,6 +340,7 @@ void lkdtm_USERCOPY_KERNEL_DS(void) > pr_err("copy_to_user() to noncanonical address succeeded!?\n"); > set_fs(old_fs); > } > +#endif (Same here, please.) > > void __init lkdtm_usercopy_init(void) > { > -- > 2.28.0 >
diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c index 4dfbfd51bdf774..66f1800b1cb82d 100644 --- a/drivers/misc/lkdtm/bugs.c +++ b/drivers/misc/lkdtm/bugs.c @@ -312,6 +312,7 @@ void lkdtm_CORRUPT_LIST_DEL(void) pr_err("list_del() corruption not detected!\n"); } +#ifdef CONFIG_SET_FS /* Test if unbalanced set_fs(KERNEL_DS)/set_fs(USER_DS) check exists. */ void lkdtm_CORRUPT_USER_DS(void) { @@ -321,6 +322,7 @@ void lkdtm_CORRUPT_USER_DS(void) /* Make sure we do not keep running with a KERNEL_DS! */ force_sig(SIGKILL); } +#endif /* Test that VMAP_STACK is actually allocating with a leading guard page */ void lkdtm_STACK_GUARD_PAGE_LEADING(void) diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c index a5e344df916632..aae08b33a7ee2a 100644 --- a/drivers/misc/lkdtm/core.c +++ b/drivers/misc/lkdtm/core.c @@ -112,7 +112,9 @@ static const struct crashtype crashtypes[] = { CRASHTYPE(CORRUPT_STACK_STRONG), CRASHTYPE(CORRUPT_LIST_ADD), CRASHTYPE(CORRUPT_LIST_DEL), +#ifdef CONFIG_SET_FS CRASHTYPE(CORRUPT_USER_DS), +#endif CRASHTYPE(STACK_GUARD_PAGE_LEADING), CRASHTYPE(STACK_GUARD_PAGE_TRAILING), CRASHTYPE(UNSET_SMEP), @@ -172,7 +174,9 @@ static const struct crashtype crashtypes[] = { CRASHTYPE(USERCOPY_STACK_FRAME_FROM), CRASHTYPE(USERCOPY_STACK_BEYOND), CRASHTYPE(USERCOPY_KERNEL), +#ifdef CONFIG_SET_FS CRASHTYPE(USERCOPY_KERNEL_DS), +#endif CRASHTYPE(STACKLEAK_ERASING), CRASHTYPE(CFI_FORWARD_PROTO), #ifdef CONFIG_X86_32 diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c index b833367a45d053..4b632fe79ab6bb 100644 --- a/drivers/misc/lkdtm/usercopy.c +++ b/drivers/misc/lkdtm/usercopy.c @@ -325,6 +325,7 @@ void lkdtm_USERCOPY_KERNEL(void) vm_munmap(user_addr, PAGE_SIZE); } +#ifdef CONFIG_SET_FS void lkdtm_USERCOPY_KERNEL_DS(void) { char __user *user_ptr = @@ -339,6 +340,7 @@ void lkdtm_USERCOPY_KERNEL_DS(void) pr_err("copy_to_user() to noncanonical address succeeded!?\n"); set_fs(old_fs); } +#endif void __init lkdtm_usercopy_init(void) {
Once we can't manipulate the address limit, we also can't test what happens when the manipulation is abused. Signed-off-by: Christoph Hellwig <hch@lst.de> --- drivers/misc/lkdtm/bugs.c | 2 ++ drivers/misc/lkdtm/core.c | 4 ++++ drivers/misc/lkdtm/usercopy.c | 2 ++ 3 files changed, 8 insertions(+)