mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-12 05:48:40 +00:00
Code Issues Releases Wiki Activity

lkdtm: split atomic test into over and underflow

Browse source 
Each direction of the atomic wrapping should be individually testable.

Signed-off-by: Kees Cook <keescook@chromium.org>
This commit is contained in:
Kees Cook 2016-06-07 14:27:02 -07:00
parent aa981a665d
commit b54845276a
1 changed files with 20 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

26
drivers/misc/lkdtm_core.c
View file

@ -111,7 +111,8 @@ enum ctype {
CT_WRITE_RO,
CT_WRITE_RO_AFTER_INIT,
CT_WRITE_KERN,
CT_WRAP_ATOMIC,
CT_ATOMIC_UNDERFLOW,
CT_ATOMIC_OVERFLOW,
CT_USERCOPY_HEAP_SIZE_TO,
CT_USERCOPY_HEAP_SIZE_FROM,
CT_USERCOPY_HEAP_FLAG_TO,
@ -161,7 +162,8 @@ static char* cp_type[] = {
"WRITE_RO",
"WRITE_RO_AFTER_INIT",
"WRITE_KERN",
"WRAP_ATOMIC",
"ATOMIC_UNDERFLOW",
"ATOMIC_OVERFLOW",
"USERCOPY_HEAP_SIZE_TO",
"USERCOPY_HEAP_SIZE_FROM",
"USERCOPY_HEAP_FLAG_TO",
@ -911,13 +913,25 @@ static void lkdtm_do_action(enum ctype which)
do_overwritten();
break;
}
case CT_WRAP_ATOMIC: {
case CT_ATOMIC_UNDERFLOW: {
atomic_t under = ATOMIC_INIT(INT_MIN);
pr_info("attempting good atomic increment\n");
atomic_inc(&under);
atomic_dec(&under);
pr_info("attempting bad atomic underflow\n");
atomic_dec(&under);
break;
}
case CT_ATOMIC_OVERFLOW: {
atomic_t over = ATOMIC_INIT(INT_MAX);
pr_info("attempting atomic underflow\n");
atomic_dec(&under);
pr_info("attempting atomic overflow\n");
pr_info("attempting good atomic decrement\n");
atomic_dec(&over);
atomic_inc(&over);
pr_info("attempting bad atomic overflow\n");
atomic_inc(&over);
return;