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authorLinus Torvalds <torvalds@linux-foundation.org>2019-06-08 22:50:36 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2019-06-08 22:50:36 +0300
commit1ce2c85137b1db5b0e4158d558cb93dcff7674df (patch)
tree37f62adbc031e12747ba71f14b304edb8445fa82 /drivers/misc/lkdtm
parent902b2edfca34f88b04b86e605087e200e7e79880 (diff)
parente7bf2ce837475445bfd44ac1193ced0684a70d96 (diff)
downloadlinux-1ce2c85137b1db5b0e4158d558cb93dcff7674df.tar.xz
Merge tag 'char-misc-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver fixes from Greg KH: "Here are some small char and misc driver fixes for 5.2-rc4 to resolve a number of reported issues. The most "notable" one here is the kernel headers in proc^Wsysfs fixes. Those changes move the header file info into sysfs and fixes the build issues that you reported. Other than that, a bunch of small habanalabs driver fixes, some fpga driver fixes, and a few other tiny driver fixes. All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.2-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: habanalabs: Read upper bits of trace buffer from RWPHI habanalabs: Fix virtual address access via debugfs for 2MB pages fpga: zynqmp-fpga: Correctly handle error pointer habanalabs: fix bug in checking huge page optimization habanalabs: Avoid using a non-initialized MMU cache mutex habanalabs: fix debugfs code uapi/habanalabs: add opcode for enable/disable device debug mode habanalabs: halt debug engines on user process close test_firmware: Use correct snprintf() limit genwqe: Prevent an integer overflow in the ioctl parport: Fix mem leak in parport_register_dev_model fpga: dfl: expand minor range when registering chrdev region fpga: dfl: Add lockdep classes for pdata->lock fpga: dfl: afu: Pass the correct device to dma_mapping_error() fpga: stratix10-soc: fix use-after-free on s10_init() w1: ds2408: Fix typo after 49695ac46861 (reset on output_write retry with readback) kheaders: Do not regenerate archive if config is not changed kheaders: Move from proc to sysfs lkdtm/bugs: Adjust recursion test to avoid elision lkdtm/usercopy: Moves the KERNEL_DS test to non-canonical
Diffstat (limited to 'drivers/misc/lkdtm')
-rw-r--r--drivers/misc/lkdtm/bugs.c23
-rw-r--r--drivers/misc/lkdtm/core.c6
-rw-r--r--drivers/misc/lkdtm/lkdtm.h2
-rw-r--r--drivers/misc/lkdtm/usercopy.c10
4 files changed, 27 insertions, 14 deletions
diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c
index 7eebbdfbcacd..17f839dee976 100644
--- a/drivers/misc/lkdtm/bugs.c
+++ b/drivers/misc/lkdtm/bugs.c
@@ -32,12 +32,20 @@ static int recur_count = REC_NUM_DEFAULT;
static DEFINE_SPINLOCK(lock_me_up);
-static int recursive_loop(int remaining)
+/*
+ * Make sure compiler does not optimize this function or stack frame away:
+ * - function marked noinline
+ * - stack variables are marked volatile
+ * - stack variables are written (memset()) and read (pr_info())
+ * - function has external effects (pr_info())
+ * */
+static int noinline recursive_loop(int remaining)
{
- char buf[REC_STACK_SIZE];
+ volatile char buf[REC_STACK_SIZE];
- /* Make sure compiler does not optimize this away. */
- memset(buf, (remaining & 0xff) | 0x1, REC_STACK_SIZE);
+ memset((void *)buf, remaining & 0xFF, sizeof(buf));
+ pr_info("loop %d/%d ...\n", (int)buf[remaining % sizeof(buf)],
+ recur_count);
if (!remaining)
return 0;
else
@@ -81,9 +89,12 @@ void lkdtm_LOOP(void)
;
}
-void lkdtm_OVERFLOW(void)
+void lkdtm_EXHAUST_STACK(void)
{
- (void) recursive_loop(recur_count);
+ pr_info("Calling function with %d frame size to depth %d ...\n",
+ REC_STACK_SIZE, recur_count);
+ recursive_loop(recur_count);
+ pr_info("FAIL: survived without exhausting stack?!\n");
}
static noinline void __lkdtm_CORRUPT_STACK(void *stack)
diff --git a/drivers/misc/lkdtm/core.c b/drivers/misc/lkdtm/core.c
index 1972dad966f5..8a1428d4f138 100644
--- a/drivers/misc/lkdtm/core.c
+++ b/drivers/misc/lkdtm/core.c
@@ -106,12 +106,12 @@ static const struct crashtype crashtypes[] = {
CRASHTYPE(WARNING),
CRASHTYPE(EXCEPTION),
CRASHTYPE(LOOP),
- CRASHTYPE(OVERFLOW),
+ CRASHTYPE(EXHAUST_STACK),
+ CRASHTYPE(CORRUPT_STACK),
+ CRASHTYPE(CORRUPT_STACK_STRONG),
CRASHTYPE(CORRUPT_LIST_ADD),
CRASHTYPE(CORRUPT_LIST_DEL),
CRASHTYPE(CORRUPT_USER_DS),
- CRASHTYPE(CORRUPT_STACK),
- CRASHTYPE(CORRUPT_STACK_STRONG),
CRASHTYPE(STACK_GUARD_PAGE_LEADING),
CRASHTYPE(STACK_GUARD_PAGE_TRAILING),
CRASHTYPE(UNALIGNED_LOAD_STORE_WRITE),
diff --git a/drivers/misc/lkdtm/lkdtm.h b/drivers/misc/lkdtm/lkdtm.h
index b69ee004a3f7..23dc565b4307 100644
--- a/drivers/misc/lkdtm/lkdtm.h
+++ b/drivers/misc/lkdtm/lkdtm.h
@@ -13,7 +13,7 @@ void lkdtm_BUG(void);
void lkdtm_WARNING(void);
void lkdtm_EXCEPTION(void);
void lkdtm_LOOP(void);
-void lkdtm_OVERFLOW(void);
+void lkdtm_EXHAUST_STACK(void);
void lkdtm_CORRUPT_STACK(void);
void lkdtm_CORRUPT_STACK_STRONG(void);
void lkdtm_UNALIGNED_LOAD_STORE_WRITE(void);
diff --git a/drivers/misc/lkdtm/usercopy.c b/drivers/misc/lkdtm/usercopy.c
index d5a0e7f1813b..e172719dd86d 100644
--- a/drivers/misc/lkdtm/usercopy.c
+++ b/drivers/misc/lkdtm/usercopy.c
@@ -324,14 +324,16 @@ free_user:
void lkdtm_USERCOPY_KERNEL_DS(void)
{
- char __user *user_ptr = (char __user *)ERR_PTR(-EINVAL);
+ char __user *user_ptr =
+ (char __user *)(0xFUL << (sizeof(unsigned long) * 8 - 4));
mm_segment_t old_fs = get_fs();
char buf[10] = {0};
- pr_info("attempting copy_to_user on unmapped kernel address\n");
+ pr_info("attempting copy_to_user() to noncanonical address: %px\n",
+ user_ptr);
set_fs(KERNEL_DS);
- if (copy_to_user(user_ptr, buf, sizeof(buf)))
- pr_info("copy_to_user un unmapped kernel address failed\n");
+ if (copy_to_user(user_ptr, buf, sizeof(buf)) == 0)
+ pr_err("copy_to_user() to noncanonical address succeeded!?\n");
set_fs(old_fs);
}