Patch "x86/pkeys/selftests: Fix pointer math" has been added to the 4.14-stable tree

This is a note to let you know that I've just added the patch titled

x86/pkeys/selftests: Fix pointer math

to the 4.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
x86-pkeys-selftests-fix-pointer-math.patch
and it can be found in the queue-4.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Dave Hansen <[email protected]>
Date: Wed, 9 May 2018 10:13:52 -0700
Subject: x86/pkeys/selftests: Fix pointer math

From: Dave Hansen <[email protected]>

[ Upstream commit 3d64f4ed15c3c53dba4c514bf59c334464dee373 ]

We dump out the entire area of the siginfo where the si_pkey_ptr is supposed to be. But, we do some math on the poitner, which is a u32. We intended to do byte math, not u32 math on the pointer.

Cast it over to a u8* so it works.

Also, move this block of code to below th si_code check. It doesn't hurt anything, but the si_pkey field is gibberish for other signal types.

---
 tools/testing/selftests/x86/protection_keys.c |   14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

@@ -303,13 +303,6 @@ void signal_handler(int signum, siginfo_
 		dump_mem(pkru_ptr - 128, 256);
 	pkey_assert(*pkru_ptr);
 
-	si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
-	dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
-	dump_mem(si_pkey_ptr - 8, 24);
-	siginfo_pkey = *si_pkey_ptr;
-	pkey_assert(siginfo_pkey < NR_PKEYS);
-	last_si_pkey = siginfo_pkey;
-
 	if ((si->si_code == SEGV_MAPERR) ||
 	    (si->si_code == SEGV_ACCERR) ||
 	    (si->si_code == SEGV_BNDERR)) {

@@ -317,6 +310,13 @@ void signal_handler(int signum, siginfo_
 		exit(4);
 	}
 
+	si_pkey_ptr = (u32 *)(((u8 *)si) + si_pkey_offset);
+	dprintf1("si_pkey_ptr: %p\n", si_pkey_ptr);
+	dump_mem((u8 *)si_pkey_ptr - 8, 24);
+	siginfo_pkey = *si_pkey_ptr;
+	pkey_assert(siginfo_pkey < NR_PKEYS);
+	last_si_pkey = siginfo_pkey;
+
 	dprintf1("signal pkru from xsave: %08x\n", *pkru_ptr);
 	/* need __rdpkru() version so we do not do shadow_pkru checking */
 	dprintf1("signal pkru from  pkru: %08x\n", __rdpkru());

Patches currently in stable-queue which might be from [email protected] are

queue-4.14/x86-pkeys-selftests-factor-out-instruction-page.patch queue-4.14/x86-pkeys-selftests-fix-pointer-math.patch queue-4.14/x86-pkeys-selftests-adjust-the-self-test-to-fresh-distros-that-export-the-pkeys-abi.patch queue-4.14/x86-pkeys-selftests-add-a-test-for-pkey-0.patch queue-4.14/x86-pkeys-selftests-stop-using-assert.patch queue-4.14/x86-pkeys-selftests-save-off-prot-for-allocations.patch queue-4.14/x86-pkeys-selftests-remove-dead-debugging-code-fix-dprint_in_signal.patch queue-4.14/x86-mpx-selftests-adjust-the-self-test-to-fresh-distros-that-export-the-mpx-abi.patch queue-4.14/x86-pkeys-selftests-add-prot_exec-test.patch queue-4.14/x86-pkeys-selftests-allow-faults-on-unknown-keys.patch queue-4.14/x86-pkeys-selftests-give-better-unexpected-fault-error-messages.patch queue-4.14/x86-pkeys-selftests-fix-pkey-exhaustion-test-off-by-one.patch