5.10-stable patches

added patches:
	lkdtm-don-t-move-ctors-to-.rodata.patch

diff --git a/queue-5.10/lkdtm-don-t-move-ctors-to-.rodata.patch b/queue-5.10/lkdtm-don-t-move-ctors-to-.rodata.patch
new file mode 100644 (file)
index 0000000..21fe8da
--- /dev/null
+++ b/queue-5.10/lkdtm-don-t-move-ctors-to-.rodata.patch
@@ -0,0 +1,100 @@
+From 3f618ab3323407ee4c6a6734a37eb6e9663ebfb9 Mon Sep 17 00:00:00 2001
+From: Mark Rutland <mark.rutland@arm.com>
+Date: Mon, 7 Dec 2020 17:05:33 +0000
+Subject: lkdtm: don't move ctors to .rodata
+
+From: Mark Rutland <mark.rutland@arm.com>
+
+commit 3f618ab3323407ee4c6a6734a37eb6e9663ebfb9 upstream.
+
+When building with KASAN and LKDTM, clang may implictly generate an
+asan.module_ctor function in the LKDTM rodata object. The Makefile moves
+the lkdtm_rodata_do_nothing() function into .rodata by renaming the
+file's .text section to .rodata, and consequently also moves the ctor
+function into .rodata, leading to a boot time crash (splat below) when
+the ctor is invoked by do_ctors().
+
+Let's prevent this by marking the function as noinstr rather than
+notrace, and renaming the file's .noinstr.text to .rodata. Marking the
+function as noinstr will prevent tracing and kprobes, and will inhibit
+any undesireable compiler instrumentation.
+
+The ctor function (if any) will be placed in .text and will work
+correctly.
+
+Example splat before this patch is applied:
+
+[    0.916359] Unable to handle kernel execute from non-executable memory at virtual address ffffa0006b60f5ac
+[    0.922088] Mem abort info:
+[    0.922828]   ESR = 0x8600000e
+[    0.923635]   EC = 0x21: IABT (current EL), IL = 32 bits
+[    0.925036]   SET = 0, FnV = 0
+[    0.925838]   EA = 0, S1PTW = 0
+[    0.926714] swapper pgtable: 4k pages, 48-bit VAs, pgdp=00000000427b3000
+[    0.928489] [ffffa0006b60f5ac] pgd=000000023ffff003, p4d=000000023ffff003, pud=000000023fffe003, pmd=0068000042000f01
+[    0.931330] Internal error: Oops: 8600000e [#1] PREEMPT SMP
+[    0.932806] Modules linked in:
+[    0.933617] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.10.0-rc7 #2
+[    0.935620] Hardware name: linux,dummy-virt (DT)
+[    0.936924] pstate: 40400005 (nZcv daif +PAN -UAO -TCO BTYPE=--)
+[    0.938609] pc : asan.module_ctor+0x0/0x14
+[    0.939759] lr : do_basic_setup+0x4c/0x70
+[    0.940889] sp : ffff27b600177e30
+[    0.941815] x29: ffff27b600177e30 x28: 0000000000000000
+[    0.943306] x27: 0000000000000000 x26: 0000000000000000
+[    0.944803] x25: 0000000000000000 x24: 0000000000000000
+[    0.946289] x23: 0000000000000001 x22: 0000000000000000
+[    0.947777] x21: ffffa0006bf4a890 x20: ffffa0006befb6c0
+[    0.949271] x19: ffffa0006bef9358 x18: 0000000000000068
+[    0.950756] x17: fffffffffffffff8 x16: 0000000000000000
+[    0.952246] x15: 0000000000000000 x14: 0000000000000000
+[    0.953734] x13: 00000000838a16d5 x12: 0000000000000001
+[    0.955223] x11: ffff94000da74041 x10: dfffa00000000000
+[    0.956715] x9 : 0000000000000000 x8 : ffffa0006b60f5ac
+[    0.958199] x7 : f9f9f9f9f9f9f9f9 x6 : 000000000000003f
+[    0.959683] x5 : 0000000000000040 x4 : 0000000000000000
+[    0.961178] x3 : ffffa0006bdc15a0 x2 : 0000000000000005
+[    0.962662] x1 : 00000000000000f9 x0 : ffffa0006bef9350
+[    0.964155] Call trace:
+[    0.964844]  asan.module_ctor+0x0/0x14
+[    0.965895]  kernel_init_freeable+0x158/0x198
+[    0.967115]  kernel_init+0x14/0x19c
+[    0.968104]  ret_from_fork+0x10/0x30
+[    0.969110] Code: 00000003 00000000 00000000 00000000 (00000000)
+[    0.970815] ---[ end trace b5339784e20d015c ]---
+
+Cc: Arnd Bergmann <arnd@arndb.de>
+Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+Cc: Kees Cook <keescook@chromium.org>
+Acked-by: Kees Cook <keescook@chromium.org>
+Signed-off-by: Mark Rutland <mark.rutland@arm.com>
+Link: https://lore.kernel.org/r/20201207170533.10738-1-mark.rutland@arm.com
+Cc: Stephen Boyd <swboyd@chromium.org>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/misc/lkdtm/Makefile |    2 +-
+ drivers/misc/lkdtm/rodata.c |    2 +-
+ 2 files changed, 2 insertions(+), 2 deletions(-)
+
+--- a/drivers/misc/lkdtm/Makefile
++++ b/drivers/misc/lkdtm/Makefile
+@@ -16,7 +16,7 @@ KCOV_INSTRUMENT_rodata.o     := n
+ 
+ OBJCOPYFLAGS :=
+ OBJCOPYFLAGS_rodata_objcopy.o := \
+-                      --rename-section .text=.rodata,alloc,readonly,load
++                      --rename-section .noinstr.text=.rodata,alloc,readonly,load
+ targets += rodata.o rodata_objcopy.o
+ $(obj)/rodata_objcopy.o: $(obj)/rodata.o FORCE
+       $(call if_changed,objcopy)
+--- a/drivers/misc/lkdtm/rodata.c
++++ b/drivers/misc/lkdtm/rodata.c
+@@ -5,7 +5,7 @@
+  */
+ #include "lkdtm.h"
+ 
+-void notrace lkdtm_rodata_do_nothing(void)
++void noinstr lkdtm_rodata_do_nothing(void)
+ {
+       /* Does nothing. We just want an architecture agnostic "return". */
+ }

diff --git a/queue-5.10/series b/queue-5.10/series
index bae5c99e88ca442058c7805e3bea174c2394f28c..a243bc71b82e1e4099ab7e10ce0107227b24710e 100644 (file)
--- a/queue-5.10/series
+++ b/queue-5.10/series
@@ -44,3 +44,4 @@ kasan-add-explicit-preconditions-to-kasan_report.patch
 ubsan-implement-__ubsan_handle_alignment_assumption.patch
 revert-lib-restrict-cpumask_local_spread-to-houskeep.patch
 x86-efi-remove-efi-pgd-build-time-checks.patch
+lkdtm-don-t-move-ctors-to-.rodata.patch