The commit 8844618d8aa7 ("ext4: only look at the bg_flags field if it
is valid") introduced an issue which are seeing when running "adb
remount" on Android devices with the affected kernels. This change
appears on 4.4.y and later.
> EXT4-fs error (device vdd): ext4_has_uninit_itable:2882: comm remount svc 50: Inode table for bg 0 marked as needing zeroing
> Kernel panic - not syncing: EXT4-fs (device vdd): panic forced after error
Looks like this fix was already picked up for 4.14.y, 4.17.y but
(AFAIK) it isn't on anybody's radar for 4.4 and 4.9. Thanks!
The patch titled
Subject: drivers/block/zram/zram_drv.c: fix bug storing backing_dev
has been added to the -mm tree. Its filename is
zram-fix-bug-storing-backing_dev.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/zram-fix-bug-storing-backing_dev.p…
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/zram-fix-bug-storing-backing_dev.p…
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Peter Kalauskas <peskal(a)google.com>
Subject: drivers/block/zram/zram_drv.c: fix bug storing backing_dev
The call to strlcpy in backing_dev_store is incorrect. It should take
the size of the destination buffer instead of the size of the source
buffer. Additionally, ignore the newline character (\n) when reading
the new file_name buffer. This makes it possible to set the backing_dev
as follows:
echo /dev/sdX > /sys/block/zram0/backing_dev
The reason it worked before was the fact that strlcpy() copies 'len - 1'
bytes, which is strlen(buf) - 1 in our case, so it accidentally didn't
copy the trailing new line symbol. Which also means that "echo -n
/dev/sdX" most likely was broken.
Signed-off-by: Peter Kalauskas <peskal(a)google.com>
Link: http://lkml.kernel.org/r/20180813061623.GC64836@rodete-desktop-imager.corp.…
Acked-by: Minchan Kim <minchan(a)kernel.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky(a)gmail.com>
Cc: <stable(a)vger.kernel.org> [4.14+]
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
---
drivers/block/zram/zram_drv.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
--- a/drivers/block/zram/zram_drv.c~zram-fix-bug-storing-backing_dev
+++ a/drivers/block/zram/zram_drv.c
@@ -337,6 +337,7 @@ static ssize_t backing_dev_store(struct
struct device_attribute *attr, const char *buf, size_t len)
{
char *file_name;
+ size_t sz;
struct file *backing_dev = NULL;
struct inode *inode;
struct address_space *mapping;
@@ -357,7 +358,11 @@ static ssize_t backing_dev_store(struct
goto out;
}
- strlcpy(file_name, buf, len);
+ strlcpy(file_name, buf, PATH_MAX);
+ /* ignore trailing newline */
+ sz = strlen(file_name);
+ if (sz > 0 && file_name[sz - 1] == '\n')
+ file_name[sz - 1] = 0x00;
backing_dev = filp_open(file_name, O_RDWR|O_LARGEFILE, 0);
if (IS_ERR(backing_dev)) {
_
Patches currently in -mm which might be from peskal(a)google.com are
zram-fix-bug-storing-backing_dev.patch
These patches are needed for kasan+clang support. I confirmed they
apply cleanly in order (top to bottom):
4.9:
commit c5caf21ab0cf8 ("kasan: turn on -fsanitize-address-use-after-scope")
commit 0e410e158e5b ("kasan: don't emit builtin calls when sanitization is off")
4.4:
commit c5caf21ab0cf8 ("kasan: turn on -fsanitize-address-use-after-scope")
===
0e410e158e5b is the one I'm interested in. Looks like it landed in
4.16, and got backported to 4.14-stable.
===
c5caf21ab0cf8 depends on c6d308534aef6 ("UBSAN: run-time undefined
behavior sanity checker"), and I don't want to bring in all of UBSAN
to 4.4. I'll send a patch for 0e410e158e5b.
--
Thanks,
~Nick Desaulniers
The function has an inline "return false;" definition with CONFIG_SMP=n but the
"real" definition is also visible leading to "redefinition of
‘apic_id_is_primary_thread’" compiler error. Guard it with #ifdef CONFIG_SMP
Signed-off-by: Vlastimil Babka <vbabka(a)suse.cz>
Fixes: 6a4d2657e048 ("x86/smp: Provide topology_is_primary_thread()")
Cc: stable(a)vger.kernel.org
---
arch/x86/kernel/apic/apic.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 87ff6235bbfe..84132eddb5a8 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -2193,6 +2193,7 @@ static int cpuid_to_apicid[] = {
[0 ... NR_CPUS - 1] = -1,
};
+#ifdef CONFIG_SMP
/**
* apic_id_is_primary_thread - Check whether APIC ID belongs to a primary thread
* @id: APIC ID to check
@@ -2207,6 +2208,7 @@ bool apic_id_is_primary_thread(unsigned int apicid)
mask = (1U << (fls(smp_num_siblings) - 1)) - 1;
return !(apicid & mask);
}
+#endif
/*
* Should use this API to allocate logical CPU IDs to keep nr_logical_cpuids
--
2.18.0
From: Andrey Konovalov <andreyknvl(a)google.com>
commit 0e410e158e5baa1300bdf678cea4f4e0cf9d8b94 upstream.
With KASAN enabled the kernel has two different memset() functions, one
with KASAN checks (memset) and one without (__memset). KASAN uses some
macro tricks to use the proper version where required. For example
memset() calls in mm/slub.c are without KASAN checks, since they operate
on poisoned slab object metadata.
The issue is that clang emits memset() calls even when there is no
memset() in the source code. They get linked with improper memset()
implementation and the kernel fails to boot due to a huge amount of KASAN
reports during early boot stages.
The solution is to add -fno-builtin flag for files with KASAN_SANITIZE :=
n marker.
Link: http://lkml.kernel.org/r/8ffecfffe04088c52c42b92739c2bd8a0bcb3f5e.151638459…
Signed-off-by: Andrey Konovalov <andreyknvl(a)google.com>
Acked-by: Nick Desaulniers <ndesaulniers(a)google.com>
Cc: Masahiro Yamada <yamada.masahiro(a)socionext.com>
Cc: Michal Marek <michal.lkml(a)markovi.net>
Cc: Andrey Ryabinin <aryabinin(a)virtuozzo.com>
Cc: Alexander Potapenko <glider(a)google.com>
Cc: Dmitry Vyukov <dvyukov(a)google.com>
Cc: <stable(a)vger.kernel.org>
Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds(a)linux-foundation.org>
[ Nick : Backported to 4.4 avoiding KUBSAN ]
Signed-off-by: Nick Desaulniers <ndesaulniers(a)google.com>
---
Makefile | 3 ++-
scripts/Makefile.kasan | 3 +++
scripts/Makefile.lib | 2 +-
3 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/Makefile b/Makefile
index ee92a12e3a4b..4fdd43dd14aa 100644
--- a/Makefile
+++ b/Makefile
@@ -418,7 +418,8 @@ export MAKE AWK GENKSYMS INSTALLKERNEL PERL PYTHON UTS_MACHINE
export HOSTCXX HOSTCXXFLAGS LDFLAGS_MODULE CHECK CHECKFLAGS
export KBUILD_CPPFLAGS NOSTDINC_FLAGS LINUXINCLUDE OBJCOPYFLAGS LDFLAGS
-export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV CFLAGS_KASAN
+export KBUILD_CFLAGS CFLAGS_KERNEL CFLAGS_MODULE CFLAGS_GCOV
+export CFLAGS_KASAN CFLAGS_KASAN_NOSANITIZE
export KBUILD_AFLAGS AFLAGS_KERNEL AFLAGS_MODULE
export KBUILD_AFLAGS_MODULE KBUILD_CFLAGS_MODULE KBUILD_LDFLAGS_MODULE
export KBUILD_AFLAGS_KERNEL KBUILD_CFLAGS_KERNEL
diff --git a/scripts/Makefile.kasan b/scripts/Makefile.kasan
index 37323b0df374..2624d4bf9a45 100644
--- a/scripts/Makefile.kasan
+++ b/scripts/Makefile.kasan
@@ -28,4 +28,7 @@ else
CFLAGS_KASAN := $(CFLAGS_KASAN_MINIMAL)
endif
endif
+
+CFLAGS_KASAN_NOSANITIZE := -fno-builtin
+
endif
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 24914e7de944..a2d0e6d32659 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -126,7 +126,7 @@ endif
ifeq ($(CONFIG_KASAN),y)
_c_flags += $(if $(patsubst n%,, \
$(KASAN_SANITIZE_$(basetarget).o)$(KASAN_SANITIZE)y), \
- $(CFLAGS_KASAN))
+ $(CFLAGS_KASAN), $(CFLAGS_KASAN_NOSANITIZE))
endif
# If building the kernel in a separate objtree expand all occurrences
--
2.18.0.865.gffc8e1a3cd6-goog
These are already defined higher up in the file.
Cc: stable(a)vger.kernel.org
Signed-off-by: Josh Poimboeuf <jpoimboe(a)redhat.com>
---
arch/x86/kvm/vmx.c | 3 ---
1 file changed, 3 deletions(-)
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 58bba7a7572a..e7691e666479 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -9725,9 +9725,6 @@ static int vmx_handle_exit(struct kvm_vcpu *vcpu)
* information but as all relevant affected CPUs have 32KiB L1D cache size
* there is no point in doing so.
*/
-#define L1D_CACHE_ORDER 4
-static void *vmx_l1d_flush_pages;
-
static void vmx_l1d_flush(struct kvm_vcpu *vcpu)
{
int size = PAGE_SIZE << L1D_CACHE_ORDER;
--
2.17.1