[patch added to 3.12-stable] gcov: disable tree-loop-im to reduce stack usage

[patch added to 3.12-stable] gcov: disable tree-loop-im to reduce stack usage

[Jiri Slaby]

From: Arnd Bergmann <arnd@arndb.de>

This patch has been added to the 3.12 stable tree. If you have any
objections, please let us know.

===============

commit c87bf431448b404a6ef5fbabd74c0e3e42157a7f upstream.

Enabling CONFIG_GCOV_PROFILE_ALL produces us a lot of warnings like

lib/lz4/lz4hc_compress.c: In function 'lz4_compresshcctx':
lib/lz4/lz4hc_compress.c:514:1: warning: the frame size of 1504 bytes is larger than 1024 bytes [-Wframe-larger-than=]

After some investigation, I found that this behavior started with gcc-4.9,
and opened https://gcc.gnu.org/bugzilla/show_bug.cgi?id=69702.
A suggested workaround for it is to use the -fno-tree-loop-im
flag that turns off one of the optimization stages in gcc, so the
code runs a little slower but does not use excessive amounts
of stack.

We could make this conditional on the gcc version, but I could not
find an easy way to do this in Kbuild and the benefit would be
fairly small, given that most of the gcc version in production are
affected now.

I'm marking this for 'stable' backports because it addresses a bug
with code generation in gcc that exists in all kernel versions
with the affected gcc releases.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Signed-off-by: Michal Marek <mmarek@suse.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Makefile b/Makefile
index a90b363b3493..4c1baa9b6bae 100644
--- a/Makefile
+++ b/Makefile
@@ -347,7 +347,7 @@ AFLAGS_MODULE   =
 LDFLAGS_MODULE  =
 CFLAGS_KERNEL	=
 AFLAGS_KERNEL	=
-CFLAGS_GCOV	= -fprofile-arcs -ftest-coverage
+CFLAGS_GCOV	= -fprofile-arcs -ftest-coverage -fno-tree-loop-im
 
 
 # Use USERINCLUDE when you must reference the UAPI directories only.
-- 
2.10.1

[patch added to 3.12-stable] reiserfs: fix "new_insert_key may be used uninitialized ..."

[Jiri Slaby]

From: Jeff Mahoney <jeffm@suse.com>

This patch has been added to the 3.12 stable tree. If you have any
objections, please let us know.

===============

commit 0a11b9aae49adf1f952427ef1a1d9e793dd6ffb6 upstream.

new_insert_key only makes any sense when it's associated with a
new_insert_ptr, which is initialized to NULL and changed to a
buffer_head when we also initialize new_insert_key.  We can key off of
that to avoid the uninitialized warning.

Link: http://lkml.kernel.org/r/5eca5ffb-2155-8df2-b4a2-f162f105efed@suse.com
Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jan Kara <jack@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 fs/reiserfs/ibalance.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/fs/reiserfs/ibalance.c b/fs/reiserfs/ibalance.c
index e1978fd895f5..58cce0c606f1 100644
--- a/fs/reiserfs/ibalance.c
+++ b/fs/reiserfs/ibalance.c
@@ -1082,8 +1082,9 @@ int balance_internal(struct tree_balance *tb,	/* tree_balance structure
 				       insert_ptr);
 	}
 
-	memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE);
 	insert_ptr[0] = new_insert_ptr;
+	if (new_insert_ptr)
+		memcpy(new_insert_key_addr, &new_insert_key, KEY_SIZE);
 
 	return order;
 }
-- 
2.10.1

[patch added to 3.12-stable] crypto: skcipher - Fix blkcipher walk OOM crash

[Jiri Slaby]

From: Herbert Xu <herbert@gondor.apana.org.au>

This patch has been added to the 3.12 stable tree. If you have any
objections, please let us know.

===============

commit acdb04d0b36769b3e05990c488dc74d8b7ac8060 upstream.

When we need to allocate a temporary blkcipher_walk_next and it
fails, the code is supposed to take the slow path of processing
the data block by block.  However, due to an unrelated change
we instead end up dereferencing the NULL pointer.

This patch fixes it by moving the unrelated bsize setting out
of the way so that we enter the slow path as inteded.

Fixes: 7607bd8ff03b ("[CRYPTO] blkcipher: Added blkcipher_walk_virt_block")
Reported-by: xiakaixu <xiakaixu@huawei.com>
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
---
 crypto/blkcipher.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/crypto/blkcipher.c b/crypto/blkcipher.c
index a79e7e9ab86e..5e77722a00e7 100644
--- a/crypto/blkcipher.c
+++ b/crypto/blkcipher.c
@@ -238,6 +238,8 @@ static int blkcipher_walk_next(struct blkcipher_desc *desc,
 		return blkcipher_walk_done(desc, walk, -EINVAL);
 	}
 
+	bsize = min(walk->blocksize, n);
+
 	walk->flags &= ~(BLKCIPHER_WALK_SLOW | BLKCIPHER_WALK_COPY |
 			 BLKCIPHER_WALK_DIFF);
 	if (!scatterwalk_aligned(&walk->in, alignmask) ||
@@ -250,7 +252,6 @@ static int blkcipher_walk_next(struct blkcipher_desc *desc,
 		}
 	}
 
-	bsize = min(walk->blocksize, n);
 	n = scatterwalk_clamp(&walk->in, n);
 	n = scatterwalk_clamp(&walk->out, n);
 
-- 
2.10.1