[packages/kernel/LINUX_4_9] - up to 4.9.49; fix CVE-2017-14340: xfs: unprivileged user kernel oops, too

[arekm]

commit 7379240e5f01c47f57b5063c9ccc0ff704124df3
Author: Arkadiusz Miśkiewicz <arekm at maven.pl>
Date:   Wed Sep 13 11:32:50 2017 +0200

    - up to 4.9.49; fix CVE-2017-14340: xfs: unprivileged user kernel oops, too

 kernel-small_fixes.patch | 66 ++++++++++++++++++++++++++++++++++++++++++++++++
 kernel.spec              |  4 +--
 2 files changed, 68 insertions(+), 2 deletions(-)
---
diff --git a/kernel.spec b/kernel.spec
index ed9ff8c3..f0948849 100644
--- a/kernel.spec
+++ b/kernel.spec
@@ -73,7 +73,7 @@
 
 %define		rel		1
 %define		basever		4.9
-%define		postver		.47
+%define		postver		.49
 
 # define this to '-%{basever}' for longterm branch
 %define		versuffix	-%{basever}
@@ -125,7 +125,7 @@ Source0:	https://www.kernel.org/pub/linux/kernel/v4.x/linux-%{basever}.tar.xz
 # Source0-md5:	0a68ef3615c64bd5ee54a3320e46667d
 %if "%{postver}" != ".0"
 Patch0:		https://www.kernel.org/pub/linux/kernel/v4.x/patch-%{version}.xz
-# Patch0-md5:	b3c2f0a15f538597811e7389bd553f38
+# Patch0-md5:	034e10554bed9724f30f25adc020aecc
 %endif
 Source1:	kernel.sysconfig
 
diff --git a/kernel-small_fixes.patch b/kernel-small_fixes.patch
index 319191ce..46c63695 100644
--- a/kernel-small_fixes.patch
+++ b/kernel-small_fixes.patch
@@ -61,3 +61,69 @@ index 098ce9b179ee..fcf8d0aa66ec 100644
 -- 
 2.11.0
 
+commit b31ff3cdf540110da4572e3e29bd172087af65cc
+Author: Richard Wareing <rwareing at fb.com>
+Date:   Wed Sep 13 09:09:35 2017 +1000
+
+    xfs: XFS_IS_REALTIME_INODE() should be false if no rt device present
+    
+    If using a kernel with CONFIG_XFS_RT=y and we set the RHINHERIT flag on
+    a directory in a filesystem that does not have a realtime device and
+    create a new file in that directory, it gets marked as a real time file.
+    When data is written and a fsync is issued, the filesystem attempts to
+    flush a non-existent rt device during the fsync process.
+    
+    This results in a crash dereferencing a null buftarg pointer in
+    xfs_blkdev_issue_flush():
+    
+      BUG: unable to handle kernel NULL pointer dereference at 0000000000000008
+      IP: xfs_blkdev_issue_flush+0xd/0x20
+      .....
+      Call Trace:
+        xfs_file_fsync+0x188/0x1c0
+        vfs_fsync_range+0x3b/0xa0
+        do_fsync+0x3d/0x70
+        SyS_fsync+0x10/0x20
+        do_syscall_64+0x4d/0xb0
+        entry_SYSCALL64_slow_path+0x25/0x25
+    
+    Setting RT inode flags does not require special privileges so any
+    unprivileged user can cause this oops to occur.  To reproduce, confirm
+    kernel is compiled with CONFIG_XFS_RT=y and run:
+    
+      # mkfs.xfs -f /dev/pmem0
+      # mount /dev/pmem0 /mnt/test
+      # mkdir /mnt/test/foo
+      # xfs_io -c 'chattr +t' /mnt/test/foo
+      # xfs_io -f -c 'pwrite 0 5m' -c fsync /mnt/test/foo/bar
+    
+    Or just run xfstests with MKFS_OPTIONS="-d rtinherit=1" and wait.
+    
+    Kernels built with CONFIG_XFS_RT=n are not exposed to this bug.
+    
+    Fixes: f538d4da8d52 ("[XFS] write barrier support")
+    Cc: <stable at vger.kernel.org>
+    Signed-off-by: Richard Wareing <rwareing at fb.com>
+    Signed-off-by: Dave Chinner <david at fromorbit.com>
+    Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
+
+diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h
+index 9301c5a6060b..dcd1292664b3 100644
+--- a/fs/xfs/xfs_linux.h
++++ b/fs/xfs/xfs_linux.h
+@@ -270,7 +270,14 @@ static inline uint64_t howmany_64(uint64_t x, uint32_t y)
+ #endif /* DEBUG */
+ 
+ #ifdef CONFIG_XFS_RT
+-#define XFS_IS_REALTIME_INODE(ip) ((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME)
++
++/*
++ * make sure we ignore the inode flag if the filesystem doesn't have a
++ * configured realtime device.
++ */
++#define XFS_IS_REALTIME_INODE(ip)			\
++	(((ip)->i_d.di_flags & XFS_DIFLAG_REALTIME) &&	\
++	 (ip)->i_mount->m_rtdev_targp)
+ #else
+ #define XFS_IS_REALTIME_INODE(ip) (0)
+ #endif
================================================================

---- gitweb:

http://git.pld-linux.org/gitweb.cgi/packages/kernel.git/commitdiff/7379240e5f01c47f57b5063c9ccc0ff704124df3