Minimal supplement to upstream Kernel Self Protection Project changes. Features already provided by SELinux + Yama and archs other than multiarch arm64 / x86_64 aren't in scope. Only tags have stable history. Shared IRC channel with KSPP: irc.libera.chat #linux-hardening
Find a file
Chao Yu d3f07c049d f2fs: fix invalid memory access
syzbot found the following crash on:

HEAD commit:    d9bd94c0bcaa Add linux-next specific files for 20180801
git tree:       linux-next
console output: https://syzkaller.appspot.com/x/log.txt?x=1001189c400000
kernel config:  https://syzkaller.appspot.com/x/.config?x=cc8964ea4d04518c
dashboard link: https://syzkaller.appspot.com/bug?extid=c966a82db0b14aa37e81
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+c966a82db0b14aa37e81@syzkaller.appspotmail.com

loop7: rw=12288, want=8200, limit=20
netlink: 65342 bytes leftover after parsing attributes in process `syz-executor4'.
openvswitch: netlink: Message has 8 unknown bytes.
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN
CPU: 1 PID: 7615 Comm: syz-executor7 Not tainted 4.18.0-rc7-next-20180801+ #29
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:142 [inline]
RIP: 0010:PageLocked include/linux/page-flags.h:272 [inline]
RIP: 0010:f2fs_put_page fs/f2fs/f2fs.h:2011 [inline]
RIP: 0010:validate_checkpoint+0x66d/0xec0 fs/f2fs/checkpoint.c:835
Code: e8 58 05 7f fe 4c 8d 6b 80 4d 8d 74 24 08 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 c6 04 02 00 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 f4 06 00 00 4c 89 ea 4d 8b 7c 24 08 48 b8 00 00
RSP: 0018:ffff8801937cebe8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff8801937cef30 RCX: ffffc90006035000
RDX: 0000000000000000 RSI: ffffffff82fd9658 RDI: 0000000000000005
RBP: ffff8801937cef58 R08: ffff8801ab254700 R09: fffff94000d9e026
R10: fffff94000d9e026 R11: ffffea0006cf0137 R12: fffffffffffffffb
R13: ffff8801937ceeb0 R14: 0000000000000003 R15: ffff880193419b40
FS:  00007f36a61d5700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc04ff93000 CR3: 00000001d0562000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 f2fs_get_valid_checkpoint+0x436/0x1ec0 fs/f2fs/checkpoint.c:860
 f2fs_fill_super+0x2d42/0x8110 fs/f2fs/super.c:2883
 mount_bdev+0x314/0x3e0 fs/super.c:1344
 f2fs_mount+0x3c/0x50 fs/f2fs/super.c:3133
 legacy_get_tree+0x131/0x460 fs/fs_context.c:729
 vfs_get_tree+0x1cb/0x5c0 fs/super.c:1743
 do_new_mount fs/namespace.c:2603 [inline]
 do_mount+0x6f2/0x1e20 fs/namespace.c:2927
 ksys_mount+0x12d/0x140 fs/namespace.c:3143
 __do_sys_mount fs/namespace.c:3157 [inline]
 __se_sys_mount fs/namespace.c:3154 [inline]
 __x64_sys_mount+0xbe/0x150 fs/namespace.c:3154
 do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x45943a
Code: b8 a6 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 bd 8a fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 0f 83 9a 8a fb ff c3 66 0f 1f 84 00 00 00 00 00
RSP: 002b:00007f36a61d4a88 EFLAGS: 00000206 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f36a61d4b30 RCX: 000000000045943a
RDX: 00007f36a61d4ad0 RSI: 0000000020000100 RDI: 00007f36a61d4af0
RBP: 0000000020000100 R08: 00007f36a61d4b30 R09: 00007f36a61d4ad0
R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000013
R13: 0000000000000000 R14: 00000000004c8ea0 R15: 0000000000000000
Modules linked in:
Dumping ftrace buffer:
   (ftrace buffer empty)
---[ end trace bd8550c129352286 ]---
RIP: 0010:__read_once_size include/linux/compiler.h:188 [inline]
RIP: 0010:compound_head include/linux/page-flags.h:142 [inline]
RIP: 0010:PageLocked include/linux/page-flags.h:272 [inline]
RIP: 0010:f2fs_put_page fs/f2fs/f2fs.h:2011 [inline]
RIP: 0010:validate_checkpoint+0x66d/0xec0 fs/f2fs/checkpoint.c:835
Code: e8 58 05 7f fe 4c 8d 6b 80 4d 8d 74 24 08 48 b8 00 00 00 00 00 fc ff df 4c 89 ea 48 c1 ea 03 c6 04 02 00 4c 89 f2 48 c1 ea 03 <80> 3c 02 00 0f 85 f4 06 00 00 4c 89 ea 4d 8b 7c 24 08 48 b8 00 00
RSP: 0018:ffff8801937cebe8 EFLAGS: 00010246
RAX: dffffc0000000000 RBX: ffff8801937cef30 RCX: ffffc90006035000
RDX: 0000000000000000 RSI: ffffffff82fd9658 RDI: 0000000000000005
netlink: 65342 bytes leftover after parsing attributes in process `syz-executor4'.
RBP: ffff8801937cef58 R08: ffff8801ab254700 R09: fffff94000d9e026
openvswitch: netlink: Message has 8 unknown bytes.
R10: fffff94000d9e026 R11: ffffea0006cf0137 R12: fffffffffffffffb
R13: ffff8801937ceeb0 R14: 0000000000000003 R15: ffff880193419b40
FS:  00007f36a61d5700(0000) GS:ffff8801db100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc04ff93000 CR3: 00000001d0562000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

In validate_checkpoint(), if we failed to call get_checkpoint_version(), we
will pass returned invalid page pointer into f2fs_put_page, cause accessing
invalid memory, this patch tries to handle error path correctly to fix this
issue.

Signed-off-by: Chao Yu <yuchao0@huawei.com>

Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2018-08-10 16:19:05 -07:00
arch Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2018-07-06 09:14:34 -07:00
block for-linus-20180629 2018-06-30 10:47:46 -07:00
certs certs/blacklist: fix const confusion 2018-06-26 09:43:03 -07:00
crypto Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
Documentation USB fixes for 4.18-rc3 2018-07-01 11:50:16 -07:00
drivers Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux 2018-07-06 09:14:34 -07:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs f2fs: fix invalid memory access 2018-08-10 16:19:05 -07:00
include f2fs: Allocate and stat mem used by free nid bitmap more accurately 2018-07-28 18:23:26 -07:00
init Kbuild fixes for v4.18 2018-06-30 13:05:30 -07:00
ipc ipc: use new return type vm_fault_t 2018-06-15 07:55:25 +09:00
kernel While cleaning out my INBOX, I found a few patches that were lost 2018-07-05 19:29:07 -07:00
lib Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
LICENSES LICENSES: Add Linux-OpenIB license text 2018-04-27 16:41:53 -06:00
mm mm: teach dump_page() to correctly output poisoned struct pages 2018-07-03 17:32:19 -07:00
net net/smc: fix up merge error with poll changes 2018-07-03 09:53:43 -07:00
samples bpf: Change bpf_fib_lookup to return lookup status 2018-06-29 00:02:02 +02:00
scripts Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
security selinux/stable-4.18 PR 20180629 2018-06-30 11:15:12 -07:00
sound ALSA: seq: Fix UBSAN warning at SNDRV_SEQ_IOCTL_QUERY_NEXT_CLIENT ioctl 2018-06-25 11:18:04 +02:00
tools Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
usr kbuild: rename built-in.o to built-in.a 2018-03-26 02:01:19 +09:00
virt KVM: arm64: Prevent KVM_COMPAT from being selected 2018-06-21 17:17:50 +01:00
.clang-format clang-format: add configuration file 2018-04-11 10:28:35 -07:00
.cocciconfig scripts: add Linux .cocciconfig for coccinelle 2016-07-22 12:13:39 +02:00
.get_maintainer.ignore
.gitattributes .gitattributes: set git diff driver for C source code files 2016-10-07 18:46:30 -07:00
.gitignore Kbuild updates for v4.17 (2nd) 2018-04-15 17:21:30 -07:00
.mailmap Merge branch 'asoc-4.17' into asoc-4.18 for compress dependencies 2018-04-26 12:24:28 +01:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS MAINTAINERS/CREDITS: Drop METAG ARCHITECTURE 2018-03-05 16:34:24 +00:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: add basic helper macros to scripts/Kconfig.include 2018-05-29 03:31:19 +09:00
MAINTAINERS proc: add Alexey to MAINTAINERS 2018-06-28 11:16:44 -07:00
Makefile Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-02 11:18:28 -07:00
README Docs: Added a pointer to the formatted docs to README 2018-03-21 09:02:53 -06:00

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.