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Zhihao Cheng 0c261ca281 ubifs: ubifs_tnc_start_commit: Fix OOB in layout_in_gaps
[ Upstream commit 6abf572621 ]

Running stress-test test_2 in mtd-utils on ubi device, sometimes we can
get following oops message:

  BUG: unable to handle page fault for address: ffffffff00000140
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 280a067 P4D 280a067 PUD 0
  Oops: 0000 [#1] SMP
  CPU: 0 PID: 60 Comm: kworker/u16:1 Kdump: loaded Not tainted 5.2.0 #13
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0
  -0-ga698c8995f-prebuilt.qemu.org 04/01/2014
  Workqueue: writeback wb_workfn (flush-ubifs_0_0)
  RIP: 0010:rb_next_postorder+0x2e/0xb0
  Code: 80 db 03 01 48 85 ff 0f 84 97 00 00 00 48 8b 17 48 83 05 bc 80 db
  03 01 48 83 e2 fc 0f 84 82 00 00 00 48 83 05 b2 80 db 03 01 <48> 3b 7a
  10 48 89 d0 74 02 f3 c3 48 8b 52 08 48 83 05 a3 80 db 03
  RSP: 0018:ffffc90000887758 EFLAGS: 00010202
  RAX: ffff888129ae4700 RBX: ffff888138b08400 RCX: 0000000080800001
  RDX: ffffffff00000130 RSI: 0000000080800024 RDI: ffff888138b08400
  RBP: ffff888138b08400 R08: ffffea0004a6b920 R09: 0000000000000000
  R10: ffffc90000887740 R11: 0000000000000001 R12: ffff888128d48000
  R13: 0000000000000800 R14: 000000000000011e R15: 00000000000007c8
  FS:  0000000000000000(0000) GS:ffff88813ba00000(0000)
  knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: ffffffff00000140 CR3: 000000013789d000 CR4: 00000000000006f0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
    destroy_old_idx+0x5d/0xa0 [ubifs]
    ubifs_tnc_start_commit+0x4fe/0x1380 [ubifs]
    do_commit+0x3eb/0x830 [ubifs]
    ubifs_run_commit+0xdc/0x1c0 [ubifs]

Above Oops are due to the slab-out-of-bounds happened in do-while of
function layout_in_gaps indirectly called by ubifs_tnc_start_commit. In
function layout_in_gaps, there is a do-while loop placing index nodes
into the gaps created by obsolete index nodes in non-empty index LEBs
until rest index nodes can totally be placed into pre-allocated empty
LEBs. @c->gap_lebs points to a memory area(integer array) which records
LEB numbers used by 'in-the-gaps' method. Whenever a fitable index LEB
is found, corresponding lnum will be incrementally written into the
memory area pointed by @c->gap_lebs. The size
((@c->lst.idx_lebs + 1) * sizeof(int)) of memory area is allocated before
do-while loop and can not be changed in the loop. But @c->lst.idx_lebs
could be increased by function ubifs_change_lp (called by
layout_leb_in_gaps->ubifs_find_dirty_idx_leb->get_idx_gc_leb) during the
loop. So, sometimes oob happens when number of cycles in do-while loop
exceeds the original value of @c->lst.idx_lebs. See detail in
https://bugzilla.kernel.org/show_bug.cgi?id=204229.
This patch fixes oob in layout_in_gaps.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2020-01-09 10:20:06 +01:00
Documentation dt-bindings: clock: renesas: rcar-usb2-clock-sel: Fix typo in example 2020-01-09 10:20:05 +01:00
LICENSES LICENSES: Rename other to deprecated 2019-05-03 06:34:32 -06:00
arch arm64: dts: meson: odroid-c2: Disable usb_otg bus to avoid power failed warning 2020-01-09 10:20:05 +01:00
block compat_ioctl: block: handle BLKGETZONESZ/BLKGETNRZONES 2020-01-09 10:19:58 +01:00
certs PKCS#7: Refactor verify_pkcs7_signature() 2019-08-05 18:40:18 -04:00
crypto KEYS: asymmetric: return ENOMEM if akcipher_request_alloc() fails 2019-12-31 16:46:07 +01:00
drivers net: add annotations on hh->hh_len lockless accesses 2020-01-09 10:20:06 +01:00
fs ubifs: ubifs_tnc_start_commit: Fix OOB in layout_in_gaps 2020-01-09 10:20:06 +01:00
include net: add annotations on hh->hh_len lockless accesses 2020-01-09 10:20:06 +01:00
init Merge branch 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-09-28 08:14:15 -07:00
ipc ipc/sem.c: convert to use built-in RCU list checking 2019-09-25 17:51:41 -07:00
kernel kernel/module.c: wakeup processes in module_wq on module unload 2020-01-09 10:20:02 +01:00
lib ubsan, x86: Annotate and allow __ubsan_handle_shift_out_of_bounds() in uaccess regions 2019-12-31 16:44:25 +01:00
mm arm64: Revert support for execute-only user mappings 2020-01-09 10:20:01 +01:00
net net: add annotations on hh->hh_len lockless accesses 2020-01-09 10:20:06 +01:00
samples samples/trace_printk: Wait for IRQ work to finish 2020-01-09 10:20:00 +01:00
scripts gcc-plugins: make it possible to disable CONFIG_GCC_PLUGINS again 2020-01-09 10:19:57 +01:00
security apparmor: fix aa_xattrs_match() may sleep while holding a RCU lock 2020-01-09 10:20:00 +01:00
sound ALSA: firewire-motu: Correct a typo in the clock proc string 2020-01-09 10:20:01 +01:00
tools perf callchain: Fix segfault in thread__resolve_callchain_sample() 2020-01-09 10:20:02 +01:00
usr gen_initramfs_list.sh: fix 'bad variable name' error 2020-01-09 10:20:00 +01:00
virt KVM: arm/arm64: Properly handle faulting of device mappings 2019-12-31 16:46:24 +01:00
.clang-format clang-format: Update with the latest for_each macro list 2019-08-31 10:00:51 +02:00
.cocciconfig
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.mailmap ARM: SoC fixes 2019-11-10 13:41:59 -08:00
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MAINTAINERS Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2019-11-22 14:28:14 -08:00
Makefile Linux 5.4.8 2020-01-04 19:19:19 +01:00
README Drop all 00-INDEX files from Documentation/ 2018-09-09 15:08:58 -06:00

README

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

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

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