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Filename Latest commit message Latest commit date
Zhang Zhengming bc0905a765 relayfs: fix out-of-bounds access in relay_file_read
[ Upstream commit 43ec16f1450f4936025a9bdf1a273affdb9732c1 ]

There is a crash in relay_file_read, as the var from
point to the end of last subbuf.

The oops looks something like:
pc : __arch_copy_to_user+0x180/0x310
lr : relay_file_read+0x20c/0x2c8
Call trace:
 __arch_copy_to_user+0x180/0x310
 full_proxy_read+0x68/0x98
 vfs_read+0xb0/0x1d0
 ksys_read+0x6c/0xf0
 __arm64_sys_read+0x20/0x28
 el0_svc_common.constprop.3+0x84/0x108
 do_el0_svc+0x74/0x90
 el0_svc+0x1c/0x28
 el0_sync_handler+0x88/0xb0
 el0_sync+0x148/0x180

We get the condition by analyzing the vmcore:

1). The last produced byte and last consumed byte
    both at the end of the last subbuf

2). A softirq calls function(e.g __blk_add_trace)
    to write relay buffer occurs when an program is calling
    relay_file_read_avail().

        relay_file_read
                relay_file_read_avail
                        relay_file_read_consume(buf, 0, 0);
                        //interrupted by softirq who will write subbuf
                        ....
                        return 1;
                //read_start point to the end of the last subbuf
                read_start = relay_file_read_start_pos
                //avail is equal to subsize
                avail = relay_file_read_subbuf_avail
                //from  points to an invalid memory address
                from = buf->start + read_start
                //system is crashed
                copy_to_user(buffer, from, avail)

Link: https://lkml.kernel.org/r/20230419040203.37676-1-zhang.zhengming@h3c.com
Fixes: 8d62fdebda ("relay file read: start-pos fix")
Signed-off-by: Zhang Zhengming <zhang.zhengming@h3c.com>
Reviewed-by: Zhao Lei <zhao_lei1@hoperun.com>
Reviewed-by: Zhou Kete <zhou.kete@h3c.com>
Reviewed-by: Pengcheng Yang <yangpc@wangsu.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-17 11:35:58 +02:00
arch parisc: Fix argument pointer in real64_call_asm() 2023-05-17 11:35:54 +02:00
block blk-iocost: fix divide by 0 error in calc_lcoefs() 2023-03-11 16:43:54 +01:00
certs certs/blacklist_hashes.c: fix const confusion in certs blacklist 2022-06-22 14:11:22 +02:00
crypto crypto: drbg - Only fail when jent is unavailable in FIPS mode 2023-05-17 11:35:42 +02:00
Documentation media: uapi: add MEDIA_BUS_FMT_METADATA_FIXED media bus format. 2023-05-17 11:35:36 +02:00
drivers crypto: safexcel - Cleanup ring IRQ workqueues on load failure 2023-05-17 11:35:58 +02:00
fs btrfs: scrub: reject unsupported scrub flags 2023-05-17 11:35:55 +02:00
include tick/nohz: Fix cpu_is_hotpluggable() by checking with nohz subsystem 2023-05-17 11:35:57 +02:00
init init/Kconfig: fix CC_HAS_ASM_GOTO_TIED_OUTPUT test with dash 2022-12-08 11:22:59 +01:00
ipc ipc/sem: Fix dangling sem_array access in semtimedop race 2022-12-08 11:23:06 +01:00
kernel relayfs: fix out-of-bounds access in relay_file_read 2023-05-17 11:35:58 +02:00
lib debugobject: Ensure pool refill (again) 2023-05-17 11:35:56 +02:00
LICENSES
mm mm/swap: fix swap_info_struct race between swapoff and get_swap_pages() 2023-04-20 12:07:35 +02:00
net netfilter: nf_tables: deactivate anonymous set from preparation phase 2023-05-17 11:35:57 +02:00
samples samples: vfio-mdev: Fix missing pci_disable_device() in mdpy_fb_probe() 2023-01-18 11:41:26 +01:00
scripts scripts/gdb: fix lx-timerlist for Python3 2023-05-17 11:35:55 +02:00
security selinux: ensure av_permissions.h is built when needed 2023-05-17 11:35:34 +02:00
sound ASoC: es8316: Handle optional IRQ assignment 2023-05-17 11:35:46 +02:00
tools perf intel-pt: Fix CYC timestamps after standalone CBR 2023-05-17 11:35:56 +02:00
usr
virt KVM: Destroy target device if coalesced MMIO unregistration fails 2023-03-11 16:44:01 +01:00
.clang-format
.cocciconfig
.get_maintainer.ignore
.gitattributes
.gitignore
.mailmap
COPYING
CREDITS
Kbuild
Kconfig
MAINTAINERS net/phy/mdio-i2c: Move header file to include/linux/mdio 2023-02-06 07:52:46 +01:00
Makefile Linux 5.4.242 2023-04-26 11:24:06 +02:00
README

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.

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.