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Jack Morgenstein 1f34d8d2e5 net/mlx4_core: Fix reset flow when in command polling mode
[ Upstream commit e15ce4b8d1 ]

As part of unloading a device, the driver switches from
FW command event mode to FW command polling mode.

Part of switching over to polling mode is freeing the command context array
memory (unfortunately, currently, without NULLing the command context array
pointer).

The reset flow calls "complete" to complete all outstanding fw commands
(if we are in event mode). The check for event vs. polling mode here
is to test if the command context array pointer is NULL.

If the reset flow is activated after the switch to polling mode, it will
attempt (incorrectly) to complete all the commands in the context array --
because the pointer was not NULLed when the driver switched over to polling
mode.

As a result, we have a use-after-free situation, which results in a
kernel crash.

For example:
BUG: unable to handle kernel NULL pointer dereference at           (null)
IP: [<ffffffff876c4a8e>] __wake_up_common+0x2e/0x90
PGD 0
Oops: 0000 [#1] SMP
Modules linked in: netconsole nfsv3 nfs_acl nfs lockd grace ...
CPU: 2 PID: 940 Comm: kworker/2:3 Kdump: loaded Not tainted 3.10.0-862.el7.x86_64 #1
Hardware name: Microsoft Corporation Virtual Machine/Virtual Machine, BIOS 090006  04/28/2016
Workqueue: events hv_eject_device_work [pci_hyperv]
task: ffff8d1734ca0fd0 ti: ffff8d17354bc000 task.ti: ffff8d17354bc000
RIP: 0010:[<ffffffff876c4a8e>]  [<ffffffff876c4a8e>] __wake_up_common+0x2e/0x90
RSP: 0018:ffff8d17354bfa38  EFLAGS: 00010082
RAX: 0000000000000000 RBX: ffff8d17362d42c8 RCX: 0000000000000000
RDX: 0000000000000001 RSI: 0000000000000003 RDI: ffff8d17362d42c8
RBP: ffff8d17354bfa70 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000298 R11: ffff8d173610e000 R12: ffff8d17362d42d0
R13: 0000000000000246 R14: 0000000000000000 R15: 0000000000000003
FS:  0000000000000000(0000) GS:ffff8d1802680000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 00000000f16d8000 CR4: 00000000001406e0
Call Trace:
 [<ffffffff876c7adc>] complete+0x3c/0x50
 [<ffffffffc04242f0>] mlx4_cmd_wake_completions+0x70/0x90 [mlx4_core]
 [<ffffffffc041e7b1>] mlx4_enter_error_state+0xe1/0x380 [mlx4_core]
 [<ffffffffc041fa4b>] mlx4_comm_cmd+0x29b/0x360 [mlx4_core]
 [<ffffffffc041ff51>] __mlx4_cmd+0x441/0x920 [mlx4_core]
 [<ffffffff877f62b1>] ? __slab_free+0x81/0x2f0
 [<ffffffff87951384>] ? __radix_tree_lookup+0x84/0xf0
 [<ffffffffc043a8eb>] mlx4_free_mtt_range+0x5b/0xb0 [mlx4_core]
 [<ffffffffc043a957>] mlx4_mtt_cleanup+0x17/0x20 [mlx4_core]
 [<ffffffffc04272c7>] mlx4_free_eq+0xa7/0x1c0 [mlx4_core]
 [<ffffffffc042803e>] mlx4_cleanup_eq_table+0xde/0x130 [mlx4_core]
 [<ffffffffc0433e08>] mlx4_unload_one+0x118/0x300 [mlx4_core]
 [<ffffffffc0434191>] mlx4_remove_one+0x91/0x1f0 [mlx4_core]

The fix is to set the command context array pointer to NULL after freeing
the array.

Fixes: f5aef5aa35 ("net/mlx4_core: Activate reset flow upon fatal command cases")
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Tariq Toukan <tariqt@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-03-19 13:12:40 +01:00
arch perf/x86/intel: Implement support for TSX Force Abort 2019-03-13 14:02:41 -07:00
block blk-iolatency: fix IO hang due to negative inflight counter 2019-03-13 14:02:38 -07:00
certs export.h: remove VMLINUX_SYMBOL() and VMLINUX_SYMBOL_STR() 2018-08-22 23:21:44 +09:00
crypto net: crypto set sk to NULL when af_alg_release. 2019-02-23 09:07:24 +01:00
Documentation dt-bindings: eeprom: at24: add "atmel,24c2048" compatible string 2019-02-20 10:25:35 +01:00
drivers net/mlx4_core: Fix reset flow when in command polling mode 2019-03-19 13:12:40 +01:00
firmware kbuild: remove all dummy assignments to obj- 2017-11-18 11:46:06 +09:00
fs cifs: allow calling SMB2_xxx_free(NULL) 2019-03-13 14:02:40 -07:00
include drm: disable uncached DMA optimization for ARM and arm64 2019-03-13 14:02:40 -07:00
init kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7 2019-01-22 21:40:34 +01:00
ipc ipc/shm.c: use ERR_CAST() for shm_lock() error return 2018-10-05 16:32:04 -07:00
kernel bpf: Fix syscall's stackmap lookup potential deadlock 2019-03-13 14:02:36 -07:00
lib lib/test_kmod.c: potential double free in error handling 2019-03-13 14:02:32 -07:00
LICENSES LICENSES: Remove CC-BY-SA-4.0 license text 2018-10-18 11:28:50 +02:00
mm mm, memory_hotplug: fix off-by-one in is_pageblock_removable 2019-03-13 14:02:32 -07:00
net tcp: handle inet_csk_reqsk_queue_add() failures 2019-03-19 13:12:39 +01:00
samples samples: mei: use /dev/mei0 instead of /dev/mei 2019-02-15 08:10:11 +01:00
scripts scripts/gdb: fix lx-version string output 2019-02-12 19:47:20 +01:00
security apparmor: Fix aa_label_build() error handling for failed merges 2019-03-13 14:02:32 -07:00
sound ASoC: imx-audmux: change snprintf to scnprintf for possible overflow 2019-03-05 17:58:47 +01:00
tools perf trace: Support multiple "vfs_getname" probes 2019-03-13 14:02:37 -07:00
usr initramfs: move gen_initramfs_list.sh from scripts/ to usr/ 2018-08-22 23:21:44 +09:00
virt kvm: fix kvm_ioctl_create_device() reference counting (CVE-2019-6974) 2019-02-12 19:47:25 +01:00
.clang-format clang-format: Set IndentWrappedFunctionNames false 2018-08-01 18:38:51 +02:00
.cocciconfig
.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 libnvdimm-for-4.19_misc 2018-08-25 18:13:10 -07:00
COPYING COPYING: use the new text with points to the license files 2018-03-23 12:41:45 -06:00
CREDITS 9p: remove Ron Minnich from MAINTAINERS 2018-08-17 16:20:26 -07:00
Kbuild Kbuild updates for v4.15 2017-11-17 17:45:29 -08:00
Kconfig kconfig: move the "Executable file formats" menu to fs/Kconfig.binfmt 2018-08-02 08:06:55 +09:00
MAINTAINERS MAINTAINERS: Add Sasha as a stable branch maintainer 2018-12-01 09:37:25 +01:00
Makefile Linux 4.19.29 2019-03-13 14:02:41 -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.