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Jia-Ju Bai a7bee9598a usb: dwc2: fix possible NULL pointer dereference caused by driver concurrency
[ Upstream commit ef307bc6ef ]

In _dwc2_hcd_urb_enqueue(), "urb->hcpriv = NULL" is executed without
holding the lock "hsotg->lock". In _dwc2_hcd_urb_dequeue():

    spin_lock_irqsave(&hsotg->lock, flags);
    ...
	if (!urb->hcpriv) {
		dev_dbg(hsotg->dev, "## urb->hcpriv is NULL ##\n");
		goto out;
	}
    rc = dwc2_hcd_urb_dequeue(hsotg, urb->hcpriv); // Use urb->hcpriv
    ...
out:
    spin_unlock_irqrestore(&hsotg->lock, flags);

When _dwc2_hcd_urb_enqueue() and _dwc2_hcd_urb_dequeue() are
concurrently executed, the NULL check of "urb->hcpriv" can be executed
before "urb->hcpriv = NULL". After urb->hcpriv is NULL, it can be used
in the function call to dwc2_hcd_urb_dequeue(), which can cause a NULL
pointer dereference.

This possible bug is found by an experimental static analysis tool
developed by myself. This tool analyzes the locking APIs to extract
function pairs that can be concurrently executed, and then analyzes the
instructions in the paired functions to identify possible concurrency
bugs including data races and atomicity violations. The above possible
bug is reported, when my tool analyzes the source code of Linux 6.5.

To fix this possible bug, "urb->hcpriv = NULL" should be executed with
holding the lock "hsotg->lock". After using this patch, my tool never
reports the possible bug, with the kernelconfiguration allyesconfig for
x86_64. Because I have no associated hardware, I cannot test the patch
in runtime testing, and just verify it according to the code logic.

Fixes: 33ad261aa6 ("usb: dwc2: host: spinlock urb_enqueue")
Signed-off-by: Jia-Ju Bai <baijiaju@buaa.edu.cn>
Link: https://lore.kernel.org/r/20230926024404.832096-1-baijiaju@buaa.edu.cn
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-20 11:59:26 +01:00
arch sh: bios: Revive earlyprintk support 2023-11-20 11:59:22 +01:00
block blk-throttle: check for overflow in calculate_bytes_allowed 2023-10-20 18:38:17 -06:00
certs certs: Reference revocation list for all keyrings 2023-08-17 20:12:41 +00:00
crypto certs: Break circular dependency when selftest is modular 2023-11-20 11:59:23 +01:00
Documentation dt-bindings: mfd: mt6397: Split out compatible for MediaTek MT6366 PMIC 2023-11-20 11:59:24 +01:00
drivers usb: dwc2: fix possible NULL pointer dereference caused by driver concurrency 2023-11-20 11:59:26 +01:00
fs f2fs: fix to drop meta_inode's page cache in f2fs_put_super() 2023-11-20 11:59:25 +01:00
include mfd: core: Un-constify mfd_cell.of_reg 2023-11-20 11:59:23 +01:00
init workqueue: Changes for v6.6 2023-09-01 16:06:32 -07:00
io_uring io_uring/kbuf: Allow the full buffer id space for provided buffers 2023-11-20 11:59:11 +01:00
ipc Add x86 shadow stack support 2023-08-31 12:20:12 -07:00
kernel livepatch: Fix missing newline character in klp_resolve_symbols() 2023-11-20 11:59:25 +01:00
lib kunit: test: Fix the possible memory leak in executor_test 2023-11-20 11:59:15 +01:00
LICENSES LICENSES: Add the copyleft-next-0.3.1 license 2022-11-08 15:44:01 +01:00
mm vfs: fix readahead(2) on block devices 2023-11-20 11:58:52 +01:00
net ipv6: avoid atomic fragment on GSO packets 2023-11-20 11:59:03 +01:00
rust rust: docs: fix logo replacement 2023-10-19 16:40:00 +02:00
samples VFIO updates for v6.6-rc1 2023-08-30 20:36:01 -07:00
scripts scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n 2023-11-20 11:59:24 +01:00
security apparmor: fix invalid reference on profile->disconnected 2023-11-20 11:59:24 +01:00
sound ASoC: ams-delta.c: use component after check 2023-11-20 11:59:23 +01:00
tools perf record: Fix BTF type checks in the off-cpu profiling 2023-11-20 11:59:25 +01:00
usr initramfs: Encode dependency on KBUILD_BUILD_TIMESTAMP 2023-06-06 17:54:49 +09:00
virt ARM: 2023-09-07 13:52:20 -07:00
.clang-format iommu: Add for_each_group_device() 2023-05-23 08:15:51 +02:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes .gitattributes: set diff driver for Rust source code files 2023-05-31 17:48:25 +02:00
.gitignore kbuild: rpm-pkg: rename binkernel.spec to kernel.spec 2023-07-25 00:59:33 +09:00
.mailmap 20 hotfixes. 12 are cc:stable and the remainder address post-6.5 issues 2023-10-24 09:52:16 -10:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING
CREDITS USB: Remove Wireless USB and UWB documentation 2023-08-09 14:17:32 +02:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS Char/Misc driver fixes for 6.6-final 2023-10-28 07:51:27 -10:00
Makefile Linux 6.6.1 2023-11-08 11:56:25 +01:00
README

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

There are several guides for kernel developers and users. These guides can
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    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
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Please read the Documentation/process/changes.rst file, as it contains the
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the problems which may result by upgrading your kernel.