-Wself-assign in drivers/net/usb/lan78xx.c #129

tpimh · 2018-09-20T12:53:00Z

drivers/net/usb/lan78xx.c:952:11: warning: explicitly assigning value of variable
      of type 'u32' (aka 'unsigned int') to itself [-Wself-assign]
                        offset = offset;
                        ~~~~~~ ^ ~~~~~~
1 warning generated.

The text was updated successfully, but these errors were encountered:

nathanchance · 2018-09-20T22:49:05Z

Patch sent: https://lore.kernel.org/lkml/20180920224829.17072-1-natechancellor@gmail.com/

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>

nathanchance · 2018-09-23T19:52:55Z

Patch accepted: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=94e7c844990f0db92418586b107be135b4963b66

nathanchance · 2018-10-25T16:33:17Z

Merged into mainline: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=94e7c844990f0db92418586b107be135b4963b66

Syzbot and KASAN found the following invalid-free bug in port_over_current_notify(): -------------------------------------------------------------------------- BUG: KASAN: double-free or invalid-free in port_over_current_notify drivers/usb/core/hub.c:5192 [inline] BUG: KASAN: double-free or invalid-free in port_event drivers/usb/core/hub.c:5241 [inline] BUG: KASAN: double-free or invalid-free in hub_event+0xd97/0x4140 drivers/usb/core/hub.c:5384 CPU: 1 PID: 32710 Comm: kworker/1:3 Not tainted 4.20.0-rc3+ #129 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Workqueue: usb_hub_wq hub_event Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x244/0x39d lib/dump_stack.c:113 print_address_description.cold.7+0x9/0x1ff mm/kasan/report.c:256 kasan_report_invalid_free+0x64/0xa0 mm/kasan/report.c:336 __kasan_slab_free+0x13a/0x150 mm/kasan/kasan.c:501 kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528 __cache_free mm/slab.c:3498 [inline] kfree+0xcf/0x230 mm/slab.c:3817 port_over_current_notify drivers/usb/core/hub.c:5192 [inline] port_event drivers/usb/core/hub.c:5241 [inline] hub_event+0xd97/0x4140 drivers/usb/core/hub.c:5384 process_one_work+0xc90/0x1c40 kernel/workqueue.c:2153 worker_thread+0x17f/0x1390 kernel/workqueue.c:2296 kthread+0x35a/0x440 kernel/kthread.c:246 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352 -------------------------------------------------------------------------- The problem is caused by use of a static array to store environment-string pointers. When the routine is called by multiple threads concurrently, the pointers from one thread can overwrite those from another. The solution is to use an ordinary automatic array instead of a static array. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: syzbot+98881958e1410ec7e53c@syzkaller.appspotmail.com Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>

Add Synopsys PCIe Endpoint eDMA IP core driver to kernel. This IP is generally distributed with Synopsys PCIe Endpoint IP (depends of the use and licensing agreement). This core driver, initializes and configures the eDMA IP using vma-helpers functions and dma-engine subsystem. This driver can be compile as built-in or external module in kernel. To enable this driver just select DW_EDMA option in kernel configuration, however it requires and selects automatically DMA_ENGINE and DMA_VIRTUAL_CHANNELS option too. In order to transfer data from point A to B as fast as possible this IP requires a dedicated memory space containing linked list of elements. All elements of this linked list are continuous and each one describes a data transfer (source and destination addresses, length and a control variable). For the sake of simplicity, lets assume a memory space for channel write 0 which allows about 42 elements. +---------+ | Desc #0 |-+ +---------+ | V +----------+ | Chunk #0 |-+ | CB = 1 | | +----------+ +-----+ +-----------+ +-----+ +----------+ +->| Burst #0 |->| ... |->| Burst #41 |->| llp | | +----------+ +-----+ +-----------+ +-----+ V +----------+ | Chunk #1 |-+ | CB = 0 | | +-----------+ +-----+ +-----------+ +-----+ +----------+ +->| Burst #42 |->| ... |->| Burst #83 |->| llp | | +-----------+ +-----+ +-----------+ +-----+ V +----------+ | Chunk #2 |-+ | CB = 1 | | +-----------+ +-----+ +------------+ +-----+ +----------+ +->| Burst #84 |->| ... |->| Burst #125 |->| llp | | +-----------+ +-----+ +------------+ +-----+ V +----------+ | Chunk #3 |-+ | CB = 0 | | +------------+ +-----+ +------------+ +-----+ +----------+ +->| Burst #126 |->| ... |->| Burst #129 |->| llp | +------------+ +-----+ +------------+ +-----+ Legend: - Linked list, also know as Chunk - Linked list element*, also know as Burst *CB*, also know as Change Bit, it's a control bit (and typically is toggled) that allows to easily identify and differentiate between the current linked list and the previous or the next one. - LLP, is a special element that indicates the end of the linked list element stream also informs that the next CB should be toggle On every last Burst of the Chunk (Burst #41, Burst #83, Burst #125 or even Burst #129) is set some flags on their control variable (RIE and LIE bits) that will trigger the send of "done" interruption. On the interruptions callback, is decided whether to recycle the linked list memory space by writing a new set of Bursts elements (if still exists Chunks to transfer) or is considered completed (if there is no Chunks available to transfer). On scatter-gather transfer mode, the client will submit a scatter-gather list of n (on this case 130) elements, that will be divide in multiple Chunks, each Chunk will have (on this case 42) a limited number of Bursts and after transferring all Bursts, an interrupt will be triggered, which will allow to recycle the all linked list dedicated memory again with the new information relative to the next Chunk and respective Burst associated and repeat the whole cycle again. On cyclic transfer mode, the client will submit a buffer pointer, length of it and number of repetitions, in this case each burst will correspond directly to each repetition. Each Burst can describes a data transfer from point A(source) to point B(destination) with a length that can be from 1 byte up to 4 GB. Since dedicated the memory space where the linked list will reside is limited, the whole n burst elements will be organized in several Chunks, that will be used later to recycle the dedicated memory space to initiate a new sequence of data transfers. The whole transfer is considered has completed when it was transferred all bursts. Currently this IP has a set well-known register map, which includes support for legacy and unroll modes. Legacy mode is version of this register map that has multiplexer register that allows to switch registers between all write and read channels and the unroll modes repeats all write and read channels registers with an offset between them. This register map is called v0. The IP team is creating a new register map more suitable to the latest PCIe features, that very likely will change the map register, which this version will be called v1. As soon as this new version is released by the IP team the support for this version in be included on this driver. According to the logic, patches 1, 2 and 3 should be squashed into 1 unique patch, but for the sake of simplicity of review, it was divided in this 3 patches files. Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com> Cc: Vinod Koul <vkoul@kernel.org> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Joao Pinto <jpinto@synopsys.com> Signed-off-by: Vinod Koul <vkoul@kernel.org>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Link: https://git.kernel.org/linus/94e7c844990f0db92418586b107be135b4963b66 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Link: https://git.kernel.org/linus/94e7c844990f0db92418586b107be135b4963b66 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: Henrique Pereira <hlcpereira@outlook.com.br>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Link: https://git.kernel.org/linus/94e7c844990f0db92418586b107be135b4963b66 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Change-Id: Ia3037cdcf96bb7e720273bf2050a61d20af14e0a Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Git-commit: 94e7c844990f0db92418586b107be135b4963b66 Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git Signed-off-by: Liangliang Lu <luliang@codeaurora.org> Signed-off-by: Adam W. Willis <return.of.octobot@gmail.com>

commit 94e7c844990f0db92418586b107be135b4963b66 upstream. Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 94e7c84 upstream. Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Link: https://git.kernel.org/linus/94e7c844990f0db92418586b107be135b4963b66 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>

commit 94e7c844990f0db92418586b107be135b4963b66 upstream. Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Link: https://git.kernel.org/linus/94e7c844990f0db92418586b107be135b4963b66 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Change-Id: Ia39a9417b2cca78823906b985c42678fbcaa0278

commit 94e7c844990f0db92418586b107be135b4963b66 upstream. Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Link: https://git.kernel.org/linus/94e7c844990f0db92418586b107be135b4963b66 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Change-Id: Ia39a9417b2cca78823906b985c42678fbcaa0278

commit 94e7c844990f0db92418586b107be135b4963b66 upstream. Clang warns when a variable is assigned to itself. drivers/net/usb/lan78xx.c:940:11: warning: explicitly assigning value of variable of type 'u32' (aka 'unsigned int') to itself [-Wself-assign] offset = offset; ~~~~~~ ^ ~~~~~~ 1 warning generated. Reorder the if statement to acheive the same result and avoid a self assignment warning. Link: ClangBuiltLinux/linux#129 Signed-off-by: Nathan Chancellor <natechancellor@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Anders Roxell <anders.roxell@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tpimh added [BUG] linux A bug that should be fixed in the mainline kernel. low priority This bug is not critical and not a priority labels Sep 20, 2018

nathanchance added the -Wself-assign label Sep 20, 2018

nathanchance self-assigned this Sep 20, 2018

nathanchance added [PATCH] Exists There is a patch that fixes this issue [PATCH] Submitted A patch has been submitted for review and removed [PATCH] Exists There is a patch that fixes this issue labels Sep 20, 2018

nathanchance added [PATCH] Accepted A submitted patch has been accepted upstream and removed [PATCH] Submitted A patch has been submitted for review labels Sep 23, 2018

nathanchance closed this as completed Oct 25, 2018

nathanchance added [FIXED][LINUX] 4.20 This bug was fixed in Linux 4.20 and removed [PATCH] Accepted A submitted patch has been accepted upstream labels Oct 25, 2018

tpimh removed the low priority This bug is not critical and not a priority label Oct 26, 2018

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-Wself-assign in drivers/net/usb/lan78xx.c #129

-Wself-assign in drivers/net/usb/lan78xx.c #129

tpimh commented Sep 20, 2018

nathanchance commented Sep 20, 2018

nathanchance commented Sep 23, 2018

nathanchance commented Oct 25, 2018

-Wself-assign in drivers/net/usb/lan78xx.c #129

-Wself-assign in drivers/net/usb/lan78xx.c #129

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tpimh commented Sep 20, 2018

nathanchance commented Sep 20, 2018

nathanchance commented Sep 23, 2018

nathanchance commented Oct 25, 2018