Messages in this thread | | | Subject | Re: [PATCH] USB: serial: Fix possible memleak in keyspan_port_probe() | From | "wanghai (M)" <> | Date | Fri, 15 Oct 2021 15:12:27 +0800 |
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在 2021/10/14 22:11, Johan Hovold 写道: > On Thu, Oct 14, 2021 at 09:20:33PM +0800, Wang Hai wrote: >> I got memory leak as follows when doing fault injection test: >> >> unreferenced object 0xffff888258228440 (size 64): >> comm "kworker/7:2", pid 2005, jiffies 4294989509 (age 824.540s) >> hex dump (first 32 bytes): >> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >> 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >> backtrace: >> [<ffffffff8167939c>] slab_post_alloc_hook+0x9c/0x490 >> [<ffffffff8167f627>] kmem_cache_alloc_trace+0x1f7/0x470 >> [<ffffffffa02ac0e4>] keyspan_port_probe+0xa4/0x5d0 [keyspan] >> [<ffffffffa0294c07>] usb_serial_device_probe+0x97/0x1d0 [usbserial] >> [<ffffffff82b50ca7>] really_probe+0x167/0x460 >> [<ffffffff82b51099>] __driver_probe_device+0xf9/0x180 >> [<ffffffff82b51173>] driver_probe_device+0x53/0x130 >> [<ffffffff82b516f5>] __device_attach_driver+0x105/0x130 >> [<ffffffff82b4cfe9>] bus_for_each_drv+0x129/0x190 >> [<ffffffff82b50a69>] __device_attach+0x1c9/0x270 >> [<ffffffff82b518d0>] device_initial_probe+0x20/0x30 >> [<ffffffff82b4f062>] bus_probe_device+0x142/0x160 >> [<ffffffff82b4a4e9>] device_add+0x829/0x1300 >> [<ffffffffa0295fda>] usb_serial_probe.cold+0xc9b/0x14ac [usbserial] >> [<ffffffffa02266aa>] usb_probe_interface+0x1aa/0x3c0 [usbcore] >> [<ffffffff82b50ca7>] really_probe+0x167/0x460 >> >> If it fails to allocate memory for an out_buffer[i] or in_buffer[i], >> the previously allocated memory for out_buffer or in_buffer needs to >> be freed on the error handling path, otherwise a memory leak will result. >> >> Fixes: bad41a5bf177 ("USB: keyspan: fix port DMA-buffer allocations") >> Reported-by: Hulk Robot <hulkci@huawei.com> >> Signed-off-by: Wang Hai <wanghai38@huawei.com> >> --- >> drivers/usb/serial/keyspan.c | 7 +++---- >> 1 file changed, 3 insertions(+), 4 deletions(-) >> >> diff --git a/drivers/usb/serial/keyspan.c b/drivers/usb/serial/keyspan.c >> index 87b89c99d517..ba27a9f0275b 100644 >> --- a/drivers/usb/serial/keyspan.c >> +++ b/drivers/usb/serial/keyspan.c >> @@ -2901,7 +2901,7 @@ static int keyspan_port_probe(struct usb_serial_port *port) >> >> p_priv->inack_buffer = kzalloc(INACK_BUFLEN, GFP_KERNEL); >> if (!p_priv->inack_buffer) >> - goto err_inack_buffer; >> + goto err_out_buffer; >> >> p_priv->outcont_buffer = kzalloc(OUTCONT_BUFLEN, GFP_KERNEL); >> if (!p_priv->outcont_buffer) >> @@ -2953,13 +2953,12 @@ static int keyspan_port_probe(struct usb_serial_port *port) >> >> err_outcont_buffer: >> kfree(p_priv->inack_buffer); >> -err_inack_buffer: >> +err_out_buffer: >> for (i = 0; i < ARRAY_SIZE(p_priv->out_buffer); ++i) >> kfree(p_priv->out_buffer[i]); >> -err_out_buffer: >> +err_in_buffer: >> for (i = 0; i < ARRAY_SIZE(p_priv->in_buffer); ++i) >> kfree(p_priv->in_buffer[i]); >> -err_in_buffer: >> kfree(p_priv); >> >> return -ENOMEM; > Good catch. Fortunately these small allocations would currently never > fail, but we should fix it up nonetheless. > > The fix looks correct, but you're now mixing two styles of error labels > (i.e. naming them after where you jump from and after what they do, > respectively). > > Since you're touching all but one label, could you rename also the last > one after what is done and include a "free_" infix in the label names > (e.g. err_free_in_buffer, etc)? Okay, thank you for your suggestion, I will send the v2 patch. > > Johan > . > -- Wang Hai
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