On Thu, Mar 10, 2022 at 10:51:42AM +0100, Oliver Neukum wrote: > > On 10.03.22 00:54, syzbot wrote: > > > Hello, > > > > syzbot found the following issue on: > > > > HEAD commit: 0014404f9c18 Merge branch 'akpm' (patches from Andrew) > > git tree: upstream > > console output: https://syzkaller.appspot.com/x/log.txt?x=15864216700000 > > kernel config: https://syzkaller.appspot.com/x/.config?x=3f0a704147ec8e32 > > dashboard link: https://syzkaller.appspot.com/bug?extid=f0fae482604e6d9a87c9 > > compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2 > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=13a63dbe700000 > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10e150a1700000 > > > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > > Reported-by: syzbot+f0fae482604e6d9a87c9@xxxxxxxxxxxxxxxxxxxxxxxxx > > > #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 0014404f9c18 > > > From 785609ab0d95c753dc31267b3c4da585c16e0274 Mon Sep 17 00:00:00 2001 > From: Oliver Neukum <oneukum@xxxxxxxx> > Date: Thu, 10 Mar 2022 10:40:36 +0100 > Subject: [PATCH] USB: hub: fix memory leak on failure of usb_get_config > > kfree()s on the error path need to be added. No, they don't. The config and rawdescriptors buffers get freed later on in usb_destroy_configuration(). This problem is something else. Probably whatever driver is calling gspca_probe() (see the console log) is taking a reference to the usb_device or usb_interface and then failing to release that reference on its error path. Alan Stern > Signed-off-by: Oliver Neukum <oneukum@xxxxxxxx> > --- > drivers/usb/core/config.c | 17 +++++++++++++---- > 1 file changed, 13 insertions(+), 4 deletions(-) > > diff --git a/drivers/usb/core/config.c b/drivers/usb/core/config.c > index 48bc8a4814ac..548ce5ca6847 100644 > --- a/drivers/usb/core/config.c > +++ b/drivers/usb/core/config.c > @@ -885,12 +885,16 @@ int usb_get_configuration(struct usb_device *dev) > > length = ncfg * sizeof(char *); > dev->rawdescriptors = kzalloc(length, GFP_KERNEL); > - if (!dev->rawdescriptors) > - return -ENOMEM; > + if (!dev->rawdescriptors) { > + result = -ENOMEM; > + goto err2; > + } > > desc = kmalloc(USB_DT_CONFIG_SIZE, GFP_KERNEL); > - if (!desc) > - return -ENOMEM; > + if (!desc) { > + result = -ENOMEM; > + goto err2; > + } > > for (cfgno = 0; cfgno < ncfg; cfgno++) { > /* We grab just the first descriptor so we know how long > @@ -952,6 +956,11 @@ int usb_get_configuration(struct usb_device *dev) > err: > kfree(desc); > dev->descriptor.bNumConfigurations = cfgno; > +err2: > + kfree(dev->rawdescriptors); > + kfree(dev->config); > + dev->rawdescriptors = NULL; > + dev->config = NULL; > > return result; > } > -- > 2.34.1 >
