CVE-2024-56769

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> media: dvb-frontends: dib3000mb: fix uninit-value in dib3000_write_reg<br /> <br /> Syzbot reports [1] an uninitialized value issue found by KMSAN in<br /> dib3000_read_reg().<br /> <br /> Local u8 rb[2] is used in i2c_transfer() as a read buffer; in case<br /> that call fails, the buffer may end up with some undefined values.<br /> <br /> Since no elaborate error handling is expected in dib3000_write_reg(),<br /> simply zero out rb buffer to mitigate the problem.<br /> <br /> [1] Syzkaller report<br /> dvb-usb: bulk message failed: -22 (6/0)<br /> =====================================================<br /> BUG: KMSAN: uninit-value in dib3000mb_attach+0x2d8/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758<br /> dib3000mb_attach+0x2d8/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758<br /> dibusb_dib3000mb_frontend_attach+0x155/0x2f0 drivers/media/usb/dvb-usb/dibusb-mb.c:31<br /> dvb_usb_adapter_frontend_init+0xed/0x9a0 drivers/media/usb/dvb-usb/dvb-usb-dvb.c:290<br /> dvb_usb_adapter_init drivers/media/usb/dvb-usb/dvb-usb-init.c:90 [inline]<br /> dvb_usb_init drivers/media/usb/dvb-usb/dvb-usb-init.c:186 [inline]<br /> dvb_usb_device_init+0x25a8/0x3760 drivers/media/usb/dvb-usb/dvb-usb-init.c:310<br /> dibusb_probe+0x46/0x250 drivers/media/usb/dvb-usb/dibusb-mb.c:110<br /> ...<br /> Local variable rb created at:<br /> dib3000_read_reg+0x86/0x4e0 drivers/media/dvb-frontends/dib3000mb.c:54<br /> dib3000mb_attach+0x123/0x3c0 drivers/media/dvb-frontends/dib3000mb.c:758<br /> ...