The bio_map_user_iov and bio_unmap_user functions in block/bio.c in the Linux kernel before 4.13.8 do unbalanced refcounting when a SCSI I/O vector has small consecutive buffers belonging to the same page. The bio_add_pc_page function merges them into one, but the page reference is never dropped. This causes a memory leak and possible system lockup (exploitable against the host OS by a guest OS user, if a SCSI disk is passed through to a virtual machine) due to an out-of-memory condition.
5.13.0-19.193.11.0-12.193.12.0-1.33.12.0-2.53.12.0-2.73.12.0-3.83.12.0-3.93.12.0-4.103.12.0-4.123.12.0-5.133.12.0-7.15+116 more3.13.0-142.1914.13.0-16.194.13.0-17.206.5.0-9.94.2.0-16.194.2.0-17.214.2.0-19.234.3.0-1.104.3.0-2.114.3.0-5.164.3.0-6.174.3.0-7.184.4.0-10.254.4.0-101.124+59 more4.4.0-116.1406.8.0-31.315.3.0-18.195.3.0-24.265.4.0-9.125.13.0-1005.64.4.0-1002.24.4.0-1003.34.4.0-1005.54.4.0-1006.64.4.0-1009.94.4.0-1010.104.4.0-1011.114.4.0-1012.124.4.0-1014.144.15.0-1001.1Exploitability
AV:LAC:LPR:LUI:NScope
S:CImpact
C:NI:NA:HCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H