Description
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.
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
n/a Linux kernel through v4.14-rc5
Linux kernel through v4.14-rc5affected
References
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=2b04e8f6bbb196cab4b232af0f8d48ff2c7a8058 ↗
- http://www.securityfocus.com/bid/101911 ↗
- https://lists.debian.org/debian-lts-announce/2017/12/msg00004.html ↗
- https://usn.ubuntu.com/3583-2/ ↗
- https://access.redhat.com/errata/RHSA-2018:1854 ↗
- https://usn.ubuntu.com/3582-1/ ↗
- http://www.kernel.org/pub/linux/kernel/v4.x/ChangeLog-4.13.8 ↗
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=95d78c28b5a85bacbc29b8dba7c04babb9b0d467 ↗
- https://access.redhat.com/errata/RHSA-2018:1062 ↗
- https://github.com/torvalds/linux/commit/95d78c28b5a85bacbc29b8dba7c04babb9b0d467 ↗
- https://access.redhat.com/errata/RHSA-2018:0654 ↗
- https://usn.ubuntu.com/3583-1/ ↗
- https://bugzilla.redhat.com/show_bug.cgi?id=1495089 ↗
- https://github.com/torvalds/linux/commit/2b04e8f6bbb196cab4b232af0f8d48ff2c7a8058 ↗
- http://seclists.org/oss-sec/2017/q4/52 ↗
- https://access.redhat.com/errata/RHSA-2018:0676 ↗
- https://usn.ubuntu.com/3582-2/ ↗
- https://access.redhat.com/errata/RHSA-2019:1170 ↗
- https://access.redhat.com/errata/RHSA-2019:1190 ↗
- https://support.f5.com/csp/article/K93472064?utm_source=f5support&%3Butm_medium=RSS ↗