CVE-2018-12232
In net/socket.c in the Linux kernel through 4.17.1, there is a race condition between fchownat and close in cases where they target the same socket file descriptor, related to the sock_close and sockfs_setattr functions. fchownat does not increment the file descriptor reference count, which allows close to set the socket to NULL during fchownat's execution, leading to a NULL pointer dereference and system crash.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In net/socket.c in the Linux kernel through 4.17.1, there is a race condition between fchownat and close in cases where they target the same socket file descriptor, related to the sock_close and sockfs_setattr functions. fchownat does not increment the file descriptor reference count, which allows close to set the socket to NULL during fchownat's execution, leading to a NULL pointer dereference and system crash.
05 / REFERENCES
Further evidence
- http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6d8c50dcb029872b298eea68cc6209c866fd3e14
- http://www.securityfocus.com/bid/104453
- https://access.redhat.com/errata/RHSA-2018:2948
- https://github.com/torvalds/linux/commit/6d8c50dcb029872b298eea68cc6209c866fd3e14
- https://lkml.org/lkml/2018/6/5/14
- https://patchwork.ozlabs.org/patch/926519/
- https://usn.ubuntu.com/3752-1/
- https://usn.ubuntu.com/3752-2/
- https://usn.ubuntu.com/3752-3/