[Bug 264473] uverbs: Fix a race with disassociate and exit_mmap()
Date: Sun, 05 Jun 2022 12:38:09 UTC
https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=264473 Bug ID: 264473 Summary: uverbs: Fix a race with disassociate and exit_mmap() Product: Base System Version: Unspecified Hardware: Any OS: Any Status: New Severity: Affects Only Me Priority: --- Component: kern Assignee: bugs@FreeBSD.org Reporter: firstname.lastname@example.org Created attachment 234462 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=234462&action=edit a possible patch If uverbs_user_mmap_disassociate() is called while the mmap is concurrently doing exit_mmap then the ordering of the rdma_user_mmap_entry_put() is not reliable. The put must be done before uvers_user_mmap_disassociate() returns, otherwise there can be a use after free on the ucontext, and a left over entry in the xarray. If the put is not done here then it is done during rdma_umap_close() later. Add the missing put to the error exit path. -- You are receiving this mail because: You are the assignee for the bug.