CVE-2026-74631 — net: smc: fix splice entry lifetime imbalance in smc_rx_splice
In the Linux kernel, the following vulnerability has been resolved: net: smc: fix splice entry lifetime imbalance in smc_rx_splice smc_rx_splice() passes pages to splice_to_pi…
Published: 2026-08-22 · CVSS: 8.4 · CVSS 3.1
In the Linux kernel, the following vulnerability has been resolved: net: smc: fix splice entry lifetime imbalance in smc_rx_splice smc_rx_splice() passes pages to splice_to_pipe() before taking the references that cover the lifetime of each splice entry. In the VM-backed RMB path, splice_to_pipe() may drop unqueued entries through smc_rx_spd_release(), while queued entries are released later via the pipe buffer callback. The old post-splice accounting also derives the number of queued VM pages from an offset mutated while building the descriptor, and a multi-page splice pairs one sock_hold() with multiple sock_put() calls. Take the page and socket references for every candidate entry before splice_to_pipe(), and drop the matching private state, page reference, and socket reference from smc_rx_spd_release() for entries that never get queued. This fixes a refcount imbalance that can underflow page refcounts and trigger a use-after-free.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7