CyberRota Analysis
AI-GeneratedThe vulnerability affects the Linux kernel's handling of socket connections, specifically in the `smc_rx_pipe_buf_release()` function, which can lead to a use-after-free condition due to improper synchronization between socket state checks and resource deallocation. This flaw could potentially allow an attacker to exploit the race condition, leading to memory corruption or arbitrary code execution. Organizations using Linux systems, particularly those relying on socket communication, should prioritize patching this vulnerability to mitigate the associated risks.
Original NVD Description
In the Linux kernel, the following vulnerability has been resolved: net/smc: fix use-after-free in smc_rx_pipe_buf_release() smc_rx_splice() hands RMB pages to a pipe and takes a socket reference per entry so the smc_sock stays alive until the reader finishes. The connection does not: a concurrent close runs smc_conn_free(), which releases the receive buffer back to the link group pool. smc_rx_pipe_buf_release() tests sk_state before taking the socket lock. The state can change between the test and the lock, and smc_rx_update_cons() then dereferences conn->rmb_desc and walks conn->lgr, which smc_conn_free() has already released. On the is_reg_err path smcr_buf_unuse() frees the descriptor outright, so this is a use-after-free. Take the socket lock first and test conn->freed instead. smc_conn_free() sets that flag before releasing anything, and every caller holds the socket lock. The two paths exclude each other: either the pipe release runs first with everything valid, or it sees the flag and skips the update.