CVE-2026-68289tipc: fix integer overflow in tipc_recvmsg() and tipc_recvstream()

Official description

In the Linux kernel, the following vulnerability has been resolved: tipc: fix integer overflow in tipc_recvmsg() and tipc_recvstream() In tipc_recvmsg(), the copy length is computed as: copy = min_t(int, dlen - offset, buflen); buflen is size_t but min_t(int, ...) casts it to int. When buflen exceeds INT_MAX (e.g. 0xFFFFFFFF via io_uring provided buffers), it wraps negative, wins the comparison, and the negative copy length propagates to simple_copy_to_iter() where int-to-size_t promotion makes it SIZE_MAX, triggering a WARN_ON. tipc_recvstream() has the same pattern. Kernel panic - not syncing: kernel: panic_on_warn set ... RIP: 0010:simple_copy_to_iter+0x9e/0xd0 (net/core/datagram.c:521) Call Trace: __skb_datagram_iter+0x123/0x8b0 (net/core/datagram.c:402) skb_copy_datagram_iter+0x77/0x1a0 (net/core/datagram.c:534) tipc_recvmsg+0x3d7/0xe80 (net/tipc/socket.c:1934) io_recvmsg+0x47e/0xda0 Fix by changing min_t(int, ...) to min_t(size_t, ...) in both functions. The result is always <= (dlen - offset), which is bounded by TIPC maximum message size (0x1ffff bytes), so the implicit narrowing on assignment to int copy is always safe.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/9fd4f92671146b068809b6c34b50346cb30cf8f7
• https://git.kernel.org/stable/c/93580911f02d1f4a506ec0a6fc4354140c53ffe8
• https://git.kernel.org/stable/c/1b6066313b9b8fac870483bf7a26d6bd56579747
• https://git.kernel.org/stable/c/7364014fdc289225229eb08de8bcbf4580e78e4d
• https://git.kernel.org/stable/c/fe9bf32bb18f2d35789d4960fb007d1059bbaa38
• https://git.kernel.org/stable/c/47f42ff521b4eeb46e82f9a46a4783a99f7570d7