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47f42ff521
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. Fixes:e9f8b10101("tipc: refactor function tipc_sk_recvmsg()") Fixes:ec8a09fbbe("tipc: refactor function tipc_sk_recv_stream()") Reported-by: AutonomousCodeSecurity@microsoft.com Signed-off-by: Cen Zhang (Microsoft) <blbllhy@gmail.com> Reviewed-by: Tung Nguyen <tung.quang.nguyen@est.tech> Link: https://patch.msgid.link/20260720214103.47732-1-blbllhy@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>