internal/poll: move rsan to heap on windows#159
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nickkhyl merged 1 commit intotailscale.go1.26from Mar 9, 2026
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According to https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-wsarecvfrom, the memory pointed to by lpFromlen must remain available during the overlapped I/O, and therefore cannot be allocated on the stack. CL 685417 moved the rsan field out of the operation struct and placed it on stack, which violates the above requirement and causes stack corruption. Unfortunately, it is no longer possible to cleanly revert CL 685417. Instead of attempting to revert it, this CL bundles rsan together with rsa in the same sync.Pool. The new wsaRsa struct is still in the same size class, so no additional overhead is introduced by this change. Updates golang#77975 Updates tailscale/tailscale#18884 Updates #158 Cherry-picked from https://go-review.googlesource.com/c/go/+/753040 v4 Reviewed-on: https://go-review.googlesource.com/c/go/+/753040 Reviewed-by: Quim Muntal <quimmuntal@gmail.com> Reviewed-by: Damien Neil <dneil@google.com> Change-Id: I5ffbccb332515116ddc03fb7c40ffc9293cad2ab
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According to https://learn.microsoft.com/en-us/windows/win32/api/winsock2/nf-winsock2-wsarecvfrom, the memory pointed to by lpFromlen must remain available during the overlapped I/O, and therefore cannot be allocated on the stack.
CL 685417 moved the rsan field out of the operation struct and placed it on stack, which violates the above requirement and causes stack corruption.
Unfortunately, it is no longer possible to cleanly revert CL 685417. Instead of attempting to revert it, this CL bundles rsan together with rsa in the same sync.Pool. The new wsaRsa struct is still in the same size class, so no additional overhead is introduced by this change.
Updates golang#77975
Updates tailscale/tailscale#18884
Updates #158
Cherry-picked from https://go-review.googlesource.com/c/go/+/753040 v4
Reviewed-on: https://go-review.googlesource.com/c/go/+/753040
Reviewed-by: Quim Muntal quimmuntal@gmail.com
Reviewed-by: Damien Neil dneil@google.com
Change-Id: I5ffbccb332515116ddc03fb7c40ffc9293cad2ab