Fix overflow handling for private key loading #34558

1. 
   gzJx0DuTRHytnHe7P5RmMbPf3wKy2BztweVGXTf commented at 1:04 pm on February 11, 2026: none

   This pull request makes a small but important change to the handling of invalid private keys in the secp256k1_ellswift_xdh function. The update ensures that the overflow flag properly reflects both cases: when the scalar is invalid due to overflow and when it is zero.

   • Improved private key validation logic: The overflow check now combines both overflow and zero checks using a bitwise OR, ensuring that invalid keys are consistently replaced with a safe default. (src/secp256k1/src/modules/ellswift/main_impl.h, src/secp256k1/src/modules/ellswift/main_impl.hL567-R567)
2. Fix overflow handling for private key loading b3f70a5ead
3. 
   DrahtBot commented at 1:05 pm on February 11, 2026: contributor

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4. 
   fanquake commented at 1:38 pm on February 11, 2026: member

   Changes to subtrees should be opened against that repo. i.e https://github.com/bitcoin-core/secp256k1
5. fanquake closed this on Feb 11, 2026

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Contributors
gzJx0DuTRHytnHe7P5RmMbPf3wKy2BztweVGXTf DrahtBot fanquake