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charset=us-ascii Content-Disposition: inline In-Reply-To: <6a49b585-05d0-4b79-b5ab-d710f5d6d598@app.fastmail.com> X-Stat-Signature: igjnp8hs3884681hp8easw6i4ooxxurk X-Rspamd-Server: rspam10 X-Rspamd-Queue-Id: 58BC5C0009 X-Rspam-User: X-HE-Tag: 1689965576-699853 X-HE-Meta: U2FsdGVkX18AAB5B2YJZ39vl5+abxMtKcwgABSBzE3YNKLftNwxLMSSPWvGcv6odsdGs6Vz8XvRw4rlpYSB5YTbYEipIgbcEvqOGp1zpwNavpAtq11T0wYs/ZSt1idUNFE3lcrQ1Lt7ZeFjFqGrlQafquud89Q5mq+QcIbZ+NwtLTEyhjG4OwjYBGGTEntk0Je+Mb9ioDkaiF91Hbvpd5wf9kKE2xlwPQQGEC4jnbxBTVVSOFZvXaQCEWk1Vosl2PtrqTI5lZy4aW3sb7pQGurn+FAqpzUVDRWIIS7mGU+DhVp3h6Q26pcU4afpF44LGfzMFkMeinPsIjVTsCQJJPTglhN9vah2cHsiclmJ6iV5/cxcZiMMzlML3RyugHOiP5DPcdLjMcUMSFTqEpQ/JnSJCsSFG1Xb4cOJG9W3LQdhWh6OlIrlMtcIxbTvmxkl9adnh73P+5/WoI73igY4DjI+wFKupOVBeEgtpIhtdTXXGCkcDCeUawhzpRMEx/GKJZO3ayVsfDFaiSIIWCtvDdY+159wyqSzMk9rCSpC9UmFioMp8XqBp9TJ0f379f0kGo8DqyzVgN5gDuJf3w2CN8QU06Sfj6s9pambVvpK3CIjIstb3IT5Qnljl+Xzv3Tgq9NtXbP+wfto9wT5HYNQwVoraGMu+NlkUGstss1JGpMW6MhPD3QZgNMrq6ghPCJiXS8CjIncbb87f757fFZyNLlAlXUBCeszAdQ4p0BPsBGEpF6jnroXJsunhn25/K9Dmrjp3UWc3yfhOHPjjgynOUHs08/sRfyRQ4dYNzkLKKu9W4viQmJKqUA61U8yrvsMG+vIgHG3lvEUZ+BnyKzpHBBNEPQuiSV9Rcg8uitdL/241RIFjewFSyvMio84d30Oz00gVpeqrfGGx25xbot2Rxwwy73Ib4TFj+LHnB5dFGd7xAoF9VtrB8YrEMnyaIfteSjnhWJAxyZmrA0wrtGL WkumcAvD 9ujfG+9otYBJrCPRGeWB4hQzEuI7GFLxu5PMjTtQVkMznqlY/VXN4z82Z5IQCOUnTa2DnrNsscKL6pcvk6aPch5AL0mFcrO5YfcAJj30rs1gaMMIFg2OxPvLpnd6nW5zG7WDztkkseyIKtYk5hPcNY+OEZg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Jul 21, 2023 at 05:47:31PM +0200, Arnd Bergmann wrote: > On Fri, Jul 21, 2023, at 12:22, Peter Zijlstra wrote: > > * futex_parse_waitv - Parse a waitv array from userspace > > @@ -207,7 +207,12 @@ static int futex_parse_waitv(struct fute > > if ((aux.flags & ~FUTEX2_MASK) || aux.__reserved) > > return -EINVAL; > > > > - if (!(aux.flags & FUTEX2_32)) > > + if (!IS_ENABLED(CONFIG_64BIT) || in_compat_syscall()) { > > + if ((aux.flags & FUTEX2_64) == FUTEX2_64) > > + return -EINVAL; > > + } > > + > > + if ((aux.flags & FUTEX2_64) != FUTEX2_32) > > return -EINVAL; > > This looks slightly confusing, how about defining another > FUTEX2_SIZEMASK (or similar) macro to clarify that > "aux.flags & FUTEX2_64" is a mask operation that can > match the FUTEX2_{8,16,32,64} values? Yeah, I had that in an earlier version, but then reconsidered as I didn't want to clutter the uabi with that. But perhaps I over-throught this.