shim_seccomp: stop allowing sched_yield#3023
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sporksmith merged 2 commits intoshadow:mainfrom Jun 13, 2023
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We needed this exception before to avoid recursive syscall interception in our spinlock implementation. Now that we're allowing direct syscalls from the shim's whole `.text` segment, we don't need to allow `sched_yield` by syscall number. Fixes shadow#2681: Removing this exception allows us to intercept direct `sched_yield` syscalls that *aren't* made from the shim itself, thereby letting us escape spin loops that use them. Progress on shadow#2790: asan has such spin loops in its thread-creatio wrappers.
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stevenengler
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Jun 13, 2023
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Oh, I should've just used Rustix's |
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actually maybe it's just as well to use |
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We needed this exception before to avoid recursive syscall interception in our spinlock implementation. Now that we're allowing direct syscalls from the shim's whole
.textsegment, we don't need to allowsched_yieldby syscall number.Fixes #2681: Removing this exception allows us to intercept direct
sched_yieldsyscalls that aren't made from the shim itself, thereby letting us escape spin loops that use them.Progress on #2790: asan has such spin loops in its thread-creation wrappers.