[tor-bugs] #24037 [Core Tor/Torsocks]: Use syscall blacklist rather than whitelist for torsocks

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#24037: Use syscall blacklist rather than whitelist for torsocks
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 Reporter:  cypherpunks        |          Owner:  dgoulet
     Type:  enhancement        |         Status:  needs_review
 Priority:  Medium             |      Milestone:
Component:  Core Tor/Torsocks  |        Version:
 Severity:  Normal             |     Resolution:
 Keywords:                     |  Actual Points:
Parent ID:                     |         Points:
 Reviewer:                     |        Sponsor:
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Comment (by cypherpunks):

 A few comments about the patch:

 >`unsigned long a0, a1, a2, a3, a4, a5;`

 While this type is certainly correct for 64-bit Linux on x86 systems, it
 might be better to use something like `ptrdiff_t`, and maybe even use a
 macro to choose the number of arguments dynamically (since `ptrdiff_t
 a[NUM]` would work perfectly as well), since Linux's isn't the only
 syscall ABI out there. I can't help but have the nagging feeling that
 there may be a way to avoid hardcoding the number of arguments at all, and
 instead use a single `va_arg` for everything.

 >`tsocks_libc_syscall(number, a0, a1, a2, a3, a4, a5);`

 This should probably be using a `return`, otherwise the `ret` could be
 used uninitialized.

 >`ret = tsocks_socket(a0, a1, a2);`
 >`break;`

 You could also replacing this (and others like it) with just a `return
 tsocks_socket(a0, a1, a2);`, to get rid of that temporary `ret` entirely
 and make the code a bit more clean.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/24037#comment:4>
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