[tor-bugs] #24099 [Core Tor/Tor]: tor should remove empty/invalid consensus cache files (Unable to map file from consensus cache: Numerical result out of range)

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#24099: tor should remove empty/invalid consensus cache files (Unable to map file
from consensus cache: Numerical result out of range)
--------------------------+------------------------------------
 Reporter:  Hello71       |          Owner:  nickm
     Type:  defect        |         Status:  needs_review
 Priority:  Low           |      Milestone:  Tor: 0.3.2.x-final
Component:  Core Tor/Tor  |        Version:
 Severity:  Minor         |     Resolution:
 Keywords:  031-backport  |  Actual Points:
Parent ID:                |         Points:
 Reviewer:                |        Sponsor:
--------------------------+------------------------------------

Comment (by dgoulet):

 I'm a bit confused here, `ERANGE` is not documented as an errno value from
 `mmap(2)` both on Linux and FreeBSD. It seems that the range issue is
 handled with:

 {{{
   EINVAL We don't like addr, length, or offset (e.g., they are too large,
 or not aligned on a page boundary).
 }}}

 @Hello71, what is your kernel version here? I've checked (on kernel 4.14)
 and XFS doesn't seem to be returning `ERANGE` in the case of a mmap...

 The fix lgtm; but this `ERANGE` thing is just weird and confusing to me
 from which syscall this can come. The `open()`, `fstat()` and `mmap()`
 don't seem to never return that :S ...

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/24099#comment:4>
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