Anchor all referenced loop variables #4991
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This enables the gosec linter. It also disables a number of warnings which it emits on the current codebase. Some of these (e.g. G104: Errors unhandles) we expect to leave disabled permanently; others (e.g. G601: Implicit memory aliasing in for loop) we expect to fix and then enable to prevent regressions. Fixes #4948
(cherry picked from commit 788c0c1)
(cherry picked from commit 61a54b7)
Taking a reference to a loop variable produced by a range statement can be dangerous. If that pointer is preserved elsewhere, for example by being passed to a function which stores it, the resulting behavior may not be what the author or reader expects. When it is not feasible to structure code such that references to loop variables are not taken at all, the loop variable can instead be 'anchored' by assigning it to itself. This change anchors all loop range variables which are referenced and then passed to arbitrary functions. It also removes our exclusion of gosec'c G601 lint rule, which catches this error, to ensure we don't reintroduce it later. Fixes #4986
jsha
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Jul 28, 2020
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Looks good. Needs a merge and conflict resolve.
jsha
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Jul 28, 2020
rolandshoemaker
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Jul 29, 2020
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Taking a reference to a loop variable produced by a range statement
can be dangerous. If that pointer is preserved elsewhere, for example
by being passed to a function which stores it, the resulting behavior
may not be what the author or reader expects.
When it is not feasible to structure code such that references to
loop variables are not taken at all, the loop variable can instead be
'anchored' by assigning it to itself.
This change anchors all loop range variables which are referenced and
then passed to arbitrary functions. It also removes our exclusion of
gosec'c G601 lint rule, which catches this error, to ensure we don't
reintroduce it later.
Depends on #4990
Fixes #4948