Stream: git-wasmtime

Topic: wasmtime / PR #7443 Fix Winch bug for funcs with params a...

Wasmtime GitHub notifications bot (Nov 01 2023 at 15:53):

jeffcharles opened PR #7443 from jeffcharles:winch-defined-locals-range-fix to bytecodealliance:main:

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I noticed a differential fuzzing failure in Winch when running the following module:

(module
  (type (;0;) (func (param i64)))
  (func (;0;) (type 0) (param i64)
    (local i32)
    global.get 1
    i32.eqz
    if ;; label = @1
      unreachable
    end
    global.get 1
    i32.const 1
    i32.sub
    global.set 1
    local.get 1
    local.tee 1
    global.get 0
    i32.xor
    global.set 0
  )
  (global (;0;) (mut i32) i32.const 0)
  (global (;1;) (mut i32) i32.const 1000)
  (export "\00\01\00" (func 0))
  (export "" (global 0))
)

I was able to narrow a repro case down to:

(module
  (func (;0;) (param i32) (result i32)
    (local i32)
    local.get 1
  )
  (export "t" (func 0))
)

This strongly hinted that there was a potential issue with locals when there is a param present.

In the area of code I have changed, defined_locals.stack_size may be an equal or lower value than defined_locals_start since defined_locals_start is set based on the number and type of parameters and defined_locals.stack_size is set based on the number and type of locals but not parameters. The range should be defined_locals_start to defined_locals_start plus defined_locals.stack_size.

Wasmtime GitHub notifications bot (Nov 01 2023 at 15:53):

jeffcharles requested abrown for a review on PR #7443.

Wasmtime GitHub notifications bot (Nov 01 2023 at 15:53):

jeffcharles requested wasmtime-compiler-reviewers for a review on PR #7443.

Wasmtime GitHub notifications bot (Nov 01 2023 at 16:21):

saulecabrera submitted PR review:

Thanks!

Wasmtime GitHub notifications bot (Nov 01 2023 at 16:21):

saulecabrera has enabled auto merge for PR #7443.

Wasmtime GitHub notifications bot (Nov 01 2023 at 17:05):

saulecabrera merged PR #7443.

Last updated: Dec 23 2024 at 13:07 UTC