Fix panic when size 0 passed to malloc #3303

anuraaga · 2022-11-21T03:19:28Z

Currently it will panic (I think Go may translate &buf[0] without a length check)

https://linux.die.net/man/3/realloc

malloc/calloc can return NULL for empty size
realloc with empty is equivalent to free

dgryski

LGTM.

deadprogram · 2022-11-21T20:00:31Z

Thank you for the fixes @anuraaga and thanks for reviewing @dgryski

Also, thanks for the helpful link @anuraaga

Now merging.

PR tinygo-org#3303 addressed panics when malloc'ing with size 0 by returning nil. While this is permitted by the C standard, some wasm environments expect the behavior to match that of glibc/dlmalloc, which is to always return a unique pointer.

The issue with "fragment is larger than or outside of variable" is a known issue and has been resolved in tinygo v0.26. However, tinygo v0.26 introduces a regression for wasm/wasi target where the compiler panics when size 0 passed to malloc. See tinygo-org/tinygo#3303 for details Signed-off-by: Jiaxiao Zhou <[email protected]>

* created wit-bindgen-gen-guest-go crate and added to the clap CLI Signed-off-by: Jiaxiao Zhou <[email protected]> * rewrote import and export using a more generic conversion method Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: records working Signed-off-by: Jiaxiao Zhou <[email protected]> * simply code Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: tuple works Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: list works Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: string works Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: option works Signed-off-by: Jiaxiao Zhou <[email protected]> * implemented result type Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: result works Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: result option work Signed-off-by: Jiaxiao Zhou <[email protected]> * added codegen for go bindgen. Further work needs to pass all the tests Signed-off-by: Jiaxiao Zhou <[email protected]> * get more tests passed, including conventions Signed-off-by: Jiaxiao Zhou <[email protected]> * now flags and alias are working Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: implemented multi-return Signed-off-by: Jiaxiao Zhou <[email protected]> cargo clippy Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: implemented union, enum and variantss Signed-off-by: Jiaxiao Zhou <[email protected]> * rewrite lower's Result for imports * avoid Go keywords conflict with wit's variable names Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: all codegen tests passed. The issue with "fragment is larger than or outside of variable" is a known issue and has been resolved in tinygo v0.26. However, tinygo v0.26 introduces a regression for wasm/wasi target where the compiler panics when size 0 passed to malloc. See tinygo-org/tinygo#3303 for details Signed-off-by: Jiaxiao Zhou <[email protected]> * refactor: add gen-guest-c dependency to gen-guest-go. Signed-off-by: Jiaxiao Zhou <[email protected]> * cargo lock file Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: passed new tests associated cross-interface feature Signed-off-by: Jiaxiao Zhou <[email protected]> * formatted code Signed-off-by: Jiaxiao Zhou <[email protected]> * gh action: installed tinygo Signed-off-by: Jiaxiao Zhou <[email protected]> * install go 1.19 Signed-off-by: Jiaxiao Zhou <[email protected]> * generate C files together with Go files Signed-off-by: Jiaxiao Zhou <[email protected]> * added option-result test Signed-off-by: Jiaxiao Zhou <[email protected]> * fix a typo in wit-bindgen-cli doc Signed-off-by: Jiaxiao Zhou <[email protected]> * updated README to include gen-guest-go Signed-off-by: Jiaxiao Zhou <[email protected]> * removed option-result.wit Signed-off-by: Jiaxiao Zhou <[email protected]> * fix the broken CLI Signed-off-by: Jiaxiao Zhou <[email protected]> * added go to runtime test Signed-off-by: Jiaxiao Zhou <[email protected]> * free C parameters and variables Signed-off-by: Jiaxiao Zhou <[email protected]> * removed memory free for return variables in export and invoke arguments in import Signed-off-by: Jiaxiao Zhou <[email protected]> * implemented lists Signed-off-by: Jiaxiao Zhou <[email protected]> * fixed a small bug around lowering nested option types Signed-off-by: Jiaxiao Zhou <[email protected]> * improve readability of code Signed-off-by: Jiaxiao Zhou <[email protected]> * changed the variant's package name to the world's name. Signed-off-by: Jiaxiao Zhou <[email protected]> * milestone: re-implement results Signed-off-by: Jiaxiao Zhou <[email protected]> * Fixed a small reference issue for lowering result * re-implement variants and unions Signed-off-by: Jiaxiao Zhou <[email protected]> * fixed a few small bugs around variants and union types. Added variant runtime tests Signed-off-by: Jiaxiao Zhou <[email protected]> * turn off gc-leaking in tinygo 0.26 Signed-off-by: Jiaxiao Zhou <[email protected]> * simplify code and add multi-return to lowering * Added runtime tests for list, number and variant * Added flavorful runtime test * Added tests for many_aguments, records and smoke * Added strings and unions runtime tests * removed http from runtime test Signed-off-by: Jiaxiao Zhou <[email protected]> * added go bindgen build step to ci * updated tinygo to 0.27. All tests should pass now Signed-off-by: Jiaxiao Zhou <[email protected]> * fixed go version to 1.20 instead of 1.2 Signed-off-by: Jiaxiao Zhou <[email protected]> * disable string test because unicode hasn't been handled properly Signed-off-by: Jiaxiao Zhou <[email protected]> * deleted wasm abi flag * merged main Signed-off-by: Jiaxiao Zhou <[email protected]> * Move go's files to it's own subfolder * move C gen files to its own folder Signed-off-by: Jiaxiao Zhou <[email protected]> * update go from 1.19 to 1.20 Signed-off-by: Jiaxiao Zhou <[email protected]> * changed tinygo crate version to 0.1.0 Signed-off-by: Jiaxiao Zhou <[email protected]> * diable variants test for go Signed-off-by: Jiaxiao Zhou <[email protected]> * Fixed a missing argument to encode * Fix referring to foreign imported paths in go Signed-off-by: Jiaxiao Zhou <[email protected]> * disable lift-foreign tests for now Signed-off-by: Jiaxiao Zhou <[email protected]> * run rustfmt Signed-off-by: Jiaxiao Zhou <[email protected]> --------- Signed-off-by: Jiaxiao Zhou <[email protected]>

anuraaga mentioned this pull request Nov 21, 2022

wasm error running example knqyf263/go-plugin#7

Closed

Fix panic when size 0 passed to malloc

46701eb

anuraaga force-pushed the malloc-empty-fix branch from e646a0d to 46701eb Compare November 21, 2022 04:25

dgryski approved these changes Nov 21, 2022

View reviewed changes

deadprogram merged commit b731919 into tinygo-org:dev Nov 21, 2022

lann mentioned this pull request Nov 22, 2022

Http-go template fails spinframework/spin#820

Closed

lann mentioned this pull request Jan 24, 2023

Return unique pointer when size 0 passed to malloc #3410

Closed

anuraaga mentioned this pull request Feb 3, 2023

ci: switch to Go 1.20 #3426

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Fix panic when size 0 passed to malloc #3303

Fix panic when size 0 passed to malloc #3303

anuraaga commented Nov 21, 2022

dgryski left a comment

deadprogram commented Nov 21, 2022

Fix panic when size 0 passed to malloc #3303

Fix panic when size 0 passed to malloc #3303

Conversation

anuraaga commented Nov 21, 2022

dgryski left a comment

Choose a reason for hiding this comment

deadprogram commented Nov 21, 2022