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Use `throw_unsup_format` instead of returning `ENOTSUP` in the mmap shim · rust-lang/rust@37a37f6

2 files changed

lines changed

Original file line numberDiff line numberDiff line change

@@ -71,24 +71,27 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {

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throw_unsup_format!("Miri does not support file-backed memory mappings");

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}

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// POSIX says:

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// [ENOTSUP]

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// * MAP_FIXED or MAP_PRIVATE was specified in the flags argument and the implementation

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// does not support this functionality.

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// * The implementation does not support the combination of accesses requested in the

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// prot argument.

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//

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// Miri doesn't support MAP_FIXED or any any protections other than PROT_READ|PROT_WRITE.

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if flags & map_fixed != 0 || prot != prot_read | prot_write {

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this.set_last_error(this.eval_libc("ENOTSUP"))?;

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return Ok(this.eval_libc("MAP_FAILED"));

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// Miri doesn't support MAP_FIXED.

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if flags & map_fixed != 0 {

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throw_unsup_format!(

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"Miri does not support calls to mmap with MAP_FIXED as part of the flags argument",

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);

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}

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// Miri doesn't support protections other than PROT_READ|PROT_WRITE.

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if prot != prot_read | prot_write {

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throw_unsup_format!(

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"Miri does not support calls to mmap with protections other than \

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PROT_READ|PROT_WRITE",

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);

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}

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// Miri does not support shared mappings, or any of the other extensions that for example

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// Linux has added to the flags arguments.

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if flags != map_private | map_anonymous {

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throw_unsup_format!(

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"Miri only supports calls to mmap which set the flags argument to MAP_PRIVATE|MAP_ANONYMOUS"

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"Miri only supports calls to mmap which set the flags argument to \

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MAP_PRIVATE|MAP_ANONYMOUS",

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);

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}

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Original file line numberDiff line numberDiff line change

@@ -69,36 +69,6 @@ fn test_mmap<Offset: Default>(

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assert_eq!(ptr, libc::MAP_FAILED);

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assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::EINVAL);

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let ptr = unsafe {

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mmap(

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ptr::without_provenance_mut(page_size * 64),

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page_size,

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libc::PROT_READ | libc::PROT_WRITE,

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// We don't support MAP_FIXED

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libc::MAP_PRIVATE | libc::MAP_ANONYMOUS | libc::MAP_FIXED,

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-1,

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Default::default(),

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)

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};

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assert_eq!(ptr, libc::MAP_FAILED);

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assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::ENOTSUP);

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// We don't support protections other than read+write

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for prot in [libc::PROT_NONE, libc::PROT_EXEC, libc::PROT_READ, libc::PROT_WRITE] {

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let ptr = unsafe {

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mmap(

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ptr::null_mut(),

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page_size,

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prot,

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libc::MAP_PRIVATE | libc::MAP_ANONYMOUS,

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-1,

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Default::default(),

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)

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};

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assert_eq!(ptr, libc::MAP_FAILED);

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assert_eq!(Error::last_os_error().raw_os_error().unwrap(), libc::ENOTSUP);

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}

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// We report an error for mappings whose length cannot be rounded up to a multiple of

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// the page size.

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let ptr = unsafe {