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    SubjectRe: [patch] remove MNT_NOEXEC check for PROT_EXEC mmaps
    Hi.

    Valdis.Kletnieks@vt.edu wrote:
    >> But why exactly? They do:
    >> shm_open();
    >> mmap(PROT_READ|PROT_WRITE|PROT_EXEC);
    >> and mmap fails.
    >> Where is the fault of an app here?
    > Are you suggesting that it's not an app's fault/problem if it tries to
    > open a writable file on a R/O filesystem? Because it's essentially the
    > same problem....
    It is not really the same - the app is not trying to
    create an "executable" file on a noexec filesystem.
    PROT_EXEC never required the exec permission on a file
    btw. The MAP_PRIVATE mmap roughly means a read of the
    file into the memory, where the program can do anything
    with its data, including an execution. Does the R/O
    filesystem disallow PROT_WRITE for MAP_PRIVATE? Haven't
    tried, but I hope it doesn't.

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