Example: bounds7.c

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prev: bounds6.c
next: bounds8.c

    #include <cheriintrin.h>
    #include <stdio.h>
    
    static char *encode(unsigned char password)
    {
        char *p = NULL;
        return cheri_bounds_set(p, password);
    }
    
    static void decode(char *msg)
    {
        size_t password = cheri_length_get(msg);
        fprintf(stderr,"Your password was %zu\n", password);
    }
    
    int main()
    {
        char *x = encode(42);
        if(x==NULL)
            decode(x);
    }

Experimental data (what does this mean?)

clang-riscv-O3-bounds-conservative
clang-riscv-O3-bounds-subobject-safe
 
exit codes: compile 0 / execute 1

Program received signal SIGPROT, CHERI protection violation.
Capability tag fault caused by register cnull.
main () at tests/cheri/bounds7.c:18
18     char *x = encode(42);
#0  main () at tests/cheri/bounds7.c:18
        x = <optimized out>


 
clang-riscv-O0-bounds-conservative
clang-riscv-O0-bounds-references-only
clang-riscv-O0-bounds-subobject-safe
clang-riscv-O0-bounds-aggressive
clang-riscv-O0-bounds-very-aggressive
clang-riscv-O0-bounds-everywhere-unsafe
 
exit codes: compile 0 / execute 1

Program received signal SIGPROT, CHERI protection violation.
Capability tag fault caused by register ca0.
0x000000000010189a in encode (password=42 '*') at tests/cheri/bounds7.c:7
7      return cheri_bounds_set(p, password);
#0  0x000000000010189a in encode (password=42 '*') at tests/cheri/bounds7.c:7
        p = 0x0
#1  0x0000000000101838 in main () at tests/cheri/bounds7.c:18
        x = 0x4011316a <rtld_nop_exit> [rxR,0x40103000-0x4012b300] (sentry,capmode) "\202\200]q\206\240\"\270&\260J\250N\240\027W\001"


 
clang-morello-O3-bounds-conservative
clang-morello-O3-bounds-subobject-safe
 
Your password was 18446744073709551615
 
gcc-morello-O0
gcc-morello-O3
clang-morello-O0-bounds-conservative
clang-morello-O0-bounds-references-only
clang-morello-O0-bounds-subobject-safe
clang-morello-O0-bounds-aggressive
clang-morello-O0-bounds-very-aggressive
clang-morello-O0-bounds-everywhere-unsafe
cerberus-cheri
cerberus-cheri-no-pnvi
cerberus-cheri-revocation
cerberus-cheri-revocation-no-pnvi
cerberus-cheri-cornucopia
cerberus-cheri-cornucopia-no-pnvi
 
Your password was 42