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Bug fix in libelfloader
+18
-4
+18
-4
src/libelfloader/loader.c
+18
-4
src/libelfloader/loader.c
···
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uintptr_t off = phdr->p_offset - ELF_PAGEOFFSET(phdr->p_vaddr);
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addr = ELF_PAGESTART(addr);
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-
size = ELF_PAGEALIGN(size);
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+
// size = ELF_PAGEALIGN(size);
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if (phdr->p_flags & PF_X)
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prot |= PROT_EXEC;
···
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if (phdr->p_flags & PF_R)
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prot |= PROT_READ;
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-
if (phdr->p_flags & PF_W)
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+
//if (phdr->p_flags & PF_W)
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flags |= MAP_PRIVATE;
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-
else
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-
flags |= MAP_SHARED;
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//else
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// flags |= MAP_SHARED;
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bool needszeroing = size != ELF_PAGEALIGN(size);
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if (needszeroing)
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prot |= PROT_WRITE;
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if (mprotect((void*) (addr), memsize, prot) == -1)
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{
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perror("mprotect");
···
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{
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perror("mmap");
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goto out;
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+
}
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+
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// Based on experiments, when we provide a size that is less than a multiple of page size
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// mmap() will map up to the whole page of file data anyway. Many ELF files, including ld.so,
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// however rely on the rest of the page being zeroed out.
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if (needszeroing)
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{
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memset((void*)(addr + size), 0, ELF_PAGEALIGN(size) - size);
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if (!(phdr->p_flags & PF_W))
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mprotect((void*) (addr), memsize, prot & ~PROT_WRITE);
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}
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/*