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[WRAPPER] Check the validity of the path before my_execve #4371

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[WRAPPER] Check the validity of the path before my_execve #4371

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17 changes: 17 additions & 0 deletions src/wrapped/wrappedlibc.c
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Original file line number Diff line number Diff line change
Expand Up @@ -2160,6 +2160,20 @@ static long isProcMem(const char* path)
return 0;
}

static int isPathValid(const char* path)
{
if(!path)
return 0;
uintptr_t p = (uintptr_t)path;
for(size_t i = 0; i < 4096; ++i) {

@ptitSeb ptitSeb Sep 9, 2026

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the 4096 magic constant should be a MACRO constant instead

if(!(getProtection_fast(p + i) & PROT_READ))

@ptitSeb ptitSeb Sep 9, 2026

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Do not call getprotection if page didn't change, use a local cache.

return 0;
if(!path[i])
return 1;
}
return 0;
}

// buf may not end with NULL and prefix must end with NULL.
static int start_with(char *buf, ssize_t buflen, char *prefix)
{
Expand Down Expand Up @@ -2923,6 +2937,9 @@ EXPORT int32_t my_execv(x64emu_t* emu, const char* path, char* const argv[])

EXPORT int32_t my_execve(x64emu_t* emu, const char* path, char* const argv[], char* const envp[])
{
if(!isPathValid(path))
return execve(path, argv, envp);

int self = isProcSelf(path, "exe");
int x64 = FileIsX64ELF(path);
int x86 = my_context->box86path?FileIsX86ELF(path):0;
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