I'm currently reversing a Linux 32-bit executable (with a statically linked library included in it) but I'm having a little problem I can't find a solution for.

Basically whenever I stumble across a glibc call (memset, memcpy, etc.) IDA, instead of showing the correct name of the function, it shows a reference to MEMORY as a function call.


MEMORY[0xACFC3F9F](s, 0, 44);    // <----- memset
MEMORY[0xACFC3FBD](dest, 0, 40); // <---- memset

The interesting part is that when debugging the reference changes to an actual function call (still unknown, but whatever). While debugging the MEMORY part changes to:

((void (__cdecl *)(char *, _DWORD, signed int))unk_F769B4F0)(s, 0, 44);
((void (__cdecl *)(char *, _DWORD, signed int))unk_F769B4F0)(dest, 0, 40);

In Ghidra the same code looks like this:

memset(s,0,0x2c);    // <--- correct function name
memset(dest,0,0x28); // <--- correct function name

IDA should automatically detect std library functions, what could be the reason why it isn't happening here?

Update: I re-analyzed the executable from scratch (creating a new IDA database) and the references to the functions are here.

Unfortunately, after attaching to the debugger all the function calls became "MEMORY" again.

Here's the asm:

.text:566146D7                 mov     [esp], eax      ; s
.text:566146DA                 call    near ptr memset+566146DBh ; <--- memset call
.text:566146DF                 mov     dword ptr [esp+8], 28h ; '(' ; n
.text:566146E7                 mov     dword ptr [esp+4], 0 ; c
.text:566146EF                 lea     eax, [ebp+dest]
.text:566146F5                 mov     [esp], eax      ; s
.text:566146F8                 call    near ptr memset+566146F9h ; <--- memset call
.text:566146FD                 movsx   eax, [ebp+var_14C]

The memset calls are here but with a memory offset pointing to the next address of the executable.


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