Re: how does ld.so call ELF's entry?
Sofiane Akermoun <[email protected]> Sun, 7 Apr 2013 06:45:58 +0200
| Newsgroups | org.kernel.vger.linux-assembly |
|---|---|
| Message-ID | <CAN0_x-J_7VOhzezQhWBZNAPfbREtoOkk3yMcS3kLzL5XFD5cwg@mail.gmail.com> |
EntryPoint is set in the ELF Header at assembling/linking time. 2013/4/7 ishare <[email protected]>: > On Sat, Apr 06, 2013 at 08:43:16PM -0700, Chris Evans wrote: >> With a far jump to entry offset > > How does it know the entry point's address? > >> >> >> Sent from my iPad >> >> On Apr 6, 2013, at 8:39 PM, ishare <[email protected]> wrote: >> >> > On Sun, Apr 07, 2013 at 05:11:28AM +0200, Sofiane Akermoun wrote: >> >> Hello, >> >> >> >> >> >> The interpreter is specified during linking process and the program header >> >> of your binary is filled with good values. >> >> Then when the operating system load your binary, he finds next the >> >> interpreter to use. >> >> The linker ld sets the good values by default but you can overwrite it or >> >> specify other values if you want. >> >> The steps are: >> >> 1)The operating system loads your binary >> >> 2)The program loader system execute the Interpreter specifiy in the binary >> >> 3)The interpreter gather all the dynamic libraries needed in memory >> > >> > >> >> 4)The Control is passed to the entry point of your program >> > >> > How does the step 4 been done ? >> > >> > thanks! >> >> >> >> The entry point is specified in your code source as a "global". And could >> >> be find in your object file by the linker. >> >> In theory there are some default tag to specify entry point, like "..start" >> >> for nasm, but you can also passed it to the linker. >> >> >> >> regards, >> >> >> >> Sofiane Akermoun >> >> [email protected] >> >> >> >> >> >> >> >> >> >> >> >> 2013/4/7 ishare <[email protected]> >> >> >> >>> >> >>> For an ELF ,which needs a interpreter , how is it been called by the >> >>> interpreter ? >> >>> >> >>> As I know the interpreter is loaded first and do something essential >> >>> ,then call the main routine of ELF . >> >>> How is this procedure implemented ? >> >>> >> >>> Thanks! >> >>> -- >> >>> To unsubscribe from this list: send the line "unsubscribe linux-assembly" >> >>> in >> >>> the body of a message to [email protected] >> >>> More majordomo info at http://vger.kernel.org/majordomo-info.html >> >> >> >> >> >> >> >> -- >> >> Sofiane AKERMOUN >> >> [email protected] >> > -- >> > To unsubscribe from this list: send the line "unsubscribe linux-assembly" in >> > the body of a message to [email protected] >> > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- > To unsubscribe from this list: send the line "unsubscribe linux-assembly" in > the body of a message to [email protected] > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Sofiane AKERMOUN [email protected]