On 23 April 2018 at 08:51, Christophe Lyon <christophe.l...@st.com> wrote:
> Add FDPIC info into image_info structure since interpreter info is on
> stack and needs to be saved to be accessed later on.
>
> Co-Authored-By: Mickaël Guêné <mickael.gu...@st.com>
> Signed-off-by: Christophe Lyon <christophe.l...@st.com>
>
> diff --git a/linux-user/elfload.c b/linux-user/elfload.c
> index 76d7718..1ee1e38 100644
> --- a/linux-user/elfload.c
> +++ b/linux-user/elfload.c
> @@ -78,6 +78,11 @@ enum {
> */
> #define personality(pers) (pers & PER_MASK)
>
> +int info_is_fdpic(struct image_info *info)
> +{
> + return (info->personality == PER_LINUX_FDPIC);
> +}
> +
> /* this flag is uneffective under linux too, should be deleted */
> #ifndef MAP_DENYWRITE
> #define MAP_DENYWRITE 0
> @@ -287,6 +292,24 @@ static inline void init_thread(struct target_pt_regs
> *regs,
> /* For uClinux PIC binaries. */
> /* XXX: Linux does this only on ARM with no MMU (do we care ?) */
> regs->uregs[10] = infop->start_data;
> +
> + /* Support ARM FDPIC. */
> + if (info_is_fdpic(infop)) {
> + /* As described in the ABI document, r7 points to the loadmap
> info
> + * prepared by the kernel. If an interpreter is needed, r8 points
> + * to the interpreter loadmap and r9 points to the interpreter
> + * PT_DYNAMIC info. If no interpreter is needed, r8 is zer0, and
"zero"
> + * r9 points to the main program PT_DYNAMIC info. */
Something odd seems to have happened to the indentation here.
Nit: */ should be on a line of its own.
> + regs->uregs[7] = infop->loadmap_addr;
> + if (infop->interpreter_loadmap_addr) {
> + /* Executable is dynamically loaded. */
> + regs->uregs[8] = infop->interpreter_loadmap_addr;
> + regs->uregs[9] = infop->interpreter_pt_dynamic_addr;
> + } else {
> + regs->uregs[8] = 0;
> + regs->uregs[9] = infop->pt_dynamic_addr;
> + }
> + }
> }
>
> #define ELF_NREG 18
> @@ -1745,6 +1768,11 @@ static abi_ulong create_elf_tables(abi_ulong p, int
> argc, int envc,
> if (interp_info) {
> interp_info->other_info = info;
> sp = loader_build_fdpic_loadmap(interp_info, sp);
> + info->interpreter_loadmap_addr = interp_info->loadmap_addr;
> + info->interpreter_pt_dynamic_addr = interp_info->pt_dynamic_addr;
> + } else {
> + info->interpreter_loadmap_addr = 0;
> + info->interpreter_pt_dynamic_addr = 0;
> }
> }
>
> diff --git a/linux-user/main.c b/linux-user/main.c
> index 2acac36..3579f0e 100644
> --- a/linux-user/main.c
> +++ b/linux-user/main.c
> @@ -4893,6 +4893,9 @@ int main(int argc, char **argv, char **envp)
> env->cp15.sctlr_el[1] |= SCTLR_B;
> }
> #endif
> +
> + /* Are we running an FDPIC binary? */
> + ((TaskState *)thread_cpu->opaque)->is_fdpic = info_is_fdpic(info);
> }
> #elif defined(TARGET_SPARC)
> {
> diff --git a/linux-user/qemu.h b/linux-user/qemu.h
> index da3b517..a2ed148 100644
> --- a/linux-user/qemu.h
> +++ b/linux-user/qemu.h
> @@ -57,6 +57,8 @@ struct image_info {
> uint16_t nsegs;
> void *loadsegs;
> abi_ulong pt_dynamic_addr;
> + abi_ulong interpreter_loadmap_addr;
> + abi_ulong interpreter_pt_dynamic_addr;
> struct image_info *other_info;
> };
>
> @@ -145,6 +147,9 @@ typedef struct TaskState {
> */
> int signal_pending;
>
> + /* We need to know if we have an FDPIC binary to adapt signal
> + * syscalls. */
> + int is_fdpic;
Looking at the TaskState struct it already has a pointer
to the image_info struct. So we could just have something like
bool task_is_fdpic(TaskState *ts)
{
return ts->info->personality == PER_LINUX_FDPIC;
}
and save the need to set up and test a separate flag, I think.
Otherwise looks good.
thanks
-- PMM
