On 10/3/20 7:38 PM, Philippe Mathieu-Daudé wrote:
> On 10/2/20 11:59 PM, Richard Henderson wrote:
>> For BTI, we need to know if the executable is static or dynamic,
>> which means looking for PT_INTERP earlier.
>>
>> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
>> ---
>> linux-user/elfload.c | 60 +++++++++++++++++++++++---------------------
>> 1 file changed, 31 insertions(+), 29 deletions(-)
>>
>> diff --git a/linux-user/elfload.c b/linux-user/elfload.c
>> index 735ebfa190..6b422990ff 100644
>> --- a/linux-user/elfload.c
>> +++ b/linux-user/elfload.c
>> @@ -2421,8 +2421,10 @@ static void load_elf_image(const char *image_name,
>> int image_fd,
>>
>> mmap_lock();
>>
>> - /* Find the maximum size of the image and allocate an appropriate
>> - amount of memory to handle that. */
>> + /*
>> + * Find the maximum size of the image and allocate an appropriate
>> + * amount of memory to handle that. Locate the interpreter, if any.
>> + */
>> loaddr = -1, hiaddr = 0;
>> info->alignment = 0;
>> for (i = 0; i < ehdr->e_phnum; ++i) {
>> @@ -2438,6 +2440,33 @@ static void load_elf_image(const char *image_name,
>> int image_fd,
>> }
>> ++info->nsegs;
>> info->alignment |= eppnt->p_align;
>> + } else if (eppnt->p_type == PT_INTERP && pinterp_name) {
>> + char *interp_name;
>> +
>> + if (*pinterp_name) {
>> + errmsg = "Multiple PT_INTERP entries";
>> + goto exit_errmsg;
>> + }
>> + interp_name = malloc(eppnt->p_filesz);
>> + if (!interp_name) {
>> + goto exit_perror;
>> + }
>> +
>> + if (eppnt->p_offset + eppnt->p_filesz <= BPRM_BUF_SIZE) {
>> + memcpy(interp_name, bprm_buf + eppnt->p_offset,
>> + eppnt->p_filesz);
>> + } else {
>> + retval = pread(image_fd, interp_name, eppnt->p_filesz,
>> + eppnt->p_offset);
>> + if (retval != eppnt->p_filesz) {
>
> Preexisting, free(interp_name)?
I just sent a patch using g_steal_pointer() instead:
https://lists.gnu.org/archive/html/qemu-devel/2020-10/msg00792.html
(Maybe I should have tagged it RFC as this is the first
time I try this API).
>
>> + goto exit_perror;
>> + }
>> + }
>> + if (interp_name[eppnt->p_filesz - 1] != 0) {
>> + errmsg = "Invalid PT_INTERP entry";
>
> Ditto, otherwise:
> Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org>
>
>> + goto exit_errmsg;
>> + }
>> + *pinterp_name = interp_name;
>> }
>> }
>>
>> @@ -2590,33 +2619,6 @@ static void load_elf_image(const char *image_name,
>> int image_fd,
>> if (vaddr_em > info->brk) {
>> info->brk = vaddr_em;
>> }
>> - } else if (eppnt->p_type == PT_INTERP && pinterp_name) {
>> - char *interp_name;
>> -
>> - if (*pinterp_name) {
>> - errmsg = "Multiple PT_INTERP entries";
>> - goto exit_errmsg;
>> - }
>> - interp_name = malloc(eppnt->p_filesz);
>> - if (!interp_name) {
>> - goto exit_perror;
>> - }
>> -
>> - if (eppnt->p_offset + eppnt->p_filesz <= BPRM_BUF_SIZE) {
>> - memcpy(interp_name, bprm_buf + eppnt->p_offset,
>> - eppnt->p_filesz);
>> - } else {
>> - retval = pread(image_fd, interp_name, eppnt->p_filesz,
>> - eppnt->p_offset);
>> - if (retval != eppnt->p_filesz) {
>> - goto exit_perror;
>> - }
>> - }
>> - if (interp_name[eppnt->p_filesz - 1] != 0) {
>> - errmsg = "Invalid PT_INTERP entry";
>> - goto exit_errmsg;
>> - }
>> - *pinterp_name = interp_name;
>> #ifdef TARGET_MIPS
>> } else if (eppnt->p_type == PT_MIPS_ABIFLAGS) {
>> Mips_elf_abiflags_v0 abiflags;
>>
>
>
