diff options
| -rw-r--r-- | fs/binfmt_elf_fdpic.c | 50 |
1 files changed, 43 insertions, 7 deletions
diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c index 80c1f952ef78..e4eb472558ca 100644 --- a/fs/binfmt_elf_fdpic.c +++ b/fs/binfmt_elf_fdpic.c @@ -455,6 +455,16 @@ error_kill: } /*****************************************************************************/ + +#ifndef ELF_BASE_PLATFORM +/* + * AT_BASE_PLATFORM indicates the "real" hardware/microarchitecture. + * If the arch defines ELF_BASE_PLATFORM (in asm/elf.h), the value + * will be copied to the user stack in the same manner as AT_PLATFORM. + */ +#define ELF_BASE_PLATFORM NULL +#endif + /* * present useful information to the program */ @@ -466,8 +476,8 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, unsigned long sp, csp, nitems; elf_caddr_t __user *argv, *envp; size_t platform_len = 0, len; - char *k_platform; - char __user *u_platform, *p; + char *k_platform, *k_base_platform; + char __user *u_platform, *u_base_platform, *p; long hwcap; int loop; int nr; /* reset for each csp adjustment */ @@ -483,11 +493,14 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, return -EFAULT; #endif - /* get hold of platform and hardware capabilities masks for the machine - * we are running on. In some cases (Sparc), this info is impossible - * to get, in others (i386) it is merely difficult. - */ hwcap = ELF_HWCAP; + + /* + * If this architecture has a platform capability string, copy it + * to userspace. In some cases (Sparc), this info is impossible + * for userspace to get any other way, in others (i386) it is + * merely difficult. + */ k_platform = ELF_PLATFORM; u_platform = NULL; @@ -499,6 +512,21 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, return -EFAULT; } + /* + * If this architecture has a "base" platform capability + * string, copy it to userspace. + */ + k_base_platform = ELF_BASE_PLATFORM; + u_base_platform = NULL; + + if (k_base_platform) { + platform_len = strlen(k_base_platform) + 1; + sp -= platform_len; + u_base_platform = (char __user *) sp; + if (__copy_to_user(u_base_platform, k_base_platform, platform_len) != 0) + return -EFAULT; + } + #if defined(__i386__) && defined(CONFIG_SMP) /* in some cases (e.g. Hyper-Threading), we want to avoid L1 evictions * by the processes running on the same package. One thing we can do is @@ -543,7 +571,8 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, /* force 16 byte _final_ alignment here for generality */ #define DLINFO_ITEMS 13 - nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH; + nitems = 1 + DLINFO_ITEMS + (k_platform ? 1 : 0) + + (k_base_platform ? 1 : 0) + AT_VECTOR_SIZE_ARCH; csp = sp; sp -= nitems * 2 * sizeof(unsigned long); @@ -575,6 +604,13 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm, (elf_addr_t) (unsigned long) u_platform); } + if (k_base_platform) { + nr = 0; + csp -= 2 * sizeof(unsigned long); + NEW_AUX_ENT(AT_BASE_PLATFORM, + (elf_addr_t) (unsigned long) u_base_platform); + } + nr = 0; csp -= DLINFO_ITEMS * 2 * sizeof(unsigned long); NEW_AUX_ENT(AT_HWCAP, hwcap); |