From b6cb31e0a068b77218ed393eca4ce67655f23cfe Mon Sep 17 00:00:00 2001 From: Kevin Brodsky Date: Thu, 12 May 2016 09:53:26 +0100 Subject: [PATCH] FROMLIST: [PATCH 2/6] arm64: elf: Set AT_SYSINFO_EHDR in compat processes (cherry pick from url https://patchwork.kernel.org/patch/10060431/) If the compat vDSO is enabled, we need to set AT_SYSINFO_EHDR in the auxiliary vector of compat processes to the address of the vDSO code page, so that the dynamic linker can find it (just like the regular vDSO). Note that we cast context.vdso to Elf64_Off, instead of elf_addr_t, because elf_addr_t is Elf32_Off in compat_binfmt_elf.c, and casting context.vdso to u32 would trigger a pointer narrowing warning. Signed-off-by: Kevin Brodsky Signed-off-by: Mark Salyzyn Cc: Catalin Marinas Cc: Will Deacon Cc: Dave Martin Cc: "Eric W. Biederman" Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Bug: 63737556 Bug: 20045882 Change-Id: I5d0b191d3b2f4c0b2ec31fe9faef0246253635ce --- arch/arm64/include/asm/elf.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h index 40a8a94db23b..d46c1941cfae 100644 --- a/arch/arm64/include/asm/elf.h +++ b/arch/arm64/include/asm/elf.h @@ -140,11 +140,12 @@ typedef struct user_fpsimd_state elf_fpregset_t; #define SET_PERSONALITY(ex) clear_thread_flag(TIF_32BIT); /* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */ -#define ARCH_DLINFO \ +#define _SET_AUX_ENT_VDSO \ do { \ NEW_AUX_ENT(AT_SYSINFO_EHDR, \ - (elf_addr_t)current->mm->context.vdso); \ + (Elf64_Off)current->mm->context.vdso); \ } while (0) +#define ARCH_DLINFO _SET_AUX_ENT_VDSO #define ARCH_HAS_SETUP_ADDITIONAL_PAGES struct linux_binprm; @@ -184,7 +185,11 @@ typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG]; #define compat_start_thread compat_start_thread #define COMPAT_SET_PERSONALITY(ex) set_thread_flag(TIF_32BIT); +#ifdef CONFIG_VDSO32 +#define COMPAT_ARCH_DLINFO _SET_AUX_ENT_VDSO +#else #define COMPAT_ARCH_DLINFO +#endif extern int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp); #define compat_arch_setup_additional_pages \ -- 2.20.1