[PATCH 07/19] elf: Use sysinfo_ehdr in ARCH_DLINFO()

Dmitry Safonov
2020-11-08T05:17:17Z

Instead mm->context.vdso use the pointer provided by elf loader.
That allows to drop the pointer on arm/s390/sparc.

Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
---
arch/alpha/include/asm/elf.h | 2 +-
arch/arm/include/asm/elf.h | 5 ++---
arch/arm64/include/asm/elf.h | 18 +++++-------------
arch/ia64/include/asm/elf.h | 2 +-
arch/mips/include/asm/elf.h | 5 ++---
arch/nds32/include/asm/elf.h | 5 ++---
arch/powerpc/include/asm/elf.h | 4 ++--
arch/riscv/include/asm/elf.h | 5 ++---
arch/s390/include/asm/elf.h | 5 ++---
arch/sh/include/asm/elf.h | 10 +++++-----
arch/sparc/include/asm/elf_64.h | 5 ++---
arch/x86/include/asm/elf.h | 33 ++++++++++++++-------------------
arch/x86/um/asm/elf.h | 4 ++--
fs/binfmt_elf.c | 6 +++---
fs/binfmt_elf_fdpic.c | 11 ++++++-----
15 files changed, 51 insertions(+), 69 deletions(-)

diff --git a/arch/alpha/include/asm/elf.h b/arch/alpha/include/asm/elf.h
index 8049997fa372..701e820f28f0 100644
--- a/arch/alpha/include/asm/elf.h
+++ b/arch/alpha/include/asm/elf.h
@@ -155,7 +155,7 @@ extern int alpha_l2_cacheshape;
extern int alpha_l3_cacheshape;

/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
NEW_AUX_ENT(AT_L1I_CACHESHAPE, alpha_l1i_cacheshape); \
NEW_AUX_ENT(AT_L1D_CACHESHAPE, alpha_l1d_cacheshape); \
diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h
index 1f4b91a17a91..7bb07056242f 100644
--- a/arch/arm/include/asm/elf.h
+++ b/arch/arm/include/asm/elf.h
@@ -133,10 +133,9 @@ extern void elf_set_personality(const struct elf32_hdr *);
#define SET_PERSONALITY(ex) elf_set_personality(&(ex))

#ifdef CONFIG_VDSO
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (elf_addr_t)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} while (0)
#endif

diff --git a/arch/arm64/include/asm/elf.h b/arch/arm64/include/asm/elf.h
index a81953bcc1cf..e62818967a69 100644
--- a/arch/arm64/include/asm/elf.h
+++ b/arch/arm64/include/asm/elf.h
@@ -165,10 +165,9 @@ typedef struct user_fpsimd_state elf_fpregset_t;
})

/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (elf_addr_t)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
\
/* \
* Should always be nonzero unless there's a kernel bug. \
@@ -223,19 +222,12 @@ typedef compat_elf_greg_t compat_elf_gregset_t[COMPAT_ELF_NGREG];
set_thread_flag(TIF_32BIT); \
})
#ifdef CONFIG_COMPAT_VDSO
-#define COMPAT_ARCH_DLINFO \
+#define COMPAT_ARCH_DLINFO(sysinfo_ehdr) \
do { \
- /* \
- * Note that we use Elf64_Off instead of elf_addr_t because \
- * elf_addr_t in compat is defined as Elf32_Addr and casting \
- * current->mm->context.vdso to it triggers a cast warning of \
- * cast from pointer to integer of different size. \
- */ \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (Elf64_Off)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} while (0)
#else
-#define COMPAT_ARCH_DLINFO
+#define COMPAT_ARCH_DLINFO(sysinfo_ehdr)
#endif

#endif /* CONFIG_COMPAT */
diff --git a/arch/ia64/include/asm/elf.h b/arch/ia64/include/asm/elf.h
index 6629301a2620..a257e5abddce 100644
--- a/arch/ia64/include/asm/elf.h
+++ b/arch/ia64/include/asm/elf.h
@@ -208,7 +208,7 @@ struct task_struct;
#define GATE_EHDR ((const struct elfhdr *) GATE_ADDR)

/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
extern char __kernel_syscall_via_epc[]; \
NEW_AUX_ENT(AT_SYSINFO, (unsigned long) __kernel_syscall_via_epc); \
diff --git a/arch/mips/include/asm/elf.h b/arch/mips/include/asm/elf.h
index 6665cf7870b3..5bdc8d00ac37 100644
--- a/arch/mips/include/asm/elf.h
+++ b/arch/mips/include/asm/elf.h
@@ -474,10 +474,9 @@ extern const char *__elf_base_platform;
#endif

/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (unsigned long)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} while (0)

#ifdef CONFIG_MIPS_FP_SUPPORT
diff --git a/arch/nds32/include/asm/elf.h b/arch/nds32/include/asm/elf.h
index 36cec4ae5a84..4f5894208efe 100644
--- a/arch/nds32/include/asm/elf.h
+++ b/arch/nds32/include/asm/elf.h
@@ -165,13 +165,12 @@ struct elf32_hdr;
#define FPU_AUX_ENT NEW_AUX_ENT(AT_IGNORE, 0)
#endif

-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
/* Optional FPU initialization */ \
FPU_AUX_ENT; \
\
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (elf_addr_t)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} while (0)

#endif
diff --git a/arch/powerpc/include/asm/elf.h b/arch/powerpc/include/asm/elf.h
index ba0e1e331088..b1ae4411f4bd 100644
--- a/arch/powerpc/include/asm/elf.h
+++ b/arch/powerpc/include/asm/elf.h
@@ -155,7 +155,7 @@ extern int ucache_bsize;
* even if DLINFO_ARCH_ITEMS goes to zero or is undefined.
* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes
*/
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
/* Handle glibc compatibility. */ \
NEW_AUX_ENT(AT_IGNOREPPC, AT_IGNOREPPC); \
@@ -164,7 +164,7 @@ do { \
NEW_AUX_ENT(AT_DCACHEBSIZE, dcache_bsize); \
NEW_AUX_ENT(AT_ICACHEBSIZE, icache_bsize); \
NEW_AUX_ENT(AT_UCACHEBSIZE, ucache_bsize); \
- VDSO_AUX_ENT(AT_SYSINFO_EHDR, current->mm->context.vdso_base); \
+ VDSO_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
ARCH_DLINFO_CACHE_GEOMETRY; \
} while (0)

diff --git a/arch/riscv/include/asm/elf.h b/arch/riscv/include/asm/elf.h
index 628444d3bbab..3c270c7c32f3 100644
--- a/arch/riscv/include/asm/elf.h
+++ b/arch/riscv/include/asm/elf.h
@@ -58,10 +58,9 @@ extern unsigned long elf_hwcap;
#define ELF_PLATFORM (NULL)

#ifdef CONFIG_MMU
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (elf_addr_t)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
NEW_AUX_ENT(AT_L1I_CACHESIZE, \
get_cache_size(1, CACHE_TYPE_INST)); \
NEW_AUX_ENT(AT_L1I_CACHEGEOMETRY, \
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h
index f6ce9df8a996..1087a52f3257 100644
--- a/arch/s390/include/asm/elf.h
+++ b/arch/s390/include/asm/elf.h
@@ -269,11 +269,10 @@ do { \
#define STACK_RND_MASK MMAP_RND_MASK

/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
if (vdso_enabled) \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (unsigned long)current->mm->context.vdso_base); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} while (0)

#endif
diff --git a/arch/sh/include/asm/elf.h b/arch/sh/include/asm/elf.h
index 9b3e22e771a1..03b813c0bc39 100644
--- a/arch/sh/include/asm/elf.h
+++ b/arch/sh/include/asm/elf.h
@@ -170,13 +170,13 @@ extern void __kernel_vsyscall;
#define VDSO_BASE ((unsigned long)current->mm->context.vdso)
#define VDSO_SYM(x) (VDSO_BASE + (unsigned long)(x))

-#define VSYSCALL_AUX_ENT \
+#define VSYSCALL_AUX_ENT(sysinfo_ehdr) \
if (vdso_enabled) \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_BASE); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
else \
NEW_AUX_ENT(AT_IGNORE, 0)
#else
-#define VSYSCALL_AUX_ENT NEW_AUX_ENT(AT_IGNORE, 0)
+#define VSYSCALL_AUX_ENT(sysinfo_ehdr) NEW_AUX_ENT(AT_IGNORE, 0)
#endif /* CONFIG_VSYSCALL */

#ifdef CONFIG_SH_FPU
@@ -188,13 +188,13 @@ extern void __kernel_vsyscall;
extern int l1i_cache_shape, l1d_cache_shape, l2_cache_shape;

/* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT entries changes */
-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
/* Optional FPU initialization */ \
FPU_AUX_ENT; \
\
/* Optional vsyscall entry */ \
- VSYSCALL_AUX_ENT; \
+ VSYSCALL_AUX_ENT(sysinfo_ehdr); \
\
/* Cache desc */ \
NEW_AUX_ENT(AT_L1I_CACHESHAPE, l1i_cache_shape); \
diff --git a/arch/sparc/include/asm/elf_64.h b/arch/sparc/include/asm/elf_64.h
index 63a622c36df3..1e7295b5ae2f 100644
--- a/arch/sparc/include/asm/elf_64.h
+++ b/arch/sparc/include/asm/elf_64.h
@@ -213,12 +213,11 @@ do { if ((ex).e_ident[EI_CLASS] == ELFCLASS32) \

extern unsigned int vdso_enabled;

-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
extern struct adi_config adi_state; \
if (vdso_enabled) \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (unsigned long)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
NEW_AUX_ENT(AT_ADI_BLKSZ, adi_state.caps.blksz); \
NEW_AUX_ENT(AT_ADI_NBITS, adi_state.caps.nbits); \
NEW_AUX_ENT(AT_ADI_UEONADI, adi_state.caps.ue_on_adi); \
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index 51a08f6b18e5..ace9e9da3521 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -306,11 +306,14 @@ extern u32 elf_hwcap2;

struct task_struct;

-#define ARCH_DLINFO_IA32 \
+#define VDSO_ENTRY(sysinfo_ehdr) \
+ (sysinfo_ehdr + vdso_image_32.sym___kernel_vsyscall)
+
+#define ARCH_DLINFO_IA32(sysinfo_ehdr) \
do { \
- if (VDSO_CURRENT_BASE) { \
- NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY); \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, VDSO_CURRENT_BASE); \
+ if (sysinfo_ehdr) { \
+ NEW_AUX_ENT(AT_SYSINFO, VDSO_ENTRY(sysinfo_ehdr)); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} \
} while (0)

@@ -344,39 +347,31 @@ extern bool mmap_address_hint_valid(unsigned long addr, unsigned long len);
#define __STACK_RND_MASK(is32bit) ((is32bit) ? 0x7ff : 0x3fffff)
#define STACK_RND_MASK __STACK_RND_MASK(mmap_is_ia32())

-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
if (vdso64_enabled) \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (unsigned long __force)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} while (0)

/* As a historical oddity, the x32 and x86_64 vDSOs are controlled together. */
-#define ARCH_DLINFO_X32 \
+#define ARCH_DLINFO_X32(sysinfo_ehdr) \
do { \
if (vdso64_enabled) \
- NEW_AUX_ENT(AT_SYSINFO_EHDR, \
- (unsigned long __force)current->mm->context.vdso); \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, sysinfo_ehdr); \
} while (0)

#define AT_SYSINFO 32

-#define COMPAT_ARCH_DLINFO \
+#define COMPAT_ARCH_DLINFO(sysinfo_ehdr) \
if (exec->e_machine == EM_X86_64) \
- ARCH_DLINFO_X32; \
+ ARCH_DLINFO_X32(sysinfo_ehdr); \
else \
- ARCH_DLINFO_IA32
+ ARCH_DLINFO_IA32(sysinfo_ehdr)

#define COMPAT_ELF_ET_DYN_BASE (TASK_UNMAPPED_BASE + 0x1000000)

#endif /* !CONFIG_X86_32 */

-#define VDSO_CURRENT_BASE ((unsigned long)current->mm->context.vdso)
-
-#define VDSO_ENTRY \
- ((unsigned long)current->mm->context.vdso + \
- vdso_image_32.sym___kernel_vsyscall)
-
/* Do not change the values. See get_align_mask() */
enum align_flags {
ALIGN_VA_32 = BIT(0),
diff --git a/arch/x86/um/asm/elf.h b/arch/x86/um/asm/elf.h
index 7bc1d9d94d66..953c6b7f992e 100644
--- a/arch/x86/um/asm/elf.h
+++ b/arch/x86/um/asm/elf.h
@@ -88,7 +88,7 @@ extern unsigned long __kernel_vsyscall;
#define AT_SYSINFO 32
#define AT_SYSINFO_EHDR 33

-#define ARCH_DLINFO \
+#define ARCH_DLINFO(sysinfo_ehdr) \
do { \
if ( vsyscall_ehdr ) { \
NEW_AUX_ENT(AT_SYSINFO, __kernel_vsyscall); \
@@ -183,7 +183,7 @@ do { \

extern unsigned long um_vdso_addr;
#define AT_SYSINFO_EHDR 33
-#define ARCH_DLINFO NEW_AUX_ENT(AT_SYSINFO_EHDR, um_vdso_addr)
+#define ARCH_DLINFO(sysinfo_ehdr) NEW_AUX_ENT(AT_SYSINFO_EHDR, um_vdso_addr)

#endif

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 049ff514aa19..bc81f29b3cfb 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -171,7 +171,7 @@ static int padzero(unsigned long elf_bss)
static int
create_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec,
unsigned long load_addr, unsigned long interp_load_addr,
- unsigned long e_entry)
+ unsigned long e_entry, unsigned long sysinfo_ehdr)
{
struct mm_struct *mm = current->mm;
unsigned long p = bprm->p;
@@ -251,7 +251,7 @@ create_elf_tables(struct linux_binprm *bprm, const struct elfhdr *exec,
* update AT_VECTOR_SIZE_ARCH if the number of NEW_AUX_ENT() in
* ARCH_DLINFO changes
*/
- ARCH_DLINFO;
+ ARCH_DLINFO(sysinfo_ehdr);
#endif
NEW_AUX_ENT(AT_HWCAP, ELF_HWCAP);
NEW_AUX_ENT(AT_PAGESZ, ELF_EXEC_PAGESIZE);
@@ -1255,7 +1255,7 @@ static int load_elf_binary(struct linux_binprm *bprm)
goto out;

retval = create_elf_tables(bprm, elf_ex,
- load_addr, interp_load_addr, e_entry);
+ load_addr, interp_load_addr, e_entry, sysinfo_ehdr);
if (retval < 0)
goto out;

diff --git a/fs/binfmt_elf_fdpic.c b/fs/binfmt_elf_fdpic.c
index c9ee3c240855..f0e4803ab6ca 100644
--- a/fs/binfmt_elf_fdpic.c
+++ b/fs/binfmt_elf_fdpic.c
@@ -63,7 +63,7 @@ static int elf_fdpic_map_file(struct elf_fdpic_params *, struct file *,

static int create_elf_fdpic_tables(struct linux_binprm *, struct mm_struct *,
struct elf_fdpic_params *,
- struct elf_fdpic_params *);
+ struct elf_fdpic_params *, unsigned long);

#ifndef CONFIG_MMU
static int elf_fdpic_map_file_constdisp_on_uclinux(struct elf_fdpic_params *,
@@ -434,8 +434,8 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
current->mm->start_stack = current->mm->start_brk + stack_size;
#endif

- if (create_elf_fdpic_tables(bprm, current->mm,
- &exec_params, &interp_params) < 0)
+ if (create_elf_fdpic_tables(bprm, current->mm, &exec_params,
+ &interp_params, sysinfo_ehdr) < 0)
goto error;

kdebug("- start_code %lx", current->mm->start_code);
@@ -496,7 +496,8 @@ static int load_elf_fdpic_binary(struct linux_binprm *bprm)
static int create_elf_fdpic_tables(struct linux_binprm *bprm,
struct mm_struct *mm,
struct elf_fdpic_params *exec_params,
- struct elf_fdpic_params *interp_params)
+ struct elf_fdpic_params *interp_params,
+ unsigned long sysinfo_ehdr)
{
const struct cred *cred = current_cred();
unsigned long sp, csp, nitems;
@@ -664,7 +665,7 @@ static int create_elf_fdpic_tables(struct linux_binprm *bprm,
/* ARCH_DLINFO must come last so platform specific code can enforce
* special alignment requirements on the AUXV if necessary (eg. PPC).
*/
- ARCH_DLINFO;
+ ARCH_DLINFO(sysinfo_ehdr);
#endif
#undef NEW_AUX_ENT

--
2.28.0