cross-arch: don't corrupt personality flags upon exec()

Historically, the top three bytes of personality have been used for
things such as ADDR_NO_RANDOMIZE, which made sense only for specific
architectures.

We now however have a flag there that is general no matter the
architecture (UNAME26); generally we have to be careful to preserve the
personality flags across exec().

This patch tries to fix all architectures that forcefully overwrite
personality flags during exec() (ppc32 and s390 have been fixed recently
by commits f9783ec862ea ("[S390] Do not clobber personality flags on
exec") and 59e4c3a2fe9c ("powerpc/32: Don't clobber personality flags on
exec") in a similar way already).

Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Cc: Haavard Skinnemoen <hskinnemoen@gmail.com>
Cc: Hans-Christian Egtvedt <egtvedt@samfundet.no>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Mark Salter <msalter@redhat.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Koichi Yasutake <yasutake.koichi@jp.panasonic.com>
Cc: Jonas Bonn <jonas@southpole.se>
Cc: Chen Liqin <liqin.chen@sunplusct.com>
Cc: Lennox Wu <lennox.wu@gmail.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chris Zankel <chris@zankel.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

16 files changed, 31 insertions, 16 deletions

diff --git a/arch/avr32/include/asm/elf.h b/arch/avr32/include/asm/elf.h
index 3b3159b..e2c3287 100644
--- a/arch/avr32/include/asm/elf.h
+++ b/arch/avr32/include/asm/elf.h
@@ -102,6 +102,7 @@ typedef struct user_fpu_struct elf_fpregset_t;
 
 #define ELF_PLATFORM  (NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX_32BIT)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX_32BIT | (current->personality & (~PER_MASK)))
 
 #endif /* __ASM_AVR32_ELF_H */
diff --git a/arch/blackfin/include/asm/elf.h b/arch/blackfin/include/asm/elf.h
index e6c6812..14bc98f 100644
--- a/arch/blackfin/include/asm/elf.h
+++ b/arch/blackfin/include/asm/elf.h
@@ -132,6 +132,7 @@ do {											\
 
 #define ELF_PLATFORM  (NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #endif
diff --git a/arch/c6x/include/asm/elf.h b/arch/c6x/include/asm/elf.h
index f4552db..32b9971 100644
--- a/arch/c6x/include/asm/elf.h
+++ b/arch/c6x/include/asm/elf.h
@@ -77,7 +77,8 @@ do {								\
 
 #define ELF_PLATFORM  (NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 /* C6X specific section types */
 #define SHT_C6000_UNWIND	0x70000001
diff --git a/arch/cris/include/asm/elf.h b/arch/cris/include/asm/elf.h
index 8a3d8e2..8182f2d 100644
--- a/arch/cris/include/asm/elf.h
+++ b/arch/cris/include/asm/elf.h
@@ -86,6 +86,7 @@ typedef unsigned long elf_fpregset_t;
 
 #define ELF_PLATFORM  (NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #endif
diff --git a/arch/frv/include/asm/elf.h b/arch/frv/include/asm/elf.h
index c381980..9ccbc80 100644
--- a/arch/frv/include/asm/elf.h
+++ b/arch/frv/include/asm/elf.h
@@ -137,6 +137,7 @@ do {											\
 
 #define ELF_PLATFORM  (NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #endif
diff --git a/arch/h8300/include/asm/elf.h b/arch/h8300/include/asm/elf.h
index c24fa25..41193c3 100644
--- a/arch/h8300/include/asm/elf.h
+++ b/arch/h8300/include/asm/elf.h
@@ -54,7 +54,8 @@ typedef unsigned long elf_fpregset_t;
 
 #define ELF_PLATFORM  (NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #define R_H8_NONE       0
 #define R_H8_DIR32      1
diff --git a/arch/hexagon/include/asm/elf.h b/arch/hexagon/include/asm/elf.h
index 37976a0..82b4996 100644
--- a/arch/hexagon/include/asm/elf.h
+++ b/arch/hexagon/include/asm/elf.h
@@ -217,7 +217,8 @@ do {					\
 #define ELF_PLATFORM  (NULL)
 
 #ifdef __KERNEL__
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 #endif
 
 #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
diff --git a/arch/m32r/include/asm/elf.h b/arch/m32r/include/asm/elf.h
index b8da7d0..7089616 100644
--- a/arch/m32r/include/asm/elf.h
+++ b/arch/m32r/include/asm/elf.h
@@ -128,6 +128,7 @@ typedef elf_fpreg_t elf_fpregset_t;
    intent than poking at uname or /proc/cpuinfo.  */
 #define ELF_PLATFORM	(NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #endif  /* _ASM_M32R__ELF_H */
diff --git a/arch/m68k/include/asm/elf.h b/arch/m68k/include/asm/elf.h
index e9b7cda5..f83c1d0 100644
--- a/arch/m68k/include/asm/elf.h
+++ b/arch/m68k/include/asm/elf.h
@@ -113,6 +113,7 @@ typedef struct user_m68kfp_struct elf_fpregset_t;
 
 #define ELF_PLATFORM  (NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #endif
diff --git a/arch/microblaze/include/asm/elf.h b/arch/microblaze/include/asm/elf.h
index 834849f..640ddd4 100644
--- a/arch/microblaze/include/asm/elf.h
+++ b/arch/microblaze/include/asm/elf.h
@@ -116,7 +116,8 @@ do {							\
 } while (0)
 
 #ifdef __KERNEL__
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX_32BIT)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX_32BIT | (current->personality & (~PER_MASK)))
 #endif
 
 #endif /* __uClinux__ */
diff --git a/arch/mn10300/include/asm/elf.h b/arch/mn10300/include/asm/elf.h
index 8157c92..4ebd6b3 100644
--- a/arch/mn10300/include/asm/elf.h
+++ b/arch/mn10300/include/asm/elf.h
@@ -151,7 +151,8 @@ do {						\
 #define ELF_PLATFORM  (NULL)
 
 #ifdef __KERNEL__
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 #endif
 
 #endif /* _ASM_ELF_H */
diff --git a/arch/openrisc/include/asm/elf.h b/arch/openrisc/include/asm/elf.h
index a8fe2c5..225a7ff 100644
--- a/arch/openrisc/include/asm/elf.h
+++ b/arch/openrisc/include/asm/elf.h
@@ -110,7 +110,8 @@ extern void dump_elf_thread(elf_greg_t *dest, struct pt_regs *pt);
 
 #define ELF_PLATFORM	(NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #endif /* __KERNEL__ */
 #endif
diff --git a/arch/score/include/asm/elf.h b/arch/score/include/asm/elf.h
index f478ce9..5d566c7 100644
--- a/arch/score/include/asm/elf.h
+++ b/arch/score/include/asm/elf.h
@@ -54,7 +54,7 @@ typedef elf_fpreg_t	elf_fpregset_t;
 
 #define SET_PERSONALITY(ex)					\
 do {								\
-	set_personality(PER_LINUX);				\
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK))); \
 } while (0)
 
 struct task_struct;
diff --git a/arch/sh/include/asm/elf.h b/arch/sh/include/asm/elf.h
index f38112b..37924af 100644
--- a/arch/sh/include/asm/elf.h
+++ b/arch/sh/include/asm/elf.h
@@ -183,7 +183,8 @@ do {									\
 } while (0)
 #endif
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX_32BIT)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX_32BIT | (current->personality & (~PER_MASK)))
 
 #ifdef CONFIG_VSYSCALL
 /* vDSO has arch_setup_additional_pages */
diff --git a/arch/sparc/include/asm/elf_32.h b/arch/sparc/include/asm/elf_32.h
index 2d4d755..ac74a2c 100644
--- a/arch/sparc/include/asm/elf_32.h
+++ b/arch/sparc/include/asm/elf_32.h
@@ -128,6 +128,7 @@ typedef struct {
 
 #define ELF_PLATFORM	(NULL)
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX | (current->personality & (~PER_MASK)))
 
 #endif /* !(__ASMSPARC_ELF_H) */
diff --git a/arch/xtensa/include/asm/elf.h b/arch/xtensa/include/asm/elf.h
index 6e65ead..5293312 100644
--- a/arch/xtensa/include/asm/elf.h
+++ b/arch/xtensa/include/asm/elf.h
@@ -189,7 +189,8 @@ typedef struct {
 #endif
 } elf_xtregs_t;
 
-#define SET_PERSONALITY(ex) set_personality(PER_LINUX_32BIT)
+#define SET_PERSONALITY(ex) \
+	set_personality(PER_LINUX_32BIT | (current->personality & (~PER_MASK)))
 
 struct task_struct;