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 3b3159b710d4..e2c328739808 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 e6c6812a9abd..14bc98ff668f 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 f4552db20b4a..32b997126adf 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 8a3d8e2b33c1..8182f2dc89d0 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 c3819804a74b..9ccbc80f0b11 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 c24fa250d653..41193c396bff 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 37976a0d3650..82b499621e05 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 b8da7d0574d2..70896161c636 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 e9b7cda59744..f83c1d0a87cf 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 834849f59ae8..640ddd4b6a9b 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 8157c9267f42..4ebd6b3a0a1e 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 a8fe2c513070..225a7ff320ad 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 f478ce94181f..5d566c7a0af2 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 f38112be67d2..37924afa8d8a 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 2d4d755cba9e..ac74a2c98e6d 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 6e65eadaae14..5293312bc6a4 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;