[PATCH 10/10] Kconfig: regularize selection of CONFIG_BINFMT_ELF

Al Viro
2020-12-03T21:47:42Z

From: Al Viro <viro@zeniv.linux.org.uk>

with mips converted to use of fs/config_binfmt_elf.c, there's no
need to keep selects of that thing all over arch/* - we can simply
turn into def_bool y if COMPAT && BINFMT_ELF (in fs/Kconfig.binfmt)
and get rid of all selects.

Several architectures got those selects wrong (e.g. you could
end up with sparc64 sans BINFMT_ELF, with select violating
dependencies, or with amd64 with X32 and BINFMT_ELF enabled,
but unable to exec any X32 binaries), etc.

Randy Dunlap has spotted some of those; IMO this is simpler than
his fix, but it depends upon the stuff that would need to be
backported, so we might end up using his variant for -stable.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---
arch/arm64/Kconfig | 1 -
arch/mips/Kconfig | 2 --
arch/parisc/Kconfig | 1 -
arch/powerpc/Kconfig | 1 -
arch/s390/Kconfig | 1 -
arch/sparc/Kconfig | 1 -
arch/x86/Kconfig | 1 -
fs/Kconfig.binfmt | 2 +-
8 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index f858c352f72a..84a0af4ba8d7 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1196,7 +1196,6 @@ config ARM64_TAGGED_ADDR_ABI
menuconfig COMPAT
bool "Kernel support for 32-bit EL0"
depends on ARM64_4K_PAGES || EXPERT
- select COMPAT_BINFMT_ELF if BINFMT_ELF
select HAVE_UID16
select OLD_SIGSUSPEND3
select COMPAT_OLD_SIGACTION
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index f14731aee182..df35ce61aa81 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -3271,7 +3271,6 @@ config MIPS32_O32
select ARCH_WANT_OLD_COMPAT_IPC
select COMPAT
select MIPS32_COMPAT
- select COMPAT_BINFMT_ELF
select SYSVIPC_COMPAT if SYSVIPC
help
Select this option if you want to run o32 binaries. These are pure
@@ -3285,7 +3284,6 @@ config MIPS32_N32
depends on 64BIT
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
select COMPAT
- select COMPAT_BINFMT_ELF
select MIPS32_COMPAT
select SYSVIPC_COMPAT if SYSVIPC
help
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig
index b234e8154cbd..97c233a7445c 100644
--- a/arch/parisc/Kconfig
+++ b/arch/parisc/Kconfig
@@ -336,7 +336,6 @@ source "kernel/Kconfig.hz"
config COMPAT
def_bool y
depends on 64BIT
- select COMPAT_BINFMT_ELF if BINFMT_ELF

config SYSVIPC_COMPAT
def_bool y
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index e9f13fe08492..d27469a024a5 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -278,7 +278,6 @@ config COMPAT
bool "Enable support for 32bit binaries"
depends on PPC64
default y if !CPU_LITTLE_ENDIAN
- select COMPAT_BINFMT_ELF
select ARCH_WANT_OLD_COMPAT_IPC
select COMPAT_OLD_SIGACTION

diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 4a2a12be04c9..55d140044f32 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -426,7 +426,6 @@ config 64BIT
config COMPAT
def_bool y
prompt "Kernel support for 31 bit emulation"
- select COMPAT_BINFMT_ELF if BINFMT_ELF
select ARCH_WANT_OLD_COMPAT_IPC
select COMPAT_OLD_SIGACTION
select HAVE_UID16
diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig
index a6ca135442f9..12943d94fcd0 100644
--- a/arch/sparc/Kconfig
+++ b/arch/sparc/Kconfig
@@ -496,7 +496,6 @@ config COMPAT
bool
depends on SPARC64
default y
- select COMPAT_BINFMT_ELF
select HAVE_UID16
select ARCH_WANT_OLD_COMPAT_IPC
select COMPAT_OLD_SIGACTION
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 8eea77cf53a7..638fdf3e6578 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -2844,7 +2844,6 @@ config IA32_EMULATION
depends on X86_64
select ARCH_WANT_OLD_COMPAT_IPC
select BINFMT_ELF
- select COMPAT_BINFMT_ELF
select COMPAT_OLD_SIGACTION
help
Include code to run legacy 32-bit programs under a
diff --git a/fs/Kconfig.binfmt b/fs/Kconfig.binfmt
index 885da6d983b4..b32f5df68ae9 100644
--- a/fs/Kconfig.binfmt
+++ b/fs/Kconfig.binfmt
@@ -29,7 +29,7 @@ config BINFMT_ELF
latest version).

config COMPAT_BINFMT_ELF
- bool
+ def_bool y
depends on COMPAT && BINFMT_ELF
select ELFCORE

--
2.11.0