| From 45a66bcc1ce4817b0b62cc7f0d7c3f551ac67959 Mon Sep 17 00:00:00 2001 |
| From: Stephen Boyd <swboyd@chromium.org> |
| Date: Tue, 8 Mar 2022 18:40:43 -0800 |
| Subject: [PATCH] CHROMIUM: alt-syscall: Mark things const and __init |
| |
| Most of this code runs at init time and the tables in here are not |
| modified, instead they're copied. Let's mark various tables as const |
| (more RO data) and also add __init to functions that run during boot. |
| This should reduce the amount of code resident after boot and allow data |
| tables to be marked read only. |
| |
| BUG=None |
| TEST=Run arc++ on trogdor-kernelnext |
| |
| Signed-off-by: Stephen Boyd <swboyd@chromium.org> |
| Change-Id: I68935c75146be60556195fc4d98774b146ad739c |
| Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/3511418 |
| Reviewed-by: Micah Morton <mortonm@chromium.org> |
| --- |
| arch/arm64/kernel/alt-syscall.c | 2 +- |
| kernel/alt-syscall.c | 3 +-- |
| security/chromiumos/alt-syscall.c | 16 +++++++--------- |
| security/chromiumos/android_whitelists.h | 4 ++-- |
| security/chromiumos/complete_whitelists.h | 4 ++-- |
| security/chromiumos/read_write_test_whitelists.h | 4 ++-- |
| security/chromiumos/third_party_whitelists.h | 4 ++-- |
| 7 files changed, 17 insertions(+), 20 deletions(-) |
| |
| diff --git a/arch/arm64/kernel/alt-syscall.c b/arch/arm64/kernel/alt-syscall.c |
| index 767c5371cf39..c6e30f7817e2 100644 |
| --- a/arch/arm64/kernel/alt-syscall.c |
| +++ b/arch/arm64/kernel/alt-syscall.c |
| @@ -15,7 +15,7 @@ |
| |
| #include <asm/syscall.h> |
| |
| -int arch_dup_sys_call_table(struct alt_sys_call_table *entry) |
| +int __init arch_dup_sys_call_table(struct alt_sys_call_table *entry) |
| { |
| int err; |
| |
| diff --git a/kernel/alt-syscall.c b/kernel/alt-syscall.c |
| index 99599e1506a1..bcf86ad635f7 100644 |
| --- a/kernel/alt-syscall.c |
| +++ b/kernel/alt-syscall.c |
| @@ -28,8 +28,7 @@ |
| static LIST_HEAD(alt_sys_call_tables); |
| static DEFINE_SPINLOCK(alt_sys_call_tables_lock); |
| |
| -/* XXX: there is no "unregister" yet. */ |
| -int register_alt_sys_call_table(struct alt_sys_call_table *entry) |
| +int __init register_alt_sys_call_table(struct alt_sys_call_table *entry) |
| { |
| if (!entry) |
| return -EINVAL; |
| diff --git a/security/chromiumos/alt-syscall.c b/security/chromiumos/alt-syscall.c |
| index 93d410970fe3..41d225267a65 100644 |
| --- a/security/chromiumos/alt-syscall.c |
| +++ b/security/chromiumos/alt-syscall.c |
| @@ -412,7 +412,7 @@ android_compat_clock_adjtime(struct pt_regs *regs) |
| } |
| #endif /* CONFIG_COMPAT */ |
| |
| -static struct syscall_whitelist whitelists[] = { |
| +static const struct syscall_whitelist whitelists[] __initconst = { |
| SYSCALL_WHITELIST(read_write_test), |
| SYSCALL_WHITELIST(android), |
| PERMISSIVE_SYSCALL_WHITELIST(android), |
| @@ -422,8 +422,8 @@ static struct syscall_whitelist whitelists[] = { |
| PERMISSIVE_SYSCALL_WHITELIST(complete) |
| }; |
| |
| -static int alt_syscall_apply_whitelist(const struct syscall_whitelist *wl, |
| - struct alt_sys_call_table *t) |
| +static int __init alt_syscall_apply_whitelist(const struct syscall_whitelist *wl, |
| + struct alt_sys_call_table *t) |
| { |
| unsigned int i; |
| unsigned long *whitelist = kcalloc(BITS_TO_LONGS(t->size), |
| @@ -457,7 +457,7 @@ static int alt_syscall_apply_whitelist(const struct syscall_whitelist *wl, |
| } |
| |
| #ifdef CONFIG_COMPAT |
| -static int |
| +static int __init |
| alt_syscall_apply_compat_whitelist(const struct syscall_whitelist *wl, |
| struct alt_sys_call_table *t) |
| { |
| @@ -492,7 +492,7 @@ alt_syscall_apply_compat_whitelist(const struct syscall_whitelist *wl, |
| return 0; |
| } |
| #else |
| -static inline int |
| +static inline int __init |
| alt_syscall_apply_compat_whitelist(const struct syscall_whitelist *wl, |
| struct alt_sys_call_table *t) |
| { |
| @@ -500,7 +500,7 @@ alt_syscall_apply_compat_whitelist(const struct syscall_whitelist *wl, |
| } |
| #endif /* CONFIG_COMPAT */ |
| |
| -static int alt_syscall_init_one(const struct syscall_whitelist *wl) |
| +static int __init alt_syscall_init_one(const struct syscall_whitelist *wl) |
| { |
| struct alt_sys_call_table *t; |
| int err; |
| @@ -528,10 +528,8 @@ static int alt_syscall_init_one(const struct syscall_whitelist *wl) |
| * Register an alternate syscall table for each whitelist. Note that the |
| * lack of a module_exit() is intentional - once a syscall table is registered |
| * it cannot be unregistered. |
| - * |
| - * TODO(abrestic) Support unregistering syscall tables? |
| */ |
| -static int chromiumos_alt_syscall_init(void) |
| +static int __init chromiumos_alt_syscall_init(void) |
| { |
| unsigned int i; |
| int err; |
| diff --git a/security/chromiumos/android_whitelists.h b/security/chromiumos/android_whitelists.h |
| index 2a17bf124776..e1cb938620a3 100644 |
| --- a/security/chromiumos/android_whitelists.h |
| +++ b/security/chromiumos/android_whitelists.h |
| @@ -55,7 +55,7 @@ static asmlinkage long android_compat_adjtimex(struct pt_regs *regs); |
| static asmlinkage long android_compat_clock_adjtime(struct pt_regs *regs); |
| #endif /* CONFIG_COMPAT */ |
| |
| -static struct syscall_whitelist_entry android_whitelist[] = { |
| +static const struct syscall_whitelist_entry android_whitelist[] __initconst = { |
| SYSCALL_ENTRY(accept), |
| SYSCALL_ENTRY(accept4), |
| SYSCALL_ENTRY_ALT(adjtimex, android_adjtimex), |
| @@ -328,7 +328,7 @@ static struct syscall_whitelist_entry android_whitelist[] = { |
| }; /* end android_whitelist */ |
| |
| #ifdef CONFIG_COMPAT |
| -static struct syscall_whitelist_entry android_compat_whitelist[] = { |
| +static const struct syscall_whitelist_entry android_compat_whitelist[] __initconst = { |
| COMPAT_SYSCALL_ENTRY(access), |
| COMPAT_SYSCALL_ENTRY_ALT(adjtimex, android_compat_adjtimex), |
| COMPAT_SYSCALL_ENTRY(brk), |
| diff --git a/security/chromiumos/complete_whitelists.h b/security/chromiumos/complete_whitelists.h |
| index 224a5d3c6920..493d7ab41d89 100644 |
| --- a/security/chromiumos/complete_whitelists.h |
| +++ b/security/chromiumos/complete_whitelists.h |
| @@ -27,7 +27,7 @@ |
| |
| #include "alt-syscall.h" |
| |
| -static struct syscall_whitelist_entry complete_whitelist[] = { |
| +static const struct syscall_whitelist_entry complete_whitelist[] __initconst = { |
| /* Syscalls wired up on ARM32/ARM64 and x86_64. */ |
| SYSCALL_ENTRY(accept), |
| SYSCALL_ENTRY(accept4), |
| @@ -367,7 +367,7 @@ static struct syscall_whitelist_entry complete_whitelist[] = { |
| * block_syscall() (unless the permissive mode is used in which case the call |
| * will be redirected to warn_compat_syscall()). |
| */ |
| -static struct syscall_whitelist_entry complete_compat_whitelist[] = {}; |
| +static const struct syscall_whitelist_entry complete_compat_whitelist[] __initconst = {}; |
| #endif /* CONFIG_COMPAT */ |
| |
| #endif /* COMPLETE_WHITELISTS_H */ |
| diff --git a/security/chromiumos/read_write_test_whitelists.h b/security/chromiumos/read_write_test_whitelists.h |
| index 5aa7370af4fc..abe939bdb111 100644 |
| --- a/security/chromiumos/read_write_test_whitelists.h |
| +++ b/security/chromiumos/read_write_test_whitelists.h |
| @@ -27,7 +27,7 @@ |
| |
| #include "alt-syscall.h" |
| |
| -static struct syscall_whitelist_entry read_write_test_whitelist[] = { |
| +static const struct syscall_whitelist_entry read_write_test_whitelist[] __initconst = { |
| SYSCALL_ENTRY(exit), |
| SYSCALL_ENTRY(openat), |
| SYSCALL_ENTRY(close), |
| @@ -42,7 +42,7 @@ static struct syscall_whitelist_entry read_write_test_whitelist[] = { |
| }; /* end read_write_test_whitelist */ |
| |
| #ifdef CONFIG_COMPAT |
| -static struct syscall_whitelist_entry read_write_test_compat_whitelist[] = { |
| +static const struct syscall_whitelist_entry read_write_test_compat_whitelist[] __initconst = { |
| COMPAT_SYSCALL_ENTRY(exit), |
| COMPAT_SYSCALL_ENTRY(open), |
| COMPAT_SYSCALL_ENTRY(openat), |
| diff --git a/security/chromiumos/third_party_whitelists.h b/security/chromiumos/third_party_whitelists.h |
| index 7f2582b062bd..c04d2d739b48 100644 |
| --- a/security/chromiumos/third_party_whitelists.h |
| +++ b/security/chromiumos/third_party_whitelists.h |
| @@ -27,7 +27,7 @@ |
| |
| #include "alt-syscall.h" |
| |
| -static struct syscall_whitelist_entry third_party_whitelist[] = { |
| +static const struct syscall_whitelist_entry third_party_whitelist[] __initconst = { |
| SYSCALL_ENTRY(accept), |
| SYSCALL_ENTRY(bind), |
| SYSCALL_ENTRY(brk), |
| @@ -142,7 +142,7 @@ static struct syscall_whitelist_entry third_party_whitelist[] = { |
| }; /* end third_party_whitelist */ |
| |
| #ifdef CONFIG_COMPAT |
| -static struct syscall_whitelist_entry third_party_compat_whitelist[] = { |
| +static const struct syscall_whitelist_entry third_party_compat_whitelist[] __initconst = { |
| COMPAT_SYSCALL_ENTRY(access), |
| COMPAT_SYSCALL_ENTRY(brk), |
| COMPAT_SYSCALL_ENTRY(chdir), |
| -- |
| 2.17.1 |
| |
