From f454322efbf6faee695f517c6b52c4dc03cacd3e Mon Sep 17 00:00:00 2001 From: "Dmitry V. Levin" Date: Tue, 22 Aug 2017 02:16:11 +0300 Subject: signal: replace sigset_to_compat() with put_compat_sigset() There are 4 callers of sigset_to_compat() in the entire kernel. One is in sparc compat rt_sigaction(2), the rest are in kernel/signal.c itself. All are followed by copy_to_user(), and all but the sparc one are under "if it's big-endian..." ifdefs. Let's transform sigset_to_compat() into put_compat_sigset() that also calls copy_to_user(). Suggested-by: Al Viro Signed-off-by: Dmitry V. Levin Signed-off-by: Al Viro --- kernel/signal.c | 27 ++++++--------------------- 1 file changed, 6 insertions(+), 21 deletions(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index 800a18f77732..14ad6bb90dad 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2621,13 +2621,7 @@ COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, if (error) return error; } - if (oset) { - compat_sigset_t old32; - sigset_to_compat(&old32, &old_set); - if (copy_to_user(oset, &old32, sizeof(compat_sigset_t))) - return -EFAULT; - } - return 0; + return oset ? put_compat_sigset(oset, &old_set, sizeof(*oset)) : 0; #else return sys_rt_sigprocmask(how, (sigset_t __user *)nset, (sigset_t __user *)oset, sigsetsize); @@ -2669,20 +2663,11 @@ SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize) COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset, compat_size_t, sigsetsize) { -#ifdef __BIG_ENDIAN sigset_t set; int err = do_sigpending(&set, sigsetsize); - if (!err) { - compat_sigset_t set32; - sigset_to_compat(&set32, &set); - /* we can get here only if sigsetsize <= sizeof(set) */ - if (copy_to_user(uset, &set32, sigsetsize)) - err = -EFAULT; - } + if (!err) + err = put_compat_sigset(uset, &set, sigsetsize); return err; -#else - return sys_rt_sigpending((sigset_t __user *)uset, sigsetsize); -#endif } #endif @@ -3451,7 +3436,6 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, compat_size_t, sigsetsize) { struct k_sigaction new_ka, old_ka; - compat_sigset_t mask; #ifdef __ARCH_HAS_SA_RESTORER compat_uptr_t restorer; #endif @@ -3463,6 +3447,7 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, if (act) { compat_uptr_t handler; + compat_sigset_t mask; ret = get_user(handler, &act->sa_handler); new_ka.sa.sa_handler = compat_ptr(handler); #ifdef __ARCH_HAS_SA_RESTORER @@ -3478,10 +3463,10 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); if (!ret && oact) { - sigset_to_compat(&mask, &old_ka.sa.sa_mask); ret = put_user(ptr_to_compat(old_ka.sa.sa_handler), &oact->sa_handler); - ret |= copy_to_user(&oact->sa_mask, &mask, sizeof(mask)); + ret |= put_compat_sigset(&oact->sa_mask, &old_ka.sa.sa_mask, + sizeof(oact->sa_mask)); ret |= put_user(old_ka.sa.sa_flags, &oact->sa_flags); #ifdef __ARCH_HAS_SA_RESTORER ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer), -- cgit v1.2.3 From 1681634b8c70353d8ca211b9b3443889a16dafeb Mon Sep 17 00:00:00 2001 From: "Dmitry V. Levin" Date: Tue, 22 Aug 2017 02:16:29 +0300 Subject: signal: simplify compat_sigpending() Remove "if it's big-endian..." ifdef in compat_sigpending(), use the endian-agnostic variant. Suggested-by: Al Viro Signed-off-by: Dmitry V. Levin Signed-off-by: Al Viro --- kernel/signal.c | 4 ---- 1 file changed, 4 deletions(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index 14ad6bb90dad..f59c05fc374a 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3330,15 +3330,11 @@ SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set) #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set32) { -#ifdef __BIG_ENDIAN sigset_t set; int err = do_sigpending(&set, sizeof(set.sig[0])); if (!err) err = put_user(set.sig[0], set32); return err; -#else - return sys_rt_sigpending((sigset_t __user *)set32, sizeof(*set32)); -#endif } #endif -- cgit v1.2.3 From 176826af03666758c656dd27f098cc889b71638b Mon Sep 17 00:00:00 2001 From: "Dmitry V. Levin" Date: Tue, 22 Aug 2017 02:16:43 +0300 Subject: signal: lift sigset size check out of do_sigpending() As sigsetsize argument of do_sigpending() is not used anywhere else in that function after the check, remove this argument and move the check out of do_sigpending() into rt_sigpending() and its compat analog. Suggested-by: Al Viro Signed-off-by: Dmitry V. Levin Signed-off-by: Al Viro --- kernel/signal.c | 21 ++++++++++++++------- 1 file changed, 14 insertions(+), 7 deletions(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index f59c05fc374a..9fbc574ced10 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2629,11 +2629,8 @@ COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, } #endif -static int do_sigpending(void *set, unsigned long sigsetsize) +static int do_sigpending(sigset_t *set) { - if (sigsetsize > sizeof(sigset_t)) - return -EINVAL; - spin_lock_irq(¤t->sighand->siglock); sigorsets(set, ¤t->pending.signal, ¤t->signal->shared_pending.signal); @@ -2653,7 +2650,12 @@ static int do_sigpending(void *set, unsigned long sigsetsize) SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize) { sigset_t set; - int err = do_sigpending(&set, sigsetsize); + int err; + + if (sigsetsize > sizeof(*uset)) + return -EINVAL; + + err = do_sigpending(&set); if (!err && copy_to_user(uset, &set, sigsetsize)) err = -EFAULT; return err; @@ -2664,7 +2666,12 @@ COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset, compat_size_t, sigsetsize) { sigset_t set; - int err = do_sigpending(&set, sigsetsize); + int err; + + if (sigsetsize > sizeof(*uset)) + return -EINVAL; + + err = do_sigpending(&set); if (!err) err = put_compat_sigset(uset, &set, sigsetsize); return err; @@ -3331,7 +3338,7 @@ SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set) COMPAT_SYSCALL_DEFINE1(sigpending, compat_old_sigset_t __user *, set32) { sigset_t set; - int err = do_sigpending(&set, sizeof(set.sig[0])); + int err = do_sigpending(&set); if (!err) err = put_user(set.sig[0], set32); return err; -- cgit v1.2.3 From 3968cf623892d710e651070243fd16af312a9797 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 3 Sep 2017 21:45:17 -0400 Subject: get_compat_sigset() similar to put_compat_sigset() Signed-off-by: Al Viro --- kernel/signal.c | 27 ++++----------------------- 1 file changed, 4 insertions(+), 23 deletions(-) (limited to 'kernel/signal.c') diff --git a/kernel/signal.c b/kernel/signal.c index 9fbc574ced10..36a523640894 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2600,7 +2600,6 @@ SYSCALL_DEFINE4(rt_sigprocmask, int, how, sigset_t __user *, nset, COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, compat_sigset_t __user *, oset, compat_size_t, sigsetsize) { -#ifdef __BIG_ENDIAN sigset_t old_set = current->blocked; /* XXX: Don't preclude handling different sized sigset_t's. */ @@ -2608,13 +2607,10 @@ COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, return -EINVAL; if (nset) { - compat_sigset_t new32; sigset_t new_set; int error; - if (copy_from_user(&new32, nset, sizeof(compat_sigset_t))) + if (get_compat_sigset(&new_set, nset)) return -EFAULT; - - sigset_from_compat(&new_set, &new32); sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP)); error = sigprocmask(how, &new_set, NULL); @@ -2622,10 +2618,6 @@ COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset, return error; } return oset ? put_compat_sigset(oset, &old_set, sizeof(*oset)) : 0; -#else - return sys_rt_sigprocmask(how, (sigset_t __user *)nset, - (sigset_t __user *)oset, sigsetsize); -#endif } #endif @@ -2908,7 +2900,6 @@ COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese, struct compat_siginfo __user *, uinfo, struct compat_timespec __user *, uts, compat_size_t, sigsetsize) { - compat_sigset_t s32; sigset_t s; struct timespec t; siginfo_t info; @@ -2917,9 +2908,8 @@ COMPAT_SYSCALL_DEFINE4(rt_sigtimedwait, compat_sigset_t __user *, uthese, if (sigsetsize != sizeof(sigset_t)) return -EINVAL; - if (copy_from_user(&s32, uthese, sizeof(compat_sigset_t))) + if (get_compat_sigset(&s, uthese)) return -EFAULT; - sigset_from_compat(&s, &s32); if (uts) { if (compat_get_timespec(&t, uts)) @@ -3450,18 +3440,16 @@ COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig, if (act) { compat_uptr_t handler; - compat_sigset_t mask; ret = get_user(handler, &act->sa_handler); new_ka.sa.sa_handler = compat_ptr(handler); #ifdef __ARCH_HAS_SA_RESTORER ret |= get_user(restorer, &act->sa_restorer); new_ka.sa.sa_restorer = compat_ptr(restorer); #endif - ret |= copy_from_user(&mask, &act->sa_mask, sizeof(mask)); + ret |= get_compat_sigset(&new_ka.sa.sa_mask, &act->sa_mask); ret |= get_user(new_ka.sa.sa_flags, &act->sa_flags); if (ret) return -EFAULT; - sigset_from_compat(&new_ka.sa.sa_mask, &mask); } ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL); @@ -3649,22 +3637,15 @@ SYSCALL_DEFINE2(rt_sigsuspend, sigset_t __user *, unewset, size_t, sigsetsize) #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_size_t, sigsetsize) { -#ifdef __BIG_ENDIAN sigset_t newset; - compat_sigset_t newset32; /* XXX: Don't preclude handling different sized sigset_t's. */ if (sigsetsize != sizeof(sigset_t)) return -EINVAL; - if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t))) + if (get_compat_sigset(&newset, unewset)) return -EFAULT; - sigset_from_compat(&newset, &newset32); return sigsuspend(&newset); -#else - /* on little-endian bitmaps don't care about granularity */ - return sys_rt_sigsuspend((sigset_t __user *)unewset, sigsetsize); -#endif } #endif -- cgit v1.2.3