From: Christoph Hellwig <hch@lst.de> To: Andrew Morton <akpm@linux-foundation.org>, Alexander Viro <viro@zeniv.linux.org.uk> Cc: Jeremy Kerr <jk@ozlabs.org>, Arnd Bergmann <arnd@arndb.de>, "Eric W . Biederman" <ebiederm@xmission.com>, linuxppc-dev@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 3/8] signal: replace __copy_siginfo_to_user32 with to_compat_siginfo Date: Tue, 14 Apr 2020 09:01:37 +0200 [thread overview] Message-ID: <20200414070142.288696-4-hch@lst.de> (raw) In-Reply-To: <20200414070142.288696-1-hch@lst.de> Move copying the siginfo to userspace into the callers, so that the compat_siginfo conversion can be reused by the ELF coredump code without set_fs magic. Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/x86/ia32/ia32_signal.c | 4 +- arch/x86/kernel/signal.c | 5 ++- include/linux/compat.h | 4 +- kernel/signal.c | 89 ++++++++++++++++++------------------- 4 files changed, 52 insertions(+), 50 deletions(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index 2bf188942d5c..0fbaed2562bc 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -301,6 +301,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, compat_sigset_t *set, struct pt_regs *regs) { struct rt_sigframe_ia32 __user *frame; + struct compat_siginfo new; void __user *restorer; void __user *fp = NULL; @@ -350,7 +351,8 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, unsafe_put_user(*(__u64 *)set, (__u64 *)&frame->uc.uc_sigmask, Efault); user_access_end(); - if (__copy_siginfo_to_user32(&frame->info, &ksig->info, SA_IA32_ABI)) + to_compat_siginfo(&new, &ksig->info, SA_IA32_ABI); + if (copy_to_user(&frame->info, &new, sizeof(frame->info))) return -EFAULT; /* Set up registers for signal handler */ diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index bbd451631790..6ff1265f071b 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -517,6 +517,7 @@ static int x32_setup_rt_frame(struct ksignal *ksig, { #ifdef CONFIG_X86_X32_ABI struct rt_sigframe_x32 __user *frame; + struct compat_siginfo new; unsigned long uc_flags; void __user *restorer; void __user *fp = NULL; @@ -543,8 +544,8 @@ static int x32_setup_rt_frame(struct ksignal *ksig, user_access_end(); if (ksig->ka.sa.sa_flags & SA_SIGINFO) { - if (__copy_siginfo_to_user32(&frame->info, &ksig->info, - SA_X32_ABI)) + to_compat_siginfo(&new, &ksig->info, SA_X32_ABI); + if (copy_to_user(&frame->info, &new, sizeof(frame->info))) return -EFAULT; } diff --git a/include/linux/compat.h b/include/linux/compat.h index 14eec6116110..218ebba1e454 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -404,8 +404,8 @@ long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask, unsigned long bitmap_size); int copy_siginfo_from_user32(kernel_siginfo_t *to, const struct compat_siginfo __user *from); int copy_siginfo_to_user32(struct compat_siginfo __user *to, const kernel_siginfo_t *from); -int __copy_siginfo_to_user32(struct compat_siginfo __user *to, - const kernel_siginfo_t *from, unsigned int flags); +void to_compat_siginfo(struct compat_siginfo *to, + const struct kernel_siginfo *from, unsigned int flags); int get_compat_sigevent(struct sigevent *event, const struct compat_sigevent __user *u_event); diff --git a/kernel/signal.c b/kernel/signal.c index 092fee008242..0f3e7fded3a5 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3235,88 +3235,82 @@ int copy_siginfo_from_user(kernel_siginfo_t *to, const siginfo_t __user *from) } #ifdef CONFIG_COMPAT -int __copy_siginfo_to_user32(struct compat_siginfo __user *to, +void to_compat_siginfo(struct compat_siginfo *to, const struct kernel_siginfo *from, unsigned int flags) { - struct compat_siginfo new; - memset(&new, 0, sizeof(new)); + memset(to, 0, sizeof(*to)); + to->si_signo = from->si_signo; + to->si_errno = from->si_errno; + to->si_code = from->si_code; - new.si_signo = from->si_signo; - new.si_errno = from->si_errno; - new.si_code = from->si_code; - switch(siginfo_layout(from->si_signo, from->si_code)) { + switch (siginfo_layout(from->si_signo, from->si_code)) { case SIL_KILL: - new.si_pid = from->si_pid; - new.si_uid = from->si_uid; + to->si_pid = from->si_pid; + to->si_uid = from->si_uid; break; case SIL_TIMER: - new.si_tid = from->si_tid; - new.si_overrun = from->si_overrun; - new.si_int = from->si_int; + to->si_tid = from->si_tid; + to->si_overrun = from->si_overrun; + to->si_int = from->si_int; break; case SIL_POLL: - new.si_band = from->si_band; - new.si_fd = from->si_fd; + to->si_band = from->si_band; + to->si_fd = from->si_fd; break; case SIL_FAULT: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif break; case SIL_FAULT_MCEERR: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif - new.si_addr_lsb = from->si_addr_lsb; + to->si_addr_lsb = from->si_addr_lsb; break; case SIL_FAULT_BNDERR: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif - new.si_lower = ptr_to_compat(from->si_lower); - new.si_upper = ptr_to_compat(from->si_upper); + to->si_lower = ptr_to_compat(from->si_lower); + to->si_upper = ptr_to_compat(from->si_upper); break; case SIL_FAULT_PKUERR: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif - new.si_pkey = from->si_pkey; + to->si_pkey = from->si_pkey; break; case SIL_CHLD: - new.si_pid = from->si_pid; - new.si_uid = from->si_uid; - new.si_status = from->si_status; + to->si_pid = from->si_pid; + to->si_uid = from->si_uid; + to->si_status = from->si_status; #ifdef CONFIG_X86_X32_ABI if (flags & SA_X32_ABI) { - new._sifields._sigchld_x32._utime = from->si_utime; - new._sifields._sigchld_x32._stime = from->si_stime; + to->_sifields._sigchld_x32._utime = from->si_utime; + to->_sifields._sigchld_x32._stime = from->si_stime; } else #endif { - new.si_utime = from->si_utime; - new.si_stime = from->si_stime; + to->si_utime = from->si_utime; + to->si_stime = from->si_stime; } break; case SIL_RT: - new.si_pid = from->si_pid; - new.si_uid = from->si_uid; - new.si_int = from->si_int; + to->si_pid = from->si_pid; + to->si_uid = from->si_uid; + to->si_int = from->si_int; break; case SIL_SYS: - new.si_call_addr = ptr_to_compat(from->si_call_addr); - new.si_syscall = from->si_syscall; - new.si_arch = from->si_arch; + to->si_call_addr = ptr_to_compat(from->si_call_addr); + to->si_syscall = from->si_syscall; + to->si_arch = from->si_arch; break; } - - if (copy_to_user(to, &new, sizeof(struct compat_siginfo))) - return -EFAULT; - - return 0; } #ifndef compat_siginfo_flags @@ -3326,7 +3320,12 @@ int __copy_siginfo_to_user32(struct compat_siginfo __user *to, int copy_siginfo_to_user32(struct compat_siginfo __user *to, const struct kernel_siginfo *from) { - return __copy_siginfo_to_user32(to, from, compat_siginfo_flags()); + struct compat_siginfo new; + + to_compat_siginfo(&new, from, compat_siginfo_flags()); + if (copy_to_user(to, &new, sizeof(*to))) + return -EFAULT; + return 0; } static int post_copy_siginfo_from_user32(kernel_siginfo_t *to, -- 2.25.1
WARNING: multiple messages have this Message-ID (diff)
From: Christoph Hellwig <hch@lst.de> To: Andrew Morton <akpm@linux-foundation.org>, Alexander Viro <viro@zeniv.linux.org.uk> Cc: Arnd Bergmann <arnd@arndb.de>, linux-kernel@vger.kernel.org, Jeremy Kerr <jk@ozlabs.org>, linux-fsdevel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, "Eric W . Biederman" <ebiederm@xmission.com> Subject: [PATCH 3/8] signal: replace __copy_siginfo_to_user32 with to_compat_siginfo Date: Tue, 14 Apr 2020 09:01:37 +0200 [thread overview] Message-ID: <20200414070142.288696-4-hch@lst.de> (raw) In-Reply-To: <20200414070142.288696-1-hch@lst.de> Move copying the siginfo to userspace into the callers, so that the compat_siginfo conversion can be reused by the ELF coredump code without set_fs magic. Signed-off-by: Christoph Hellwig <hch@lst.de> --- arch/x86/ia32/ia32_signal.c | 4 +- arch/x86/kernel/signal.c | 5 ++- include/linux/compat.h | 4 +- kernel/signal.c | 89 ++++++++++++++++++------------------- 4 files changed, 52 insertions(+), 50 deletions(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index 2bf188942d5c..0fbaed2562bc 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -301,6 +301,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, compat_sigset_t *set, struct pt_regs *regs) { struct rt_sigframe_ia32 __user *frame; + struct compat_siginfo new; void __user *restorer; void __user *fp = NULL; @@ -350,7 +351,8 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, unsafe_put_user(*(__u64 *)set, (__u64 *)&frame->uc.uc_sigmask, Efault); user_access_end(); - if (__copy_siginfo_to_user32(&frame->info, &ksig->info, SA_IA32_ABI)) + to_compat_siginfo(&new, &ksig->info, SA_IA32_ABI); + if (copy_to_user(&frame->info, &new, sizeof(frame->info))) return -EFAULT; /* Set up registers for signal handler */ diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index bbd451631790..6ff1265f071b 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -517,6 +517,7 @@ static int x32_setup_rt_frame(struct ksignal *ksig, { #ifdef CONFIG_X86_X32_ABI struct rt_sigframe_x32 __user *frame; + struct compat_siginfo new; unsigned long uc_flags; void __user *restorer; void __user *fp = NULL; @@ -543,8 +544,8 @@ static int x32_setup_rt_frame(struct ksignal *ksig, user_access_end(); if (ksig->ka.sa.sa_flags & SA_SIGINFO) { - if (__copy_siginfo_to_user32(&frame->info, &ksig->info, - SA_X32_ABI)) + to_compat_siginfo(&new, &ksig->info, SA_X32_ABI); + if (copy_to_user(&frame->info, &new, sizeof(frame->info))) return -EFAULT; } diff --git a/include/linux/compat.h b/include/linux/compat.h index 14eec6116110..218ebba1e454 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -404,8 +404,8 @@ long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask, unsigned long bitmap_size); int copy_siginfo_from_user32(kernel_siginfo_t *to, const struct compat_siginfo __user *from); int copy_siginfo_to_user32(struct compat_siginfo __user *to, const kernel_siginfo_t *from); -int __copy_siginfo_to_user32(struct compat_siginfo __user *to, - const kernel_siginfo_t *from, unsigned int flags); +void to_compat_siginfo(struct compat_siginfo *to, + const struct kernel_siginfo *from, unsigned int flags); int get_compat_sigevent(struct sigevent *event, const struct compat_sigevent __user *u_event); diff --git a/kernel/signal.c b/kernel/signal.c index 092fee008242..0f3e7fded3a5 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3235,88 +3235,82 @@ int copy_siginfo_from_user(kernel_siginfo_t *to, const siginfo_t __user *from) } #ifdef CONFIG_COMPAT -int __copy_siginfo_to_user32(struct compat_siginfo __user *to, +void to_compat_siginfo(struct compat_siginfo *to, const struct kernel_siginfo *from, unsigned int flags) { - struct compat_siginfo new; - memset(&new, 0, sizeof(new)); + memset(to, 0, sizeof(*to)); + to->si_signo = from->si_signo; + to->si_errno = from->si_errno; + to->si_code = from->si_code; - new.si_signo = from->si_signo; - new.si_errno = from->si_errno; - new.si_code = from->si_code; - switch(siginfo_layout(from->si_signo, from->si_code)) { + switch (siginfo_layout(from->si_signo, from->si_code)) { case SIL_KILL: - new.si_pid = from->si_pid; - new.si_uid = from->si_uid; + to->si_pid = from->si_pid; + to->si_uid = from->si_uid; break; case SIL_TIMER: - new.si_tid = from->si_tid; - new.si_overrun = from->si_overrun; - new.si_int = from->si_int; + to->si_tid = from->si_tid; + to->si_overrun = from->si_overrun; + to->si_int = from->si_int; break; case SIL_POLL: - new.si_band = from->si_band; - new.si_fd = from->si_fd; + to->si_band = from->si_band; + to->si_fd = from->si_fd; break; case SIL_FAULT: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif break; case SIL_FAULT_MCEERR: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif - new.si_addr_lsb = from->si_addr_lsb; + to->si_addr_lsb = from->si_addr_lsb; break; case SIL_FAULT_BNDERR: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif - new.si_lower = ptr_to_compat(from->si_lower); - new.si_upper = ptr_to_compat(from->si_upper); + to->si_lower = ptr_to_compat(from->si_lower); + to->si_upper = ptr_to_compat(from->si_upper); break; case SIL_FAULT_PKUERR: - new.si_addr = ptr_to_compat(from->si_addr); + to->si_addr = ptr_to_compat(from->si_addr); #ifdef __ARCH_SI_TRAPNO - new.si_trapno = from->si_trapno; + to->si_trapno = from->si_trapno; #endif - new.si_pkey = from->si_pkey; + to->si_pkey = from->si_pkey; break; case SIL_CHLD: - new.si_pid = from->si_pid; - new.si_uid = from->si_uid; - new.si_status = from->si_status; + to->si_pid = from->si_pid; + to->si_uid = from->si_uid; + to->si_status = from->si_status; #ifdef CONFIG_X86_X32_ABI if (flags & SA_X32_ABI) { - new._sifields._sigchld_x32._utime = from->si_utime; - new._sifields._sigchld_x32._stime = from->si_stime; + to->_sifields._sigchld_x32._utime = from->si_utime; + to->_sifields._sigchld_x32._stime = from->si_stime; } else #endif { - new.si_utime = from->si_utime; - new.si_stime = from->si_stime; + to->si_utime = from->si_utime; + to->si_stime = from->si_stime; } break; case SIL_RT: - new.si_pid = from->si_pid; - new.si_uid = from->si_uid; - new.si_int = from->si_int; + to->si_pid = from->si_pid; + to->si_uid = from->si_uid; + to->si_int = from->si_int; break; case SIL_SYS: - new.si_call_addr = ptr_to_compat(from->si_call_addr); - new.si_syscall = from->si_syscall; - new.si_arch = from->si_arch; + to->si_call_addr = ptr_to_compat(from->si_call_addr); + to->si_syscall = from->si_syscall; + to->si_arch = from->si_arch; break; } - - if (copy_to_user(to, &new, sizeof(struct compat_siginfo))) - return -EFAULT; - - return 0; } #ifndef compat_siginfo_flags @@ -3326,7 +3320,12 @@ int __copy_siginfo_to_user32(struct compat_siginfo __user *to, int copy_siginfo_to_user32(struct compat_siginfo __user *to, const struct kernel_siginfo *from) { - return __copy_siginfo_to_user32(to, from, compat_siginfo_flags()); + struct compat_siginfo new; + + to_compat_siginfo(&new, from, compat_siginfo_flags()); + if (copy_to_user(to, &new, sizeof(*to))) + return -EFAULT; + return 0; } static int post_copy_siginfo_from_user32(kernel_siginfo_t *to, -- 2.25.1
next prev parent reply other threads:[~2020-04-14 7:02 UTC|newest] Thread overview: 65+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-04-14 7:01 remove set_fs calls from the exec and coredump code v2 Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-14 7:01 ` [PATCH 1/8] powerpc/spufs: simplify spufs core dumping Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-14 7:01 ` [PATCH 2/8] signal: clean up __copy_siginfo_to_user32 Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-17 21:08 ` Eric W. Biederman 2020-04-17 21:08 ` Eric W. Biederman 2020-04-17 21:09 ` [PATCH 1/2] signal: Factor copy_siginfo_to_external32 from copy_siginfo_to_user32 Eric W. Biederman 2020-04-17 21:09 ` Eric W. Biederman 2020-04-18 8:05 ` Christophe Leroy 2020-04-18 11:55 ` Eric W. Biederman 2020-04-18 11:55 ` Eric W. Biederman 2020-04-19 8:13 ` Christoph Hellwig 2020-04-19 8:13 ` Christoph Hellwig 2020-04-19 9:46 ` Christophe Leroy 2020-04-19 9:54 ` Christophe Leroy 2020-04-19 8:05 ` Christoph Hellwig 2020-04-19 8:05 ` Christoph Hellwig 2020-04-17 21:09 ` [PATCH 2/2] signal: Remove the set_fs in binfmt_elf.c:fill_siginfo_note Eric W. Biederman 2020-04-17 21:09 ` Eric W. Biederman 2020-04-19 8:03 ` [PATCH 2/8] signal: clean up __copy_siginfo_to_user32 Christoph Hellwig 2020-04-19 8:03 ` Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig [this message] 2020-04-14 7:01 ` [PATCH 3/8] signal: replace __copy_siginfo_to_user32 with to_compat_siginfo Christoph Hellwig 2020-04-14 14:00 ` Arnd Bergmann 2020-04-14 14:00 ` Arnd Bergmann 2020-04-14 7:01 ` [PATCH 4/8] binfmt_elf: open code copy_siginfo_to_user to kernelspace buffer Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-14 13:15 ` Arnd Bergmann 2020-04-14 13:15 ` Arnd Bergmann 2020-04-15 7:45 ` Christoph Hellwig 2020-04-15 7:45 ` Christoph Hellwig 2020-04-15 8:20 ` Arnd Bergmann 2020-04-15 8:20 ` Arnd Bergmann 2020-04-17 13:27 ` Christoph Hellwig 2020-04-17 13:27 ` Christoph Hellwig 2020-04-17 18:10 ` Eric W. Biederman 2020-04-17 18:10 ` Eric W. Biederman 2020-04-17 20:06 ` Arnd Bergmann 2020-04-17 20:06 ` Arnd Bergmann 2020-04-15 3:01 ` Michael Ellerman 2020-04-15 3:01 ` Michael Ellerman 2020-04-15 6:19 ` Christoph Hellwig 2020-04-15 6:19 ` Christoph Hellwig 2020-04-14 7:01 ` [PATCH 5/8] binfmt_elf: remove the set_fs(KERNEL_DS) in elf_core_dump Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-14 7:01 ` [PATCH 6/8] binfmt_elf_fdpic: remove the set_fs(KERNEL_DS) in elf_fdpic_core_dump Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-14 7:01 ` [PATCH 7/8] exec: simplify the copy_strings_kernel calling convention Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-14 7:01 ` [PATCH 8/8] exec: open code copy_string_kernel Christoph Hellwig 2020-04-14 7:01 ` Christoph Hellwig 2020-04-18 8:15 ` Christophe Leroy 2020-04-18 8:15 ` Christophe Leroy 2020-04-19 8:06 ` Christoph Hellwig 2020-04-19 8:06 ` Christoph Hellwig 2020-04-19 9:44 ` Christophe Leroy 2020-04-19 9:44 ` Christophe Leroy 2020-04-17 22:41 ` remove set_fs calls from the exec and coredump code v2 Eric W. Biederman 2020-04-17 22:41 ` Eric W. Biederman 2020-04-19 8:19 ` Christoph Hellwig 2020-04-19 8:19 ` Christoph Hellwig 2020-04-19 11:50 ` Eric W. Biederman 2020-04-19 11:50 ` Eric W. Biederman
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