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 2/7] signal: factor copy_siginfo_to_external32 from copy_siginfo_to_user32 Date: Tue, 21 Apr 2020 17:41:59 +0200 Message-ID: <20200421154204.252921-3-hch@lst.de> (raw) In-Reply-To: <20200421154204.252921-1-hch@lst.de> From: "Eric W. Biederman" <ebiederm@xmission.com> To remove the use of set_fs in the coredump code there needs to be a way to convert a kernel siginfo to a userspace compat siginfo. Call that function copy_siginfo_to_compat and factor it out of copy_siginfo_to_user32. The existence of x32 complicates this code. On x32 SIGCHLD uses 64bit times for utime and stime. As only SIGCHLD is affected and SIGCHLD never causes a coredump I have avoided handling that case. Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Christoph Hellwig <hch@lst.de> --- include/linux/compat.h | 2 + kernel/signal.c | 109 +++++++++++++++++++++++------------------ 2 files changed, 64 insertions(+), 47 deletions(-) diff --git a/include/linux/compat.h b/include/linux/compat.h index 0480ba4db592..adbfe8f688d9 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -402,6 +402,8 @@ long compat_get_bitmap(unsigned long *mask, const compat_ulong_t __user *umask, unsigned long bitmap_size); long compat_put_bitmap(compat_ulong_t __user *umask, unsigned long *mask, unsigned long bitmap_size); +void copy_siginfo_to_external32(struct compat_siginfo *to, + const struct kernel_siginfo *from); 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 get_compat_sigevent(struct sigevent *event, diff --git a/kernel/signal.c b/kernel/signal.c index 713104884414..d8eb30914771 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3231,94 +3231,109 @@ 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, - const struct kernel_siginfo *from) -#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION) -{ - return __copy_siginfo_to_user32(to, from, in_x32_syscall()); -} -int __copy_siginfo_to_user32(struct compat_siginfo __user *to, - const struct kernel_siginfo *from, bool x32_ABI) -#endif +void copy_siginfo_to_external32(struct compat_siginfo *to, + const struct kernel_siginfo *from) { - struct compat_siginfo new; - memset(&new, 0, sizeof(new)); + /* + * This function does not work properly for SIGCHLD on x32, + * but it does not need to as SIGCHLD never causes a coredump. + */ + memset(to, 0, sizeof(*to)); - new.si_signo = from->si_signo; - new.si_errno = from->si_errno; - new.si_code = from->si_code; + to->si_signo = from->si_signo; + to->si_errno = from->si_errno; + to->si_code = 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; + to->si_utime = from->si_utime; + to->si_stime = from->si_stime; #ifdef CONFIG_X86_X32_ABI if (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; } 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; } +} + +int copy_siginfo_to_user32(struct compat_siginfo __user *to, + const struct kernel_siginfo *from) +#if defined(CONFIG_X86_X32_ABI) || defined(CONFIG_IA32_EMULATION) +{ + return __copy_siginfo_to_user32(to, from, in_x32_syscall()); +} +int __copy_siginfo_to_user32(struct compat_siginfo __user *to, + const struct kernel_siginfo *from, bool x32_ABI) +#endif +{ + struct compat_siginfo new; + copy_siginfo_to_external32(&new, from); +#ifdef CONFIG_X86_X32_ABI + if (x32_ABI && from->si_signo == SIGCHLD) { + new._sifields._sigchld_x32._utime = from->si_utime; + new._sifields._sigchld_x32._stime = from->si_stime; + } +#endif if (copy_to_user(to, &new, sizeof(struct compat_siginfo))) return -EFAULT; - return 0; } -- 2.26.1
next prev parent reply index Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top 2020-04-21 15:41 remove set_fs calls from the exec and coredump code v3 Christoph Hellwig 2020-04-21 15:41 ` [PATCH 1/7] powerpc/spufs: simplify spufs core dumping Christoph Hellwig 2020-04-21 18:49 ` Al Viro 2020-04-21 19:01 ` Christoph Hellwig 2020-04-21 19:19 ` Al Viro 2020-04-21 19:25 ` Al Viro 2020-04-21 15:41 ` Christoph Hellwig [this message] 2020-04-26 4:47 ` [PATCH 2/7] signal: factor copy_siginfo_to_external32 from copy_siginfo_to_user32 Andrew Morton 2020-04-26 7:40 ` Christoph Hellwig 2020-04-27 22:40 ` Andrew Morton 2020-04-28 7:09 ` Christoph Hellwig 2020-04-28 7:45 ` Christophe Leroy 2020-04-28 7:48 ` Christoph Hellwig 2020-04-28 19:56 ` [PATCH] fixup! " Arnd Bergmann 2020-04-29 6:17 ` Christophe Leroy 2020-04-29 6:29 ` Christoph Hellwig 2020-04-29 6:44 ` Christoph Hellwig 2020-04-29 8:07 ` Arnd Bergmann 2020-04-29 9:42 ` Christoph Hellwig 2020-04-29 11:28 ` Arnd Bergmann 2020-04-29 11:53 ` Christoph Hellwig 2020-04-29 12:34 ` Arnd Bergmann 2020-04-21 15:42 ` [PATCH 3/7] binfmt_elf: femove the set_fs in fill_siginfo_note Christoph Hellwig 2020-04-21 15:42 ` [PATCH 4/7] binfmt_elf: remove the set_fs(KERNEL_DS) in elf_core_dump Christoph Hellwig 2020-04-21 15:42 ` [PATCH 5/7] binfmt_elf_fdpic: remove the set_fs(KERNEL_DS) in elf_fdpic_core_dump Christoph Hellwig 2020-04-21 15:42 ` [PATCH 6/7] exec: simplify the copy_strings_kernel calling convention Christoph Hellwig 2020-04-21 15:42 ` [PATCH 7/7] exec: open code copy_string_kernel Christoph Hellwig
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20200421154204.252921-3-hch@lst.de \ --to=hch@lst.de \ --cc=akpm@linux-foundation.org \ --cc=arnd@arndb.de \ --cc=ebiederm@xmission.com \ --cc=jk@ozlabs.org \ --cc=linux-fsdevel@vger.kernel.org \ --cc=linux-kernel@vger.kernel.org \ --cc=linuxppc-dev@lists.ozlabs.org \ --cc=viro@zeniv.linux.org.uk \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: link
Linux-Fsdevel Archive on lore.kernel.org Archives are clonable: git clone --mirror https://lore.kernel.org/linux-fsdevel/0 linux-fsdevel/git/0.git # If you have public-inbox 1.1+ installed, you may # initialize and index your mirror using the following commands: public-inbox-init -V2 linux-fsdevel linux-fsdevel/ https://lore.kernel.org/linux-fsdevel \ linux-fsdevel@vger.kernel.org public-inbox-index linux-fsdevel Example config snippet for mirrors Newsgroup available over NNTP: nntp://nntp.lore.kernel.org/org.kernel.vger.linux-fsdevel AGPL code for this site: git clone https://public-inbox.org/public-inbox.git