Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752337AbeAQHg4 (ORCPT + 1 other); Wed, 17 Jan 2018 02:36:56 -0500 Received: from verein.lst.de ([213.95.11.211]:53192 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750953AbeAQHgy (ORCPT ); Wed, 17 Jan 2018 02:36:54 -0500 Date: Wed, 17 Jan 2018 08:36:52 +0100 From: Christoph Hellwig To: Jeff Moyer Cc: Christoph Hellwig , viro@zeniv.linux.org.uk, Avi Kivity , linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 32/32] aio: implement io_pgetevents Message-ID: <20180117073652.GA27389@lst.de> References: <20180110155853.32348-1-hch@lst.de> <20180110155853.32348-33-hch@lst.de> <20180115085310.GB32532@lst.de> <20180116120433.GA14579@lst.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: On Tue, Jan 16, 2018 at 07:41:24PM -0500, Jeff Moyer wrote: > I'd be willing to bet the issue is in your io_syscall6 implementation. > You pass in arg5 where arg6 should be used. Don't feel bad, it took me > the better part of today to figure that out. :) > > Here's an incremental diff on top of what you've posted. Feel free to > fold it into your patch (and format however you like). You can find the > libaio changes in my 'aio-poll' branch: > https://pagure.io/libaio/commits/aio-poll > > These changes were run through the libaio test harness, 64 bit and 32 > bit, so the compat system call was tested. Oops, yes. Although I prefer the copy_from_user version, this is what I had: diff --git a/fs/aio.c b/fs/aio.c index 9fe0a5539596..6c1bbfa9b06a 100644 --- a/fs/aio.c +++ b/fs/aio.c @@ -1984,8 +1984,9 @@ SYSCALL_DEFINE6(io_pgetevents, long, nr, struct io_event __user *, events, struct timespec __user *, timeout, - const sigset_t __user *, sigmask) + const struct __aio_sigset __user *, usig) { + struct __aio_sigset ksig = { NULL, }; sigset_t ksigmask, sigsaved; struct timespec64 ts; int ret; @@ -1993,8 +1994,13 @@ SYSCALL_DEFINE6(io_pgetevents, if (timeout && unlikely(get_timespec64(&ts, timeout))) return -EFAULT; - if (sigmask) { - if (copy_from_user(&ksigmask, sigmask, sizeof(ksigmask))) + if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) + return -EFAULT; + + if (ksig.sigmask) { + if (ksig.sigsetsize != sizeof(sigset_t)) + return -EINVAL; + if (copy_from_user(&ksigmask, ksig.sigmask, sizeof(ksigmask))) return -EFAULT; sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP)); sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); @@ -2002,7 +2008,7 @@ SYSCALL_DEFINE6(io_pgetevents, ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &ts : NULL); if (signal_pending(current)) { - if (sigmask) { + if (ksig.sigmask) { current->saved_sigmask = sigsaved; set_restore_sigmask(); } @@ -2010,7 +2016,7 @@ SYSCALL_DEFINE6(io_pgetevents, if (!ret) ret = -ERESTARTNOHAND; } else { - if (sigmask) + if (ksig.sigmask) sigprocmask(SIG_SETMASK, &sigsaved, NULL); } @@ -2036,14 +2042,21 @@ COMPAT_SYSCALL_DEFINE5(io_getevents, compat_aio_context_t, ctx_id, return ret; } + +struct __compat_aio_sigset { + compat_sigset_t __user *sigmask; + compat_size_t sigsetsize; +}; + COMPAT_SYSCALL_DEFINE6(io_pgetevents, compat_aio_context_t, ctx_id, compat_long_t, min_nr, compat_long_t, nr, struct io_event __user *, events, struct compat_timespec __user *, timeout, - const compat_sigset_t __user *, sigmask) + const struct __compat_aio_sigset __user *, usig) { + struct __compat_aio_sigset ksig = { NULL, }; sigset_t ksigmask, sigsaved; struct timespec64 t; int ret; @@ -2051,8 +2064,13 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents, if (timeout && compat_get_timespec64(&t, timeout)) return -EFAULT; - if (sigmask) { - if (get_compat_sigset(&ksigmask, sigmask)) + if (usig && copy_from_user(&ksig, usig, sizeof(ksig))) + return -EFAULT; + + if (ksig.sigmask) { + if (ksig.sigsetsize != sizeof(compat_sigset_t)) + return -EINVAL; + if (get_compat_sigset(&ksigmask, ksig.sigmask)) return -EFAULT; sigdelsetmask(&ksigmask, sigmask(SIGKILL) | sigmask(SIGSTOP)); sigprocmask(SIG_SETMASK, &ksigmask, &sigsaved); @@ -2060,14 +2078,14 @@ COMPAT_SYSCALL_DEFINE6(io_pgetevents, ret = do_io_getevents(ctx_id, min_nr, nr, events, timeout ? &t : NULL); if (signal_pending(current)) { - if (sigmask) { + if (ksig.sigmask) { current->saved_sigmask = sigsaved; set_restore_sigmask(); } if (!ret) ret = -ERESTARTNOHAND; } else { - if (sigmask) + if (ksig.sigmask) sigprocmask(SIG_SETMASK, &sigsaved, NULL); } diff --git a/include/linux/compat.h b/include/linux/compat.h index a4cda98073f1..6c04450e961f 100644 --- a/include/linux/compat.h +++ b/include/linux/compat.h @@ -205,6 +205,7 @@ extern int put_compat_rusage(const struct rusage *, struct compat_rusage __user *); struct compat_siginfo; +struct __compat_aio_sigset; extern asmlinkage long compat_sys_waitid(int, compat_pid_t, struct compat_siginfo __user *, int, @@ -541,7 +542,7 @@ asmlinkage long compat_sys_io_pgetevents(compat_aio_context_t ctx_id, compat_long_t nr, struct io_event __user *events, struct compat_timespec __user *timeout, - const compat_sigset_t __user *sigmask); + const struct __compat_aio_sigset __user *usig); asmlinkage long compat_sys_io_submit(compat_aio_context_t ctx_id, int nr, u32 __user *iocb); asmlinkage long compat_sys_mount(const char __user *dev_name, diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 3bc9a130f4a9..8515ec53c81b 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -544,7 +544,7 @@ asmlinkage long sys_io_pgetevents(aio_context_t ctx_id, long nr, struct io_event __user *events, struct timespec __user *timeout, - const sigset_t __user *sigmask); + const struct __aio_sigset *sig); asmlinkage long sys_io_submit(aio_context_t, long, struct iocb __user * __user *); asmlinkage long sys_io_cancel(aio_context_t ctx_id, struct iocb __user *iocb, diff --git a/include/uapi/linux/aio_abi.h b/include/uapi/linux/aio_abi.h index 28330105a4b6..ed0185945bb2 100644 --- a/include/uapi/linux/aio_abi.h +++ b/include/uapi/linux/aio_abi.h @@ -29,6 +29,7 @@ #include #include +#include #include typedef __kernel_ulong_t aio_context_t; @@ -106,5 +107,10 @@ struct iocb { #undef IFBIG #undef IFLITTLE +struct __aio_sigset { + sigset_t __user *sigmask; + size_t sigsetsize; +}; + #endif /* __LINUX__AIO_ABI_H */