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[79.223.159.216]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-42e96a36251sm156842415e9.37.2024.09.30.10.08.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Sep 2024 10:08:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1727716092; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KRiyw0at5DGRgBVyJeLHnY8AwyrMo6ngg550Y6llmjo=; b=dwfPm7WEJs7WnzG8AsMcJ1llr7zkeiakTTKf6BoF5x9yOs6v/VZrKyVF1pJADwwXXunT61 8YW0HT5882/HxAO45YG1VzNIYZXMQ+9flIJYyD/Vx/NioWrnwPOa33m40SdXEQkVk6oHPL rH5CvvPK74a1/0TdIUIQR6YDG7WhEus= X-MC-Unique: G1IVGgumNZu7_gkzPcgcxw-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1727716089; x=1728320889; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=KRiyw0at5DGRgBVyJeLHnY8AwyrMo6ngg550Y6llmjo=; b=pzI5sgrTZKiQs2DNt2wLpjrb7q4/b2OTjExwK4EGjntrThtgNMgrRpN8ewSRx7iur/ 0yc1+hKkWlXl196DSKOa3LrYQ8g3skQHfbg8NmjmEfZ22509mkOEM/ZvnXqSeKCHq+0j DUZ32KITiwzjmXH+uGYtlYT9WuoLweeaWPEkNBIDlKQ384LQalbh4FtYwxChxxCtBiMU ZxXvkUdCCBi4BnyhCmViNw4ccjGQF5mLO2dx/m6IseB9LQqS/thoGqud5IIiTPP1P/6I Gvnjb9XlfyGmgzQf4VTs2eliLdkFhq0Rl6PnoMW/Qv9d+rVuvLj65o6lfj6kuTNKW6eh a1WQ== X-Gm-Message-State: AOJu0YyYLQ+sHn2y7QZFU1OPySzby4qPsCIGG2xjpzd4nzy7PXBSk9jQ Zqjcb7kVorAazjPdhpmbdzAxIenL5K98ge85Ej6LuxPEVdidt1Ek9yPWwJiR5VmmtxC5j6g6FBD Jx+tWNr9Op+nkgV5YAGDsJ5mZKX+LLW5hveYmVgUxyXpoXGf7Jw97hRS+7vDGQceaiRMYw2MD0w n0Z50aysCok1L/Zb1MjQ20euofmo7KgNWQ X-Received: by 2002:a05:600c:1d2a:b0:428:ec2a:8c94 with SMTP id 5b1f17b1804b1-42f58434112mr102934285e9.10.1727716088588; Mon, 30 Sep 2024 10:08:08 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEq69dp95nNBHahJdCCcXf1JlB73PN7Y1Vw+9/UNeDGgUzD9nqwu8hZOHluIzmSkBz8ohWLDg== X-Received: by 2002:a05:600c:1d2a:b0:428:ec2a:8c94 with SMTP id 5b1f17b1804b1-42f58434112mr102933915e9.10.1727716087999; Mon, 30 Sep 2024 10:08:07 -0700 (PDT) From: Michael Vogt To: qemu-devel@nongnu.org Cc: Michael Vogt , Richard Henderson , Laurent Vivier , Michael Vogt Subject: [PATCH v8 1/2] linux-user: add openat2 support in linux-user Date: Mon, 30 Sep 2024 19:07:18 +0200 Message-ID: <1c2c8c9db3731ed4c6fd9b10c63637c3e4caf8f5.1727715697.git.mvogt@redhat.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.129.124; envelope-from=mvogt@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.144, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1727716158674116600 Content-Type: text/plain; charset="utf-8" This commit adds support for the `openat2()` syscall in the `linux-user` userspace emulator. It is implemented by extracting a new helper `maybe_do_fake_open()` out of the exiting `do_guest_openat()` and share that with the new `do_guest_openat2()`. Unfortunately we cannot just make do_guest_openat2() a superset of do_guest_openat() because the openat2() syscall is stricter with the argument checking and will return an error for invalid flags or mode combinations (which open()/openat() will ignore). The implementation is similar to SYSCALL_DEFINE(openat2), i.e. a new `copy_struct_from_user()` is used that works the same as the kernels version to support backwards-compatibility for struct syscall argument. Instead of including openat2.h we create a copy of `open_how` as `open_how_ver0` to ensure that if the structure grows we can log a LOG_UNIMP warning. Note that in this commit using openat2() for a "faked" file in /proc will honor the "resolve" flags for RESOLVE_NO_{MAGIC,SYM}LINKS for path based access to /proc/self/exe (which is the only magic link we support for faked files). Note it will not catch special access via e.g. dirfd. This is not great but it seems similar to the exiting behavior when openat() is called with a dirfd to "/proc". Here too the fake file lookup may not catch the special file because no dirfd is used to determine if the path is in /proc. Signed-off-by: Michael Vogt Buglink: https://github.com/osbuild/bootc-image-builder/issues/619 Reviewed-by: Laurent Vivier --- linux-user/syscall.c | 105 +++++++++++++++++++++++++++++++++++++- linux-user/syscall_defs.h | 13 +++++ 2 files changed, 116 insertions(+), 2 deletions(-) diff --git a/linux-user/syscall.c b/linux-user/syscall.c index a666986189..2febc3bc3f 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -602,6 +602,34 @@ static int check_zeroed_user(abi_long addr, size_t ksi= ze, size_t usize) return 1; } =20 +/* + * Copies a target struct to a host struct, in a way that guarantees + * backwards-compatibility for struct syscall arguments. + * + * Similar to kernels uaccess.h:copy_struct_from_user() + */ +static int +copy_struct_from_user(void *dst, size_t ksize, abi_ptr src, size_t usize) +{ + size_t size =3D MIN(ksize, usize); + size_t rest =3D MAX(ksize, usize) - size; + + /* Deal with trailing bytes. */ + if (usize < ksize) { + memset(dst + size, 0, rest); + } else if (usize > ksize) { + int ret =3D check_zeroed_user(src, ksize, usize); + if (ret <=3D 0) { + return ret ?: -TARGET_E2BIG; + } + } + /* Copy the interoperable parts of the struct. */ + if (copy_from_user(dst, src, size)) { + return -TARGET_EFAULT; + } + return 0; +} + #define safe_syscall0(type, name) \ static type safe_##name(void) \ { \ @@ -653,6 +681,15 @@ safe_syscall3(ssize_t, read, int, fd, void *, buff, si= ze_t, count) safe_syscall3(ssize_t, write, int, fd, const void *, buff, size_t, count) safe_syscall4(int, openat, int, dirfd, const char *, pathname, \ int, flags, mode_t, mode) + +struct open_how_ver0 { + __u64 flags; + __u64 mode; + __u64 resolve; +}; +safe_syscall4(int, openat2, int, dirfd, const char *, pathname, \ + const struct open_how_ver0 *, how, size_t, size) + #if defined(TARGET_NR_wait4) || defined(TARGET_NR_waitpid) safe_syscall4(pid_t, wait4, pid_t, pid, int *, status, int, options, \ struct rusage *, rusage) @@ -8332,8 +8369,9 @@ static int open_net_route(CPUArchState *cpu_env, int = fd) } #endif =20 -int do_guest_openat(CPUArchState *cpu_env, int dirfd, const char *fname, - int flags, mode_t mode, bool safe) +static int maybe_do_fake_open(CPUArchState *cpu_env, int dirfd, + const char *fname, int flags, mode_t mode, + int openat2_resolve, bool safe) { g_autofree char *proc_name =3D NULL; const char *pathname; @@ -8370,6 +8408,12 @@ int do_guest_openat(CPUArchState *cpu_env, int dirfd= , const char *fname, } =20 if (is_proc_myself(pathname, "exe")) { + /* Honor openat2 resolve flags */ + if ((openat2_resolve & RESOLVE_NO_MAGICLINKS) || + (openat2_resolve & RESOLVE_NO_SYMLINKS)) { + errno =3D ELOOP; + return -1; + } if (safe) { return safe_openat(dirfd, exec_path, flags, mode); } else { @@ -8416,6 +8460,17 @@ int do_guest_openat(CPUArchState *cpu_env, int dirfd= , const char *fname, return fd; } =20 + return -2; +} + +int do_guest_openat(CPUArchState *cpu_env, int dirfd, const char *pathname, + int flags, mode_t mode, bool safe) +{ + int fd =3D maybe_do_fake_open(cpu_env, dirfd, pathname, flags, mode, 0= , safe); + if (fd > -2) { + return fd; + } + if (safe) { return safe_openat(dirfd, path(pathname), flags, mode); } else { @@ -8423,6 +8478,49 @@ int do_guest_openat(CPUArchState *cpu_env, int dirfd= , const char *fname, } } =20 + +static int do_openat2(CPUArchState *cpu_env, abi_long dirfd, + abi_ptr guest_pathname, abi_ptr guest_open_how, + abi_ulong guest_size) +{ + struct open_how_ver0 how =3D {0}; + char *pathname; + int ret; + + if (guest_size < sizeof(struct target_open_how_ver0)) { + return -TARGET_EINVAL; + } + ret =3D copy_struct_from_user(&how, sizeof(how), guest_open_how, guest= _size); + if (ret) { + if (ret =3D=3D -TARGET_E2BIG) { + qemu_log_mask(LOG_UNIMP, + "Unimplemented openat2 open_how size: " + TARGET_ABI_FMT_lu "\n", guest_size); + } + return ret; + } + pathname =3D lock_user_string(guest_pathname); + if (!pathname) { + return -TARGET_EFAULT; + } + + how.flags =3D target_to_host_bitmask(tswap64(how.flags), fcntl_flags_t= bl); + how.mode =3D tswap64(how.mode); + how.resolve =3D tswap64(how.resolve); + int fd =3D maybe_do_fake_open(cpu_env, dirfd, pathname, how.flags, how= .mode, + how.resolve, true); + if (fd > -2) { + ret =3D get_errno(fd); + } else { + ret =3D get_errno(safe_openat2(dirfd, pathname, &how, + sizeof(struct open_how_ver0))); + } + + fd_trans_unregister(ret); + unlock_user(pathname, guest_pathname, 0); + return ret; +} + ssize_t do_guest_readlink(const char *pathname, char *buf, size_t bufsiz) { ssize_t ret; @@ -9195,6 +9293,9 @@ static abi_long do_syscall1(CPUArchState *cpu_env, in= t num, abi_long arg1, fd_trans_unregister(ret); unlock_user(p, arg2, 0); return ret; + case TARGET_NR_openat2: + ret =3D do_openat2(cpu_env, arg1, arg2, arg3, arg4); + return ret; #if defined(TARGET_NR_name_to_handle_at) && defined(CONFIG_OPEN_BY_HANDLE) case TARGET_NR_name_to_handle_at: ret =3D do_name_to_handle_at(arg1, arg2, arg3, arg4, arg5); diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h index e08d088740..de5091c977 100644 --- a/linux-user/syscall_defs.h +++ b/linux-user/syscall_defs.h @@ -2748,4 +2748,17 @@ struct target_sched_param { abi_int sched_priority; }; =20 +/* from kernel's include/uapi/linux/openat2.h */ +struct target_open_how_ver0 { + abi_ullong flags; + abi_ullong mode; + abi_ullong resolve; +}; +#ifndef RESOLVE_NO_MAGICLINKS +#define RESOLVE_NO_MAGICLINKS 0x02 +#endif +#ifndef RESOLVE_NO_SYMLINKS +#define RESOLVE_NO_SYMLINKS 0x04 +#endif + #endif --=20 2.45.2 From nobody Sun Nov 24 01:37:05 2024 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; 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[79.223.159.216]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-42e96a36251sm156842415e9.37.2024.09.30.10.08.08 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 30 Sep 2024 10:08:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1727716092; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/gMF25+OQ76L5kMFSaQJWClmZBFiY84FfTl382gIXGg=; b=YbsRbmBGITRYTD+kRglGx1oo2Dp2rj7KI9jsJ/EPDTpOSveyhM7GzUdG6/LrtHzooqO3+s 3bp60IzcRXScGYR7RdyT157tfITx8rsKLQNoSZdViWz8pb8Zrs3o66nSSOoMvRLdml/2+p JgIO7aYJCa5D8Za9MauLQqgZGeijfxM= X-MC-Unique: HsYOZA7iMkuI99KTcA2O0Q-1 X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1727716089; x=1728320889; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/gMF25+OQ76L5kMFSaQJWClmZBFiY84FfTl382gIXGg=; b=LxmLoRLx/sw7FEicmMp/bM/fZAM30zuBUQGsp33hn4j6L9KiV68fwOp7wgLFZRIelJ j8SQ3dO3Zmo+5k+7nyA2oTZ2dblJFXBvbW6jXHzSQZK1cMtetzNqsv+aF2kTGQcbXe8d MjvAosdpCWvyMVoQsWAHvB8ypChCdqqsLkjSs+h9fOuqU5ew8VLXYHsnoHR6qUmzcbQ6 LGUpWeP8hTOL8CI5sE37TviA4bhMs3EXPUKh0HVqZn4n9wWPf3fxfd7aXCCvcW8Tphx0 6aQmf83wdj4WTN1ApHB8leRyvHF32YUaK0TZph7muySF85imthZsebO0VTcsphuubiLx XuEg== X-Gm-Message-State: AOJu0YxFFbnvOreJWEkwCN16U+c3X13hbyPw+oARlrX0Y6VQDswfXXGl dAEKVKn/9C+MEx6bMTXjlmmcQGMPRoPc853U1qLcSDRmwscWG7mXIxWnqyXRU8vuuShWZyDWCEY FV34QZm37mUKrG+sHJHFNE/FXDc+xHUncww9lcMgRt0iWB/lGS7bwzmNokClr99T0IPAzJPy1iX KNXt8a2AowjhB8MiO7ZqmkhMN2sWQ5GTfH X-Received: by 2002:adf:e589:0:b0:37c:d183:abd6 with SMTP id ffacd0b85a97d-37cd5a9a255mr6178283f8f.32.1727716089343; Mon, 30 Sep 2024 10:08:09 -0700 (PDT) X-Google-Smtp-Source: AGHT+IHDYxRbGGYxiVQ0XxAulD2olEwWFTDQT5EDwOvgXHoxtOPUm4U9YZsKyhSk65cdjyYe5bknzQ== X-Received: by 2002:adf:e589:0:b0:37c:d183:abd6 with SMTP id ffacd0b85a97d-37cd5a9a255mr6178259f8f.32.1727716088798; Mon, 30 Sep 2024 10:08:08 -0700 (PDT) From: Michael Vogt To: qemu-devel@nongnu.org Cc: Michael Vogt , Richard Henderson , Laurent Vivier , Michael Vogt Subject: [PATCH v8 2/2] linux-user: add strace support for openat2 Date: Mon, 30 Sep 2024 19:07:19 +0200 Message-ID: <4e65ab27fa0eda54034299802cb176ce78db9091.1727715697.git.mvogt@redhat.com> X-Mailer: git-send-email 2.45.2 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Received-SPF: pass (zohomail.com: domain of gnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Received-SPF: pass client-ip=170.10.133.124; envelope-from=mvogt@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -21 X-Spam_score: -2.2 X-Spam_bar: -- X-Spam_report: (-2.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.144, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: qemu-devel-bounces+importer=patchew.org@nongnu.org X-ZohoMail-DKIM: pass (identity @redhat.com) X-ZM-MESSAGEID: 1727716170528116600 Content-Type: text/plain; charset="utf-8" This commit adds support for the `openat2()` to `QEMU_STRACE`. It will use the `openat2.h` header if available to create user readable flags for the `resolve` argument but does not require the header otherwise. It also makes `copy_struct_from_user()` available via `qemu.h` and `open_how_ver0` via `syscall_defs.h` so that strace.c can use them. Signed-off-by: Michael Vogt --- linux-user/qemu.h | 9 +++++++++ linux-user/strace.c | 40 +++++++++++++++++++++++++++++++++++++++ linux-user/strace.list | 3 +++ linux-user/syscall.c | 8 +------- linux-user/syscall_defs.h | 5 +++++ meson.build | 1 + 6 files changed, 59 insertions(+), 7 deletions(-) diff --git a/linux-user/qemu.h b/linux-user/qemu.h index 2e90a97175..98ad848ab2 100644 --- a/linux-user/qemu.h +++ b/linux-user/qemu.h @@ -313,6 +313,15 @@ static inline bool access_ok(CPUState *cpu, int type, int copy_from_user(void *hptr, abi_ulong gaddr, ssize_t len); int copy_to_user(abi_ulong gaddr, void *hptr, ssize_t len); =20 +/* + * copy_struct_from_user() copies a target struct to a host struct, in + * a way that guarantees backwards-compatibility for struct syscall + * arguments. + * + * Similar to kernels uaccess.h:copy_struct_from_user() + */ +int copy_struct_from_user(void *dst, size_t ksize, abi_ptr src, size_t usi= ze); + /* Functions for accessing guest memory. The tget and tput functions read/write single values, byteswapping as necessary. The lock_user fun= ction gets a pointer to a contiguous area of guest memory, but does not perfo= rm diff --git a/linux-user/strace.c b/linux-user/strace.c index b4d1098170..42a34e599d 100644 --- a/linux-user/strace.c +++ b/linux-user/strace.c @@ -13,6 +13,9 @@ #include #include #include +#ifdef HAVE_OPENAT2_H +#include +#endif #include #include "qemu.h" #include "user-internals.h" @@ -1063,6 +1066,18 @@ UNUSED static const struct flags open_flags[] =3D { FLAG_END, }; =20 +UNUSED static const struct flags openat2_resolve_flags[] =3D { +#ifdef HAVE_OPENAT2_H + FLAG_GENERIC(RESOLVE_NO_XDEV), + FLAG_GENERIC(RESOLVE_NO_MAGICLINKS), + FLAG_GENERIC(RESOLVE_NO_SYMLINKS), + FLAG_GENERIC(RESOLVE_BENEATH), + FLAG_GENERIC(RESOLVE_IN_ROOT), + FLAG_GENERIC(RESOLVE_CACHED), +#endif + FLAG_END, +}; + UNUSED static const struct flags mount_flags[] =3D { #ifdef MS_BIND FLAG_GENERIC(MS_BIND), @@ -3483,6 +3498,31 @@ print_openat(CPUArchState *cpu_env, const struct sys= callname *name, } #endif =20 +#ifdef TARGET_NR_openat2 +static void +print_openat2(CPUArchState *cpu_env, const struct syscallname *name, + abi_long arg0, abi_long arg1, abi_long arg2, + abi_long arg3, abi_long arg4, abi_long arg5) +{ + struct open_how_ver0 how =3D {0}; + + print_syscall_prologue(name); + print_at_dirfd(arg0, 0); + print_string(arg1, 0); + if (copy_struct_from_user(&how, sizeof(how), arg2, arg3) =3D=3D 0) { + print_open_flags(how.flags, 0); + if (how.flags & TARGET_O_CREAT) { + print_file_mode(how.mode, 0); + } + print_flags(openat2_resolve_flags, how.resolve, 0); + } else { + print_pointer(arg2, 0); + } + print_raw_param(TARGET_ABI_FMT_lu, arg3, 1); + print_syscall_epilogue(name); +} +#endif + #ifdef TARGET_NR_pidfd_send_signal static void print_pidfd_send_signal(CPUArchState *cpu_env, const struct syscallname *n= ame, diff --git a/linux-user/strace.list b/linux-user/strace.list index dfd4237d14..ef658224fc 100644 --- a/linux-user/strace.list +++ b/linux-user/strace.list @@ -715,6 +715,9 @@ #ifdef TARGET_NR_openat { TARGET_NR_openat, "openat" , NULL, print_openat, NULL }, #endif +#ifdef TARGET_NR_openat2 +{ TARGET_NR_openat2, "openat2" , NULL, print_openat2, NULL }, +#endif #ifdef TARGET_NR_osf_adjtime { TARGET_NR_osf_adjtime, "osf_adjtime" , NULL, NULL, NULL }, #endif diff --git a/linux-user/syscall.c b/linux-user/syscall.c index 2febc3bc3f..1354e75694 100644 --- a/linux-user/syscall.c +++ b/linux-user/syscall.c @@ -608,8 +608,7 @@ static int check_zeroed_user(abi_long addr, size_t ksiz= e, size_t usize) * * Similar to kernels uaccess.h:copy_struct_from_user() */ -static int -copy_struct_from_user(void *dst, size_t ksize, abi_ptr src, size_t usize) +int copy_struct_from_user(void *dst, size_t ksize, abi_ptr src, size_t usi= ze) { size_t size =3D MIN(ksize, usize); size_t rest =3D MAX(ksize, usize) - size; @@ -682,11 +681,6 @@ safe_syscall3(ssize_t, write, int, fd, const void *, b= uff, size_t, count) safe_syscall4(int, openat, int, dirfd, const char *, pathname, \ int, flags, mode_t, mode) =20 -struct open_how_ver0 { - __u64 flags; - __u64 mode; - __u64 resolve; -}; safe_syscall4(int, openat2, int, dirfd, const char *, pathname, \ const struct open_how_ver0 *, how, size_t, size) =20 diff --git a/linux-user/syscall_defs.h b/linux-user/syscall_defs.h index de5091c977..0ade83745e 100644 --- a/linux-user/syscall_defs.h +++ b/linux-user/syscall_defs.h @@ -2749,6 +2749,11 @@ struct target_sched_param { }; =20 /* from kernel's include/uapi/linux/openat2.h */ +struct open_how_ver0 { + __u64 flags; + __u64 mode; + __u64 resolve; +}; struct target_open_how_ver0 { abi_ullong flags; abi_ullong mode; diff --git a/meson.build b/meson.build index 10464466ff..77cb5c41d8 100644 --- a/meson.build +++ b/meson.build @@ -2488,6 +2488,7 @@ config_host_data.set('CONFIG_LINUX_MAGIC_H', cc.has_h= eader('linux/magic.h')) config_host_data.set('CONFIG_VALGRIND_H', cc.has_header('valgrind/valgrind= .h')) config_host_data.set('HAVE_BTRFS_H', cc.has_header('linux/btrfs.h')) config_host_data.set('HAVE_DRM_H', cc.has_header('libdrm/drm.h')) +config_host_data.set('HAVE_OPENAT2_H', cc.has_header('linux/openat2.h')) config_host_data.set('HAVE_PTY_H', cc.has_header('pty.h')) config_host_data.set('HAVE_SYS_DISK_H', cc.has_header('sys/disk.h')) config_host_data.set('HAVE_SYS_IOCCOM_H', cc.has_header('sys/ioccom.h')) --=20 2.45.2