From patchwork Wed Jun 17 09:05:18 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Paul Elder X-Patchwork-Id: 4071 Return-Path: Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 099D1603BF for ; Wed, 17 Jun 2020 11:05:33 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="V+i2HrsC"; dkim-atps=neutral Received: from jade.flets-east.jp (unknown [IPv6:2400:4051:61:600:4409:e6df:9984:3512]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 62EEDF9; Wed, 17 Jun 2020 11:05:31 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1592384732; bh=hHGYiu6s81bXhCuH0d9KCgdN39W9g7tiLgGYiQnTPVM=; h=From:To:Cc:Subject:Date:From; b=V+i2HrsCm5bvmGhyaB2pV+T3ue91qmmRJwn6jJfDO8kNy09YUt3tQWuiNzhIMf9k/ 3v9SmFhilnOovUB8F4m2j9FfKjTyr21T9j3U1ci9mJdhsvb0xy50iz2ryxEJKlUwLh QlSm/w0z2mdQydcuEZn2l7uxXAXSV3EdK8fnQwyc= From: Paul Elder To: libcamera-devel@lists.libcamera.org Date: Wed, 17 Jun 2020 18:05:18 +0900 Message-Id: <20200617090518.40244-1-paul.elder@ideasonboard.com> X-Mailer: git-send-email 2.27.0 MIME-Version: 1.0 Subject: [libcamera-devel] [PATCH v2] v4l2: v4l2_compat: Intercept open64, openat64, and mmap64 X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Jun 2020 09:05:33 -0000 Some applications (eg. Firefox, Google Chrome, Skype) use open64, openat64, and mmap64 instead of their non-64 versions that we currently intercept. Intercept these calls as well. _LARGEFILE64_SOURCE needs to be set so that the 64-bit symbols are available and not synonymous to the non-64-bit versions on 64-bit systems. Also, since we set _FILE_OFFSET_BITS to 32 to force the various open and mmap symbols that we export to not be the 64-bit versions, our dlsym to get the original open and mmap calls will not automatically be converted to their 64-bit versions. Since we intercept both 32-bit and 64-bit versions of open and mmap, we should be using the 64-bit version to service both. Fetch the 64-bit versions of openat and mmap directly. musl defines the 64-bit symbols as macros that are equivalent to the non-64-bit symbols, so we put compile guards that check if the 64-bit symbols are defined. Signed-off-by: Paul Elder Reviewed-by: Niklas Söderlund Tested-by: Laurent Pinchart # Compile with musl Reviewed-by: Laurent Pinchart --- Changes in v2: - squash intercept 64-bit calls and use 64-bit calls into this one patch - use off64_t instead of __off64_t - add compile guard to get musl to play nicely with the 64-bit calls coexisting with the non-64-bit calls --- src/v4l2/meson.build | 1 + src/v4l2/v4l2_camera_proxy.cpp | 2 +- src/v4l2/v4l2_camera_proxy.h | 3 ++- src/v4l2/v4l2_compat.cpp | 33 ++++++++++++++++++++++++++++++++ src/v4l2/v4l2_compat_manager.cpp | 6 +++--- src/v4l2/v4l2_compat_manager.h | 5 +++-- 6 files changed, 43 insertions(+), 7 deletions(-) diff --git a/src/v4l2/meson.build b/src/v4l2/meson.build index 0fb941e..f2e4aaf 100644 --- a/src/v4l2/meson.build +++ b/src/v4l2/meson.build @@ -15,6 +15,7 @@ v4l2_compat_cpp_args = [ # file operations, disable transparent large file support. '-U_FILE_OFFSET_BITS', '-D_FILE_OFFSET_BITS=32', + '-D_LARGEFILE64_SOURCE', '-fvisibility=hidden', ] diff --git a/src/v4l2/v4l2_camera_proxy.cpp b/src/v4l2/v4l2_camera_proxy.cpp index d7f14e6..7425029 100644 --- a/src/v4l2/v4l2_camera_proxy.cpp +++ b/src/v4l2/v4l2_camera_proxy.cpp @@ -75,7 +75,7 @@ void V4L2CameraProxy::close() } void *V4L2CameraProxy::mmap(void *addr, size_t length, int prot, int flags, - off_t offset) + off64_t offset) { LOG(V4L2Compat, Debug) << "Servicing mmap"; diff --git a/src/v4l2/v4l2_camera_proxy.h b/src/v4l2/v4l2_camera_proxy.h index 7c65c88..27d3e50 100644 --- a/src/v4l2/v4l2_camera_proxy.h +++ b/src/v4l2/v4l2_camera_proxy.h @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -28,7 +29,7 @@ public: int open(bool nonBlocking); void dup(); void close(); - void *mmap(void *addr, size_t length, int prot, int flags, off_t offset); + void *mmap(void *addr, size_t length, int prot, int flags, off64_t offset); int munmap(void *addr, size_t length); int ioctl(unsigned long request, void *arg); diff --git a/src/v4l2/v4l2_compat.cpp b/src/v4l2/v4l2_compat.cpp index 2a9a176..7d45ffe 100644 --- a/src/v4l2/v4l2_compat.cpp +++ b/src/v4l2/v4l2_compat.cpp @@ -38,6 +38,18 @@ LIBCAMERA_PUBLIC int open(const char *path, int oflag, ...) oflag, mode); } +#ifndef open64 +LIBCAMERA_PUBLIC int open64(const char *path, int oflag, ...) +{ + mode_t mode = 0; + if (oflag & O_CREAT || oflag & O_TMPFILE) + extract_va_arg(mode_t, mode, oflag); + + return V4L2CompatManager::instance()->openat(AT_FDCWD, path, + oflag | O_LARGEFILE, mode); +} +#endif + /* _FORTIFY_SOURCE redirects open to __open_2 */ LIBCAMERA_PUBLIC int __open_2(const char *path, int oflag) { @@ -53,6 +65,18 @@ LIBCAMERA_PUBLIC int openat(int dirfd, const char *path, int oflag, ...) return V4L2CompatManager::instance()->openat(dirfd, path, oflag, mode); } +#ifndef openat64 +LIBCAMERA_PUBLIC int openat64(int dirfd, const char *path, int oflag, ...) +{ + mode_t mode = 0; + if (oflag & O_CREAT || oflag & O_TMPFILE) + extract_va_arg(mode_t, mode, oflag); + + return V4L2CompatManager::instance()->openat(dirfd, path, + oflag | O_LARGEFILE, mode); +} +#endif + LIBCAMERA_PUBLIC int __openat_2(int dirfd, const char *path, int oflag) { return openat(dirfd, path, oflag); @@ -75,6 +99,15 @@ LIBCAMERA_PUBLIC void *mmap(void *addr, size_t length, int prot, int flags, fd, offset); } +#ifndef mmap64 +LIBCAMERA_PUBLIC void *mmap64(void *addr, size_t length, int prot, int flags, + int fd, off64_t offset) +{ + return V4L2CompatManager::instance()->mmap(addr, length, prot, flags, + fd, offset); +} +#endif + LIBCAMERA_PUBLIC int munmap(void *addr, size_t length) { return V4L2CompatManager::instance()->munmap(addr, length); diff --git a/src/v4l2/v4l2_compat_manager.cpp b/src/v4l2/v4l2_compat_manager.cpp index 56533c4..8da3316 100644 --- a/src/v4l2/v4l2_compat_manager.cpp +++ b/src/v4l2/v4l2_compat_manager.cpp @@ -39,11 +39,11 @@ void get_symbol(T &func, const char *name) V4L2CompatManager::V4L2CompatManager() : cm_(nullptr) { - get_symbol(fops_.openat, "openat"); + get_symbol(fops_.openat, "openat64"); get_symbol(fops_.dup, "dup"); get_symbol(fops_.close, "close"); get_symbol(fops_.ioctl, "ioctl"); - get_symbol(fops_.mmap, "mmap"); + get_symbol(fops_.mmap, "mmap64"); get_symbol(fops_.munmap, "munmap"); } @@ -200,7 +200,7 @@ int V4L2CompatManager::close(int fd) } void *V4L2CompatManager::mmap(void *addr, size_t length, int prot, int flags, - int fd, off_t offset) + int fd, off64_t offset) { V4L2CameraProxy *proxy = getProxy(fd); if (!proxy) diff --git a/src/v4l2/v4l2_compat_manager.h b/src/v4l2/v4l2_compat_manager.h index 14338a5..3d4e512 100644 --- a/src/v4l2/v4l2_compat_manager.h +++ b/src/v4l2/v4l2_compat_manager.h @@ -11,6 +11,7 @@ #include #include #include +#include #include #include @@ -30,7 +31,7 @@ public: using close_func_t = int (*)(int fd); using ioctl_func_t = int (*)(int fd, unsigned long request, ...); using mmap_func_t = void *(*)(void *addr, size_t length, int prot, - int flags, int fd, off_t offset); + int flags, int fd, off64_t offset); using munmap_func_t = int (*)(void *addr, size_t length); openat_func_t openat; @@ -51,7 +52,7 @@ public: int dup(int oldfd); int close(int fd); void *mmap(void *addr, size_t length, int prot, int flags, - int fd, off_t offset); + int fd, off64_t offset); int munmap(void *addr, size_t length); int ioctl(int fd, unsigned long request, void *arg);