From patchwork Mon Jul 1 14:13:36 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Elder X-Patchwork-Id: 1558 Return-Path: Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [IPv6:2001:4b98:dc2:55:216:3eff:fef7:d647]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id 6719F60BF8 for ; Mon, 1 Jul 2019 16:14:08 +0200 (CEST) Received: from emerald.jp (p1871204-ipngn14001hodogaya.kanagawa.ocn.ne.jp [153.220.127.204]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 8797B524; Mon, 1 Jul 2019 16:14:06 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1561990448; bh=6UY9fjbPPQ6nPNlZf6ZDGw/wMiyE0ylE4BSVMmLtvwE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CzIva0SN/UfEsWOaladjfs7yXm9UujlDsZtJG+dfOTpukBUoPbLZvwZn2sRYTSAAk 8aSXEDlgCIIA+WIxO/XlAXO1po+8UbMhLcDI5XafBJ3wxxi+p8qv/qCqMApvNfLsja TloKj9qOLHcvL0osbGWMoWM2kmpIKn5aqAP9QR3o= From: Paul Elder To: libcamera-devel@lists.libcamera.org Date: Mon, 1 Jul 2019 23:13:36 +0900 Message-Id: <20190701141336.10273-2-paul.elder@ideasonboard.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190701141336.10273-1-paul.elder@ideasonboard.com> References: <20190701141336.10273-1-paul.elder@ideasonboard.com> Subject: [libcamera-devel] [PATCH 2/2] libcamera: ipa_module: elfLoadSymbol find symbol regardless of size X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 01 Jul 2019 14:14:08 -0000 Make elfLoadSymbol more generic by making the symbol size an output rather than an input. Also move the memcpy out of elfLoadSymbol. If the size of struct IPAModuleInfo changes between versions, we still want to be able to load it and perhaps do conversions for backwards compatibility. In this case the size should not be a restriction when searching for the symbol. Signed-off-by: Paul Elder Reviewed-by: Laurent Pinchart --- src/libcamera/ipa_module.cpp | 64 ++++++++++++++++++++++-------------- 1 file changed, 40 insertions(+), 24 deletions(-) diff --git a/src/libcamera/ipa_module.cpp b/src/libcamera/ipa_module.cpp index 5a46ec3..d82ac69 100644 --- a/src/libcamera/ipa_module.cpp +++ b/src/libcamera/ipa_module.cpp @@ -17,6 +17,8 @@ #include #include +#include + #include "log.h" #include "pipeline_handler.h" @@ -81,18 +83,27 @@ int elfVerifyIdent(void *map, size_t soSize) return 0; } +/** + * \brief Retrieve address and size of a symbol from an mmap'ed ELF file + * \param[in] map Address of mmap'ed ELF file + * \param[in] soSize Size of mmap'ed ELF file (in bytes) + * \param[in] symbol Symbol name + * + * \return zero or error code, address or nullptr, size of symbol or zero, + * respectively + */ template -int elfLoadSymbol(void *dst, size_t size, void *map, size_t soSize, - const char *symbol) +std::tuple +elfLoadSymbol(void *map, size_t soSize, const char *symbol) { ElfHeader *eHdr = elfPointer(map, 0, soSize); if (!eHdr) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); off_t offset = eHdr->e_shoff + eHdr->e_shentsize * eHdr->e_shstrndx; SecHeader *sHdr = elfPointer(map, offset, soSize); if (!sHdr) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); off_t shnameoff = sHdr->sh_offset; /* Locate .dynsym section header. */ @@ -101,12 +112,12 @@ int elfLoadSymbol(void *dst, size_t size, void *map, size_t soSize, offset = eHdr->e_shoff + eHdr->e_shentsize * i; sHdr = elfPointer(map, offset, soSize); if (!sHdr) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); offset = shnameoff + sHdr->sh_name; char *name = elfPointer(map, offset, soSize); if (!name) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); if (sHdr->sh_type == SHT_DYNSYM && !strcmp(name, ".dynsym")) { dynsym = sHdr; @@ -116,13 +127,13 @@ int elfLoadSymbol(void *dst, size_t size, void *map, size_t soSize, if (dynsym == nullptr) { LOG(IPAModule, Error) << "ELF has no .dynsym section"; - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); } offset = eHdr->e_shoff + eHdr->e_shentsize * dynsym->sh_link; sHdr = elfPointer(map, offset, soSize); if (!sHdr) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); off_t dynsym_nameoff = sHdr->sh_offset; /* Locate symbol in the .dynsym section. */ @@ -132,16 +143,16 @@ int elfLoadSymbol(void *dst, size_t size, void *map, size_t soSize, offset = dynsym->sh_offset + dynsym->sh_entsize * i; SymHeader *sym = elfPointer(map, offset, soSize); if (!sym) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); offset = dynsym_nameoff + sym->st_name; char *name = elfPointer(map, offset, soSize, strlen(symbol) + 1); if (!name) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); if (!strcmp(name, symbol) && - sym->st_info & STB_GLOBAL && sym->st_size == size) { + sym->st_info & STB_GLOBAL) { targetSymbol = sym; break; } @@ -149,24 +160,22 @@ int elfLoadSymbol(void *dst, size_t size, void *map, size_t soSize, if (targetSymbol == nullptr) { LOG(IPAModule, Error) << "Symbol " << symbol << " not found"; - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); } /* Locate and return data of symbol. */ if (targetSymbol->st_shndx >= eHdr->e_shnum) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); offset = eHdr->e_shoff + targetSymbol->st_shndx * eHdr->e_shentsize; sHdr = elfPointer(map, offset, soSize); if (!sHdr) - return -ENOEXEC; + return std::make_tuple(-ENOEXEC, nullptr, 0); offset = sHdr->sh_offset + (targetSymbol->st_value - sHdr->sh_addr); - char *data = elfPointer(map, offset, soSize, size); + char *data = elfPointer(map, offset, soSize, targetSymbol->st_size); if (!data) - return -ENOEXEC; - - memcpy(dst, data, size); + return std::make_tuple(-ENOEXEC, nullptr, 0); - return 0; + return std::make_tuple(0, data, targetSymbol->st_size); } } /* namespace */ @@ -257,8 +266,10 @@ int IPAModule::loadIPAModuleInfo() return ret; } - size_t soSize; + void *data; + size_t dataSize; void *map; + size_t soSize; struct stat st; int ret = fstat(fd, &st); if (ret < 0) @@ -275,11 +286,16 @@ int IPAModule::loadIPAModuleInfo() goto unmap; if (sizeof(unsigned long) == 4) - ret = elfLoadSymbol - (&info_, sizeof(info_), map, soSize, "ipaModuleInfo"); + std::tie(ret, data, dataSize) = + elfLoadSymbol + (map, soSize, "ipaModuleInfo"); else - ret = elfLoadSymbol - (&info_, sizeof(info_), map, soSize, "ipaModuleInfo"); + std::tie(ret, data, dataSize) = + elfLoadSymbol + (map, soSize, "ipaModuleInfo"); + + if (!ret && dataSize == sizeof(info_)) + memcpy(&info_, data, dataSize); if (info_.moduleAPIVersion != IPA_MODULE_API_VERSION) { LOG(IPAModule, Error) << "IPA module API version mismatch";