From e2e3610e6e76b782b77e79581a26f4c2fb619d9d Mon Sep 17 00:00:00 2001 From: Jeff Sharkey Date: Mon, 8 Jan 2018 11:43:46 -0700 Subject: [PATCH] Add "default_normal" support for sdcardfs. Also cleans up fallback-retry logic for older kernels by progressively removing each newer flag with each retry. Test: internal CTS Bug: 64672411 Change-Id: I3de3b64b68838fb2ef4505fe73c4e9865b2f9026 --- sdcard/sdcard.cpp | 54 +++++++++++++++++++++++++---------------------- 1 file changed, 29 insertions(+), 25 deletions(-) diff --git a/sdcard/sdcard.cpp b/sdcard/sdcard.cpp index 77d5a91f1..0d5e5aff6 100644 --- a/sdcard/sdcard.cpp +++ b/sdcard/sdcard.cpp @@ -321,30 +321,26 @@ static void run(const char* source_path, const char* label, uid_t uid, static bool sdcardfs_setup(const std::string& source_path, const std::string& dest_path, uid_t fsuid, gid_t fsgid, bool multi_user, userid_t userid, gid_t gid, - mode_t mask, bool derive_gid) { - std::string opts = android::base::StringPrintf( - "fsuid=%d,fsgid=%d,%s%smask=%d,userid=%d,gid=%d", fsuid, fsgid, - multi_user ? "multiuser," : "", derive_gid ? "derive_gid," : "", mask, userid, gid); + mode_t mask, bool derive_gid, bool default_normal) { + // Try several attempts, each time with one less option, to gracefully + // handle older kernels that aren't updated yet. + for (int i = 0; i < 4; i++) { + std::string new_opts; + if (multi_user && i < 3) new_opts += "multiuser,"; + if (derive_gid && i < 2) new_opts += "derive_gid,"; + if (default_normal && i < 1) new_opts += "default_normal,"; - if (mount(source_path.c_str(), dest_path.c_str(), "sdcardfs", - MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts.c_str()) == -1) { - if (derive_gid) { - PLOG(ERROR) << "trying to mount sdcardfs filesystem without derive_gid"; - /* Maybe this isn't supported on this kernel. Try without. */ - opts = android::base::StringPrintf("fsuid=%d,fsgid=%d,%smask=%d,userid=%d,gid=%d", - fsuid, fsgid, multi_user ? "multiuser," : "", mask, - userid, gid); - if (mount(source_path.c_str(), dest_path.c_str(), "sdcardfs", - MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts.c_str()) == -1) { - PLOG(ERROR) << "failed to mount sdcardfs filesystem"; - return false; - } + auto opts = android::base::StringPrintf("fsuid=%d,fsgid=%d,%smask=%d,userid=%d,gid=%d", + fsuid, fsgid, new_opts.c_str(), mask, userid, gid); + if (mount(source_path.c_str(), dest_path.c_str(), "sdcardfs", + MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts.c_str()) == -1) { + PLOG(WARNING) << "Failed to mount sdcardfs with options " << opts; } else { - PLOG(ERROR) << "failed to mount sdcardfs filesystem"; - return false; + return true; } } - return true; + + return false; } static bool sdcardfs_setup_bind_remount(const std::string& source_path, const std::string& dest_path, @@ -370,7 +366,7 @@ static bool sdcardfs_setup_bind_remount(const std::string& source_path, const st static void run_sdcardfs(const std::string& source_path, const std::string& label, uid_t uid, gid_t gid, userid_t userid, bool multi_user, bool full_write, - bool derive_gid) { + bool derive_gid, bool default_normal) { std::string dest_path_default = "/mnt/runtime/default/" + label; std::string dest_path_read = "/mnt/runtime/read/" + label; std::string dest_path_write = "/mnt/runtime/write/" + label; @@ -380,7 +376,7 @@ static void run_sdcardfs(const std::string& source_path, const std::string& labe // Multi-user storage is fully isolated per user, so "other" // permissions are completely masked off. if (!sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid, - AID_SDCARD_RW, 0006, derive_gid) || + AID_SDCARD_RW, 0006, derive_gid, default_normal) || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read, AID_EVERYBODY, 0027) || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write, AID_EVERYBODY, full_write ? 0007 : 0027)) { @@ -391,7 +387,7 @@ static void run_sdcardfs(const std::string& source_path, const std::string& labe // the Android directories are masked off to a single user // deep inside attr_from_stat(). if (!sdcardfs_setup(source_path, dest_path_default, uid, gid, multi_user, userid, - AID_SDCARD_RW, 0006, derive_gid) || + AID_SDCARD_RW, 0006, derive_gid, default_normal) || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_read, AID_EVERYBODY, full_write ? 0027 : 0022) || !sdcardfs_setup_bind_remount(dest_path_default, dest_path_write, AID_EVERYBODY, @@ -466,12 +462,16 @@ int main(int argc, char **argv) { bool multi_user = false; bool full_write = false; bool derive_gid = false; + bool default_normal = false; int i; struct rlimit rlim; int fs_version; + setenv("ANDROID_LOG_TAGS", "*:v", 1); + android::base::InitLogging(argv, android::base::LogdLogger(android::base::SYSTEM)); + int opt; - while ((opt = getopt(argc, argv, "u:g:U:mwG")) != -1) { + while ((opt = getopt(argc, argv, "u:g:U:mwGi")) != -1) { switch (opt) { case 'u': uid = strtoul(optarg, NULL, 10); @@ -491,6 +491,9 @@ int main(int argc, char **argv) { case 'G': derive_gid = true; break; + case 'i': + default_normal = true; + break; case '?': default: return usage(); @@ -534,7 +537,8 @@ int main(int argc, char **argv) { } if (should_use_sdcardfs()) { - run_sdcardfs(source_path, label, uid, gid, userid, multi_user, full_write, derive_gid); + run_sdcardfs(source_path, label, uid, gid, userid, multi_user, full_write, derive_gid, + default_normal); } else { run(source_path, label, uid, gid, userid, multi_user, full_write); }