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Commit 7f759d6

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Merge commit 'd9ab3cb7bf033397c02b4bfd62a59c69b5ef8f82' into internal-merge-3.1-2022-11-08-1046
2 parents fa19407 + d9ab3cb commit 7f759d6

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3 files changed

+41
-18
lines changed

3 files changed

+41
-18
lines changed

‎src/pal/src/include/pal/sharedmemory.h‎

Lines changed: 3 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -92,6 +92,7 @@ class SharedMemoryException
9292
class SharedMemoryHelpers
9393
{
9494
private:
95+
static const mode_t PermissionsMask_CurrentUser_ReadWrite;
9596
static const mode_t PermissionsMask_CurrentUser_ReadWriteExecute;
9697
static const mode_t PermissionsMask_AllUsers_ReadWrite;
9798
static const mode_t PermissionsMask_AllUsers_ReadWriteExecute;
@@ -110,12 +111,12 @@ class SharedMemoryHelpers
110111
static void BuildSharedFilesPath(PathCharString& destination, const char *suffix, int suffixByteCount);
111112
static bool AppendUInt32String(PathCharString& destination, UINT32 value);
112113

113-
static bool EnsureDirectoryExists(const char *path, bool isGlobalLockAcquired, bool createIfNotExist = true, bool isSystemDirectory = false);
114+
static bool EnsureDirectoryExists(const char *path, bool isGlobalLockAcquired, bool hasCurrentUserAccessOnly, bool setStickyFlag, bool createIfNotExist = true, bool isSystemDirectory = false);
114115
private:
115116
static int Open(LPCSTR path, int flags, mode_t mode = static_cast<mode_t>(0));
116117
public:
117118
static int OpenDirectory(LPCSTR path);
118-
static int CreateOrOpenFile(LPCSTR path, bool createIfNotExist = true, bool *createdRef = nullptr);
119+
static int CreateOrOpenFile(LPCSTR path, bool createIfNotExist = true, bool isSessionScope = true, bool *createdRef = nullptr);
119120
static void CloseFile(int fileDescriptor);
120121

121122
static SIZE_T GetFileSize(int fileDescriptor);

‎src/pal/src/sharedmemory/sharedmemory.cpp‎

Lines changed: 35 additions & 13 deletions
Original file line numberDiff line numberDiff line change
@@ -63,6 +63,7 @@ DWORD SharedMemoryException::GetErrorCode() const
6363
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
6464
// SharedMemoryHelpers
6565

66+
const mode_t SharedMemoryHelpers::PermissionsMask_CurrentUser_ReadWrite = S_IRUSR | S_IWUSR;
6667
const mode_t SharedMemoryHelpers::PermissionsMask_CurrentUser_ReadWriteExecute = S_IRUSR | S_IWUSR | S_IXUSR;
6768
const mode_t SharedMemoryHelpers::PermissionsMask_AllUsers_ReadWrite =
6869
S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH;
@@ -97,13 +98,22 @@ SIZE_T SharedMemoryHelpers::AlignUp(SIZE_T value, SIZE_T alignment)
9798
bool SharedMemoryHelpers::EnsureDirectoryExists(
9899
const char *path,
99100
bool isGlobalLockAcquired,
101+
bool hasCurrentUserAccessOnly,
102+
bool setStickyFlag,
100103
bool createIfNotExist,
101104
bool isSystemDirectory)
102105
{
103106
_ASSERTE(path != nullptr);
104107
_ASSERTE(!(isSystemDirectory && createIfNotExist)); // should not create or change permissions on system directories
105108
_ASSERTE(SharedMemoryManager::IsCreationDeletionProcessLockAcquired());
106109
_ASSERTE(!isGlobalLockAcquired || SharedMemoryManager::IsCreationDeletionFileLockAcquired());
110+
_ASSERTE(!(setStickyFlag && hasCurrentUserAccessOnly)); // Sticky bit doesn't make sense with current user access only
111+
112+
mode_t mode = hasCurrentUserAccessOnly ? PermissionsMask_CurrentUser_ReadWriteExecute : PermissionsMask_AllUsers_ReadWriteExecute;
113+
if (setStickyFlag)
114+
{
115+
mode |= S_ISVTX;
116+
}
107117

108118
// Check if the path already exists
109119
struct stat statInfo;
@@ -124,11 +134,11 @@ bool SharedMemoryHelpers::EnsureDirectoryExists(
124134

125135
if (isGlobalLockAcquired)
126136
{
127-
if (mkdir(path, PermissionsMask_AllUsers_ReadWriteExecute) != 0)
137+
if (mkdir(path, mode) != 0)
128138
{
129139
throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
130140
}
131-
if (chmod(path, PermissionsMask_AllUsers_ReadWriteExecute) != 0)
141+
if (chmod(path, mode) != 0)
132142
{
133143
rmdir(path);
134144
throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
@@ -143,7 +153,7 @@ bool SharedMemoryHelpers::EnsureDirectoryExists(
143153
{
144154
throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
145155
}
146-
if (chmod(tempPath, PermissionsMask_AllUsers_ReadWriteExecute) != 0)
156+
if (chmod(tempPath, mode) != 0)
147157
{
148158
rmdir(tempPath);
149159
throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
@@ -183,13 +193,18 @@ bool SharedMemoryHelpers::EnsureDirectoryExists(
183193
// For non-system directories (such as gSharedFilesPath/SHARED_MEMORY_RUNTIME_TEMP_DIRECTORY_NAME),
184194
// require sufficient permissions for all users and try to update them if requested to create the directory, so that
185195
// shared memory files may be shared by all processes on the system.
186-
if ((statInfo.st_mode & PermissionsMask_AllUsers_ReadWriteExecute) == PermissionsMask_AllUsers_ReadWriteExecute)
196+
if ((statInfo.st_mode & mode) == mode)
187197
{
188198
return true;
189199
}
190-
if (!createIfNotExist || chmod(path, PermissionsMask_AllUsers_ReadWriteExecute) != 0)
200+
if (!createIfNotExist || chmod(path, mode) != 0)
191201
{
192-
throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
202+
// We were not asked to create the path or we weren't able to set the new permissions.
203+
// As a last resort, check that at least the current user has full access.
204+
if ((statInfo.st_mode & PermissionsMask_CurrentUser_ReadWriteExecute) != PermissionsMask_CurrentUser_ReadWriteExecute)
205+
{
206+
throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
207+
}
193208
}
194209
return true;
195210
}
@@ -239,7 +254,7 @@ int SharedMemoryHelpers::OpenDirectory(LPCSTR path)
239254
return fileDescriptor;
240255
}
241256

242-
int SharedMemoryHelpers::CreateOrOpenFile(LPCSTR path, bool createIfNotExist, bool *createdRef)
257+
int SharedMemoryHelpers::CreateOrOpenFile(LPCSTR path, bool createIfNotExist, bool isSessionScope, bool *createdRef)
243258
{
244259
_ASSERTE(path != nullptr);
245260
_ASSERTE(path[0] != '\0');
@@ -269,12 +284,13 @@ int SharedMemoryHelpers::CreateOrOpenFile(LPCSTR path, bool createIfNotExist, bo
269284

270285
// File does not exist, create the file
271286
openFlags |= O_CREAT | O_EXCL;
272-
fileDescriptor = Open(path, openFlags, PermissionsMask_AllUsers_ReadWrite);
287+
mode_t mode = isSessionScope ? PermissionsMask_CurrentUser_ReadWrite : PermissionsMask_AllUsers_ReadWrite;
288+
fileDescriptor = Open(path, openFlags, mode);
273289
_ASSERTE(fileDescriptor != -1);
274290

275291
// The permissions mask passed to open() is filtered by the process' permissions umask, so open() may not set all of
276292
// the requested permissions. Use chmod() to set the proper permissions.
277-
if (chmod(path, PermissionsMask_AllUsers_ReadWrite) != 0)
293+
if (chmod(path, mode) != 0)
278294
{
279295
CloseFile(fileDescriptor);
280296
unlink(path);
@@ -655,7 +671,7 @@ SharedMemoryProcessDataHeader *SharedMemoryProcessDataHeader::CreateOrOpen(
655671
SharedMemoryHelpers::VerifyStringOperation(SharedMemoryManager::CopySharedMemoryBasePath(filePath));
656672
SharedMemoryHelpers::VerifyStringOperation(filePath.Append('/'));
657673
SharedMemoryHelpers::VerifyStringOperation(id.AppendSessionDirectoryName(filePath));
658-
if (!SharedMemoryHelpers::EnsureDirectoryExists(filePath, true /* isGlobalLockAcquired */, createIfNotExist))
674+
if (!SharedMemoryHelpers::EnsureDirectoryExists(filePath, true /* isGlobalLockAcquired */, id.IsSessionScope(), false /* setStickyFlag */, createIfNotExist))
659675
{
660676
_ASSERTE(!createIfNotExist);
661677
return nullptr;
@@ -668,7 +684,7 @@ SharedMemoryProcessDataHeader *SharedMemoryProcessDataHeader::CreateOrOpen(
668684
SharedMemoryHelpers::VerifyStringOperation(filePath.Append(id.GetName(), id.GetNameCharCount()));
669685

670686
bool createdFile;
671-
int fileDescriptor = SharedMemoryHelpers::CreateOrOpenFile(filePath, createIfNotExist, &createdFile);
687+
int fileDescriptor = SharedMemoryHelpers::CreateOrOpenFile(filePath, createIfNotExist, id.IsSessionScope(), &createdFile);
672688
if (fileDescriptor == -1)
673689
{
674690
_ASSERTE(!createIfNotExist);
@@ -1117,17 +1133,23 @@ void SharedMemoryManager::AcquireCreationDeletionFileLock()
11171133
if (!SharedMemoryHelpers::EnsureDirectoryExists(
11181134
*gSharedFilesPath,
11191135
false /* isGlobalLockAcquired */,
1136+
false /* hasCurrentUserAccessOnly */,
1137+
true /* setStickyFlag */,
11201138
false /* createIfNotExist */,
11211139
true /* isSystemDirectory */))
11221140
{
11231141
throw SharedMemoryException(static_cast<DWORD>(SharedMemoryError::IO));
11241142
}
11251143
SharedMemoryHelpers::EnsureDirectoryExists(
11261144
*s_runtimeTempDirectoryPath,
1127-
false /* isGlobalLockAcquired */);
1145+
false /* isGlobalLockAcquired */,
1146+
false /* hasCurrentUserAccessOnly */,
1147+
true /* setStickyFlag */);
11281148
SharedMemoryHelpers::EnsureDirectoryExists(
11291149
*s_sharedMemoryDirectoryPath,
1130-
false /* isGlobalLockAcquired */);
1150+
false /* isGlobalLockAcquired */,
1151+
false /* hasCurrentUserAccessOnly */,
1152+
true /* setStickyFlag */);
11311153
s_creationDeletionLockFileDescriptor = SharedMemoryHelpers::OpenDirectory(*s_sharedMemoryDirectoryPath);
11321154
if (s_creationDeletionLockFileDescriptor == -1)
11331155
{

‎src/pal/src/synchobj/mutex.cpp‎

Lines changed: 3 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1186,7 +1186,7 @@ SharedMemoryProcessDataHeader *NamedMutexProcessData::CreateOrOpen(
11861186
SharedMemoryHelpers::BuildSharedFilesPath(lockFilePath, SHARED_MEMORY_LOCK_FILES_DIRECTORY_NAME);
11871187
if (created)
11881188
{
1189-
SharedMemoryHelpers::EnsureDirectoryExists(lockFilePath, true /* isGlobalLockAcquired */);
1189+
SharedMemoryHelpers::EnsureDirectoryExists(lockFilePath, true /* isGlobalLockAcquired */, false /* hasCurrentUserAccessOnly */, true /* setStickyFlag */);
11901190
}
11911191

11921192
// Create the session directory
@@ -1195,15 +1195,15 @@ SharedMemoryProcessDataHeader *NamedMutexProcessData::CreateOrOpen(
11951195
SharedMemoryHelpers::VerifyStringOperation(id->AppendSessionDirectoryName(lockFilePath));
11961196
if (created)
11971197
{
1198-
SharedMemoryHelpers::EnsureDirectoryExists(lockFilePath, true /* isGlobalLockAcquired */);
1198+
SharedMemoryHelpers::EnsureDirectoryExists(lockFilePath, true /* isGlobalLockAcquired */, id->IsSessionScope(), false /* setStickyFlag */);
11991199
autoCleanup.m_lockFilePath = &lockFilePath;
12001200
autoCleanup.m_sessionDirectoryPathCharCount = lockFilePath.GetCount();
12011201
}
12021202

12031203
// Create or open the lock file
12041204
SharedMemoryHelpers::VerifyStringOperation(lockFilePath.Append('/'));
12051205
SharedMemoryHelpers::VerifyStringOperation(lockFilePath.Append(id->GetName(), id->GetNameCharCount()));
1206-
int lockFileDescriptor = SharedMemoryHelpers::CreateOrOpenFile(lockFilePath, created);
1206+
int lockFileDescriptor = SharedMemoryHelpers::CreateOrOpenFile(lockFilePath, created, id->IsSessionScope());
12071207
if (lockFileDescriptor == -1)
12081208
{
12091209
_ASSERTE(!created);

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