nextcloud · hamza221 · Aug 21, 2026
@@ -625,12 +625,23 @@ public function createShare(IShare $share): IShare {
 				$share->setTarget($target);
 			}
 		} catch (AlreadySharedException $e) {
+			$existingShare = $e->getExistingShare();
+
+			/*
+			 * Reusing a share which is hidden because one of the accounts involved
+			 * in it is disabled would leave the recipient without access, so report
+			 * it to the sharer instead. Such a share has to be deleted first.
+			 */
+			if ($this->isHiddenDisabledUserShare($existingShare)) {
+				throw $e;
+			}
+
 			// If a share for the same target already exists, dont create a new one,
 			// but do trigger the hooks and notifications again
 			$oldShare = $share;
 
 			// Reuse the node we already have
-			$share = $e->getExistingShare();
+			$share = $existingShare;
 			$share->setNode($oldShare->getNode());
 		}
 
@@ -1151,7 +1162,7 @@ public function getSharesBy(string $userId, int $shareType, ?Node $path = null,
 			return [];
 		}
 
-		if ($onlyValid && $this->config->getAppValue('files_sharing', 'hide_disabled_user_shares', 'no') === 'yes') {
+		if ($onlyValid && $this->config->getAppValue('files_sharing', 'hide_disabled_user_shares', 'yes') === 'yes') {
 			/*
 			 * If shares from disabled users are hidden, check user status first to avoid useless work.
 			 * Otherwise all shares would’ve been filtered out by checkShare anyway.
@@ -1181,7 +1192,7 @@ public function getSharesBy(string $userId, int $shareType, ?Node $path = null,
 				$added++;
 				if ($onlyValid) {
 					try {
-						$this->checkShare($share, $added);
+						$this->checkShare($share, $added, $userId);
 					} catch (ShareNotFound $e) {
 						// Ignore since this basically means the share is deleted
 						continue;
@@ -1243,7 +1254,7 @@ public function getSharedWith(string $userId, int $shareType, ?Node $node = null
 		// remove all shares which are already expired
 		foreach ($shares as $key => $share) {
 			try {
-				$this->checkShare($share);
+				$this->checkShare($share, viewer: $userId);
 			} catch (ShareNotFound $e) {
 				unset($shares[$key]);
 			}
@@ -1282,10 +1293,10 @@ public function getSharedWithByPath(string $userId, int $shareType, string $path
 			$shares = new \IteratorIterator($shares);
 		}
 
-		return new \CallbackFilterIterator($shares, function (IShare $share) {
+		return new \CallbackFilterIterator($shares, function (IShare $share) use ($userId) {
 			// remove all shares which are already expired
 			try {
-				$this->checkShare($share);
+				$this->checkShare($share, viewer: $userId);
 				return true;
 			} catch (ShareNotFound $e) {
 				return false;
@@ -1319,7 +1330,7 @@ public function getShareById($id, $recipient = null, bool $onlyValid = true): IS
 		$share = $provider->getShareById($id, $recipient);
 
 		if ($onlyValid) {
-			$this->checkShare($share);
+			$this->checkShare($share, viewer: $recipient);
 		}
 
 		return $share;
@@ -1403,27 +1414,51 @@ public function getShareByToken(string $token): IShare {
 		return $share;
 	}
 
+	/**
+	 * Whether a share has to be hidden because one of the accounts involved in it
+	 * is disabled.
+	 *
+	 * A share initiated by an account that got disabled stays visible to the owner
+	 * of the shared item, so that they can still manage or delete it.
+	 *
+	 * @param ?string $viewer Account the share is checked for, if known
+	 */
+	private function isHiddenDisabledUserShare(IShare $share, ?string $viewer = null): bool {
+		if ($this->config->getAppValue('files_sharing', 'hide_disabled_user_shares', 'yes') !== 'yes') {
+			return false;
+		}
+
+		$uids = [$share->getShareOwner()];
+		if ($viewer !== $share->getShareOwner()) {
+			$uids[] = $share->getSharedBy();
+		}
+
+		foreach (array_unique($uids) as $uid) {
+			$user = $this->userManager->get($uid);
+			if ($user?->isEnabled() === false) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
 	/**
 	 * Check expire date and disabled owner
 	 *
 	 * @param int &$added If given, will be decremented if the share is deleted
+	 * @param ?string $viewer Account the share is checked for, defaults to the account of the current session
 	 * @throws ShareNotFound
 	 */
-	private function checkShare(IShare $share, int &$added = 1): void {
+	private function checkShare(IShare $share, int &$added = 1, ?string $viewer = null): void {
 		if ($share->isExpired()) {
 			$this->deleteShare($share);
 			// Remove 1 to added, because this share was deleted
 			$added--;
 			throw new ShareNotFound($this->l->t('The requested share does not exist anymore'));
 		}
-		if ($this->config->getAppValue('files_sharing', 'hide_disabled_user_shares', 'yes') === 'yes') {
-			$uids = array_unique([$share->getShareOwner(), $share->getSharedBy()]);
-			foreach ($uids as $uid) {
-				$user = $this->userManager->get($uid);
-				if ($user?->isEnabled() === false) {
-					throw new ShareNotFound($this->l->t('The requested share does not exist anymore'));
-				}
-			}
+		if ($this->isHiddenDisabledUserShare($share, $viewer ?? $this->userSession->getUser()?->getUID())) {
+			throw new ShareNotFound($this->l->t('The requested share does not exist anymore'));
 		}
 
 		// For link and email shares, verify the share owner can still create such shares

@@ -813,6 +813,61 @@ public function testGetShareById(): void {
 		$this->assertEquals($share, $this->manager->getShareById('default:42'));
 	}
 
+	public function testGetShareByIdOfDisabledInitiatorAsShareOwner(): void {
+		$this->config->method('getAppValue')
+			->willReturnMap([
+				['files_sharing', 'hide_disabled_user_shares', 'yes', 'yes'],
+			]);
+
+		$share = $this->manager->newShare();
+		$share->setShareType(IShare::TYPE_USER)
+			->setShareOwner('owner')
+			->setSharedBy('initiator')
+			->setSharedWith('recipient');
+
+		$this->userManager->method('get')->willReturnMap([
+			['owner', $this->createEnabledUser(true)],
+			['initiator', $this->createEnabledUser(false)],
+		]);
+
+		$this->defaultProvider
+			->expects($this->once())
+			->method('getShareById')
+			->with('42', 'owner')
+			->willReturn($share);
+
+		$this->assertSame($share, $this->manager->getShareById('default:42', 'owner'));
+	}
+
+	public function testGetShareByIdOfDisabledInitiatorAsOtherUser(): void {
+		$this->expectException(ShareNotFound::class);
+		$this->expectExceptionMessage('The requested share does not exist anymore');
+
+		$this->config->method('getAppValue')
+			->willReturnMap([
+				['files_sharing', 'hide_disabled_user_shares', 'yes', 'yes'],
+			]);
+
+		$share = $this->manager->newShare();
+		$share->setShareType(IShare::TYPE_USER)
+			->setShareOwner('owner')
+			->setSharedBy('initiator')
+			->setSharedWith('recipient');
+
+		$this->userManager->method('get')->willReturnMap([
+			['owner', $this->createEnabledUser(true)],
+			['initiator', $this->createEnabledUser(false)],
+		]);
+
+		$this->defaultProvider
+			->expects($this->once())
+			->method('getShareById')
+			->with('42', 'recipient')
+			->willReturn($share);
+
+		$this->manager->getShareById('default:42', 'recipient');
+	}
+
 	public function testGetExpiredShareById(): void {
 		$this->expectException(ShareNotFound::class);
 
@@ -960,6 +1015,13 @@ public function createShare($id, int $type, ?Node $node, $sharedWith, $sharedBy,
 		return $share;
 	}
 
+	private function createEnabledUser(bool $enabled): IUser&MockObject {
+		$user = $this->createMock(IUser::class);
+		$user->method('isEnabled')->willReturn($enabled);
+
+		return $user;
+	}
+
 	public static function dataGeneralChecks(): array {
 		$user0 = 'user0';
 		$user2 = 'user1';
@@ -3262,6 +3324,83 @@ public function testCreateShareUser(): void {
 		$manager->createShare($share);
 	}
 
+	public function testCreateShareUserAlreadySharedReusesExistingShare(): void {
+		/** @var Manager&MockObject $manager */
+		$manager = $this->createManagerMock()
+			->onlyMethods(['generalChecks', 'userCreateChecks', 'pathCreateChecks'])
+			->getMock();
+
+		$shareOwner = $this->createMock(IUser::class);
+		$shareOwner->method('getUID')->willReturn('shareOwner');
+
+		$path = $this->createMock(File::class);
+		$path->method('getOwner')->willReturn($shareOwner);
+		$path->method('getName')->willReturn('target');
+		$path->method('getStorage')->willReturn($this->createMock(IStorage::class));
+
+		$share = $this->createShare(null, IShare::TYPE_USER, $path, 'sharedWith', 'sharedBy', null, Constants::PERMISSION_ALL);
+		$existingShare = $this->createShare('42', IShare::TYPE_USER, $path, 'sharedWith', 'shareOwner', 'shareOwner', Constants::PERMISSION_READ);
+
+		$this->config->method('getAppValue')
+			->willReturnMap([
+				['files_sharing', 'hide_disabled_user_shares', 'yes', 'yes'],
+			]);
+		$this->userManager->method('get')->willReturnMap([
+			['shareOwner', $this->createEnabledUser(true)],
+		]);
+
+		$manager->method('userCreateChecks')
+			->willThrowException(new AlreadySharedException('Already shared', $existingShare));
+
+		$this->defaultProvider->expects($this->never())
+			->method('create');
+
+		$existingShare->expects($this->once())
+			->method('setNode')
+			->with($path);
+
+		$this->assertSame($existingShare, $manager->createShare($share));
+	}
+
+	public function testCreateShareUserAlreadySharedByDisabledInitiator(): void {
+		$this->expectException(AlreadySharedException::class);
+
+		/** @var Manager&MockObject $manager */
+		$manager = $this->createManagerMock()
+			->onlyMethods(['generalChecks', 'userCreateChecks', 'pathCreateChecks'])
+			->getMock();
+
+		$shareOwner = $this->createMock(IUser::class);
+		$shareOwner->method('getUID')->willReturn('shareOwner');
+
+		$path = $this->createMock(File::class);
+		$path->method('getOwner')->willReturn($shareOwner);
+		$path->method('getName')->willReturn('target');
+		$path->method('getStorage')->willReturn($this->createMock(IStorage::class));
+
+		$share = $this->createShare(null, IShare::TYPE_USER, $path, 'sharedWith', 'shareOwner', null, Constants::PERMISSION_ALL);
+		$existingShare = $this->createShare('42', IShare::TYPE_USER, $path, 'sharedWith', 'initiator', 'shareOwner', Constants::PERMISSION_READ);
+
+		$this->config->method('getAppValue')
+			->willReturnMap([
+				['files_sharing', 'hide_disabled_user_shares', 'yes', 'yes'],
+			]);
+		$this->userManager->method('get')->willReturnMap([
+			['shareOwner', $this->createEnabledUser(true)],
+			['initiator', $this->createEnabledUser(false)],
+		]);
+
+		$manager->method('userCreateChecks')
+			->willThrowException(new AlreadySharedException('Already shared', $existingShare));
+
+		$this->defaultProvider->expects($this->never())
+			->method('create');
+		$this->dispatcher->expects($this->never())
+			->method('dispatchTyped');
+
+		$manager->createShare($share);
+	}
+
 	public function testCreateShareGroup(): void {
 		$manager = $this->createManagerMock()
 			->onlyMethods(['generalChecks', 'groupCreateChecks', 'pathCreateChecks', 'validateExpirationDateInternal'])
@@ -3686,6 +3825,86 @@ public function testGetSharesByOwnerless(): void {
 		$this->assertSame($share, $shares[0]);
 	}
 
+	public function testGetSharesByOfDisabledInitiatorAsShareOwner(): void {
+		$this->config->method('getAppValue')
+			->willReturnMap([
+				['files_sharing', 'hide_disabled_user_shares', 'yes', 'yes'],
+			]);
+
+		$share = $this->manager->newShare();
+		$share->setShareType(IShare::TYPE_USER)
+			->setShareOwner('owner')
+			->setSharedBy('initiator')
+			->setSharedWith('recipient');
+
+		$this->userManager->method('get')->willReturnMap([
+			['owner', $this->createEnabledUser(true)],
+			['initiator', $this->createEnabledUser(false)],
+		]);
+
+		$this->defaultProvider->expects($this->once())
+			->method('getSharesBy')
+			->willReturn([$share]);
+
+		$shares = $this->manager->getSharesBy('owner', IShare::TYPE_USER, $this->createMock(Folder::class), true, -1, 0);
+
+		$this->assertCount(1, $shares);
+		$this->assertSame($share, $shares[0]);
+	}
+
+	public function testGetSharesByOfDisabledInitiatorAsOtherUser(): void {
+		$this->config->method('getAppValue')
+			->willReturnMap([
+				['files_sharing', 'hide_disabled_user_shares', 'yes', 'yes'],
+			]);
+
+		$share = $this->manager->newShare();
+		$share->setShareType(IShare::TYPE_USER)
+			->setShareOwner('owner')
+			->setSharedBy('initiator')
+			->setSharedWith('recipient');
+
+		$this->userManager->method('get')->willReturnMap([
+			['owner', $this->createEnabledUser(true)],
+			['initiator', $this->createEnabledUser(false)],
+			['resharer', $this->createEnabledUser(true)],
+		]);
+
+		$this->defaultProvider->expects($this->once())
+			->method('getSharesBy')
+			->willReturn([$share]);
+
+		$shares = $this->manager->getSharesBy('resharer', IShare::TYPE_USER, $this->createMock(Folder::class), true, -1, 0);
+
+		$this->assertCount(0, $shares);
+	}
+
+	public function testGetSharedWithOfDisabledInitiator(): void {
+		$this->config->method('getAppValue')
+			->willReturnMap([
+				['files_sharing', 'hide_disabled_user_shares', 'yes', 'yes'],
+			]);
+
+		$share = $this->manager->newShare();
+		$share->setShareType(IShare::TYPE_USER)
+			->setShareOwner('owner')
+			->setSharedBy('initiator')
+			->setSharedWith('recipient');
+
+		$this->userManager->method('get')->willReturnMap([
+			['owner', $this->createEnabledUser(true)],
+			['initiator', $this->createEnabledUser(false)],
+		]);
+
+		$this->defaultProvider->expects($this->once())
+			->method('getSharedWith')
+			->willReturn([$share]);
+
+		$shares = $this->manager->getSharedWith('recipient', IShare::TYPE_USER);
+
+		$this->assertCount(0, $shares);
+	}
+
 	/**
 	 * Test to ensure we correctly remove expired link shares
 	 *