kernel/fs, branch linux-4.1.y

ext4: set h_journal if there is a failure starting a reserved handle

2018-05-23T01:36:37Z

[ Upstream commit b2569260d55228b617bd82aba6d0db2faeeb4116 ] If ext4 tries to start a reserved handle via jbd2_journal_start_reserved(), and the journal has been aborted, this can result in a NULL pointer dereference. This is because the fields h_journal and h_transaction in the handle structure share the same memory, via a union, so jbd2_journal_start_reserved() will clear h_journal before calling start_this_handle(). If this function fails due to an aborted handle, h_journal will still be NULL, and the call to jbd2_journal_free_reserved() will pass a NULL journal to sub_reserve_credits(). This can be reproduced by running "kvm-xfstests -c dioread_nolock generic/475". Cc: stable@kernel.org # 3.11 Fixes: 8f7d89f36829b ("jbd2: transaction reservation support") Signed-off-by: Theodore Ts'o Reviewed-by: Andreas Dilger Reviewed-by: Jan Kara Signed-off-by: Sasha Levin

jbd2: fix use after free in kjournald2()

2018-05-23T01:36:36Z

[ Upstream commit dbfcef6b0f4012c57bc0b6e0e660d5ed12a5eaed ] Below is the synchronization issue between unmount and kjournald2 contexts, which results into use after free issue in kjournald2(). Fix this issue by using journal->j_state_lock to synchronize the wait_event() done in journal_kill_thread() and the wake_up() done in kjournald2(). TASK 1: umount cmd: |--jbd2_journal_destroy() { |--journal_kill_thread() { write_lock(&journal->j_state_lock); journal->j_flags |= JBD2_UNMOUNT; ... write_unlock(&journal->j_state_lock); wake_up(&journal->j_wait_commit); TASK 2 wakes up here: kjournald2() { ... checks JBD2_UNMOUNT flag and calls goto end-loop; ... end_loop: write_unlock(&journal->j_state_lock); journal->j_task = NULL; --> If this thread gets pre-empted here, then TASK 1 wait_event will exit even before this thread is completely done. wait_event(journal->j_wait_done_commit, journal->j_task == NULL); ... write_lock(&journal->j_state_lock); write_unlock(&journal->j_state_lock); } |--kfree(journal); } } wake_up(&journal->j_wait_done_commit); --> this step now results into use after free issue. } Signed-off-by: Sahitya Tummala Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

cifs: do not allow creating sockets except with SMB1 posix exensions

2018-05-23T01:36:35Z

[ Upstream commit 1d0cffa674cfa7d185a302c8c6850fc50b893bed ] RHBZ: 1453123 Since at least the 3.10 kernel and likely a lot earlier we have not been able to create unix domain sockets in a cifs share when mounted using the SFU mount option (except when mounted with the cifs unix extensions to Samba e.g.) Trying to create a socket, for example using the af_unix command from xfstests will cause : BUG: unable to handle kernel NULL pointer dereference at 00000000 00000040 Since no one uses or depends on being able to create unix domains sockets on a cifs share the easiest fix to stop this vulnerability is to simply not allow creation of any other special files than char or block devices when sfu is used. Added update to Ronnie's patch to handle a tcon link leak, and to address a buf leak noticed by Gustavo and Colin. Acked-by: Gustavo A. R. Silva CC: Colin Ian King Reviewed-by: Pavel Shilovsky Reported-by: Eryu Guan Signed-off-by: Ronnie Sahlberg Signed-off-by: Steve French Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin

fanotify: fix logic of events on child

2018-05-23T01:36:35Z

[ Upstream commit 54a307ba8d3cd00a3902337ffaae28f436eeb1a4 ] When event on child inodes are sent to the parent inode mark and parent inode mark was not marked with FAN_EVENT_ON_CHILD, the event will not be delivered to the listener process. However, if the same process also has a mount mark, the event to the parent inode will be delivered regadless of the mount mark mask. This behavior is incorrect in the case where the mount mark mask does not contain the specific event type. For example, the process adds a mark on a directory with mask FAN_MODIFY (without FAN_EVENT_ON_CHILD) and a mount mark with mask FAN_CLOSE_NOWRITE (without FAN_ONDIR). A modify event on a file inside that directory (and inside that mount) should not create a FAN_MODIFY event, because neither of the marks requested to get that event on the file. Fixes: 1968f5eed54c ("fanotify: use both marks when possible") Cc: stable Signed-off-by: Amir Goldstein Signed-off-by: Jan Kara Signed-off-by: Sasha Levin

ext4: bugfix for mmaped pages in mpage_release_unused_pages()

2018-05-23T01:36:35Z

[ Upstream commit 4e800c0359d9a53e6bf0ab216954971b2515247f ] Pages clear buffers after ext4 delayed block allocation failed, However, it does not clean its pte_dirty flag. if the pages unmap ,in cording to the pte_dirty , unmap_page_range may try to call __set_page_dirty, which may lead to the bugon at mpage_prepare_extent_to_map:head = page_buffers(page);. This patch just call clear_page_dirty_for_io to clean pte_dirty at mpage_release_unused_pages for pages mmaped. Steps to reproduce the bug: （1） mmap a file in ext4 addr = (char *)mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0); memset(addr, 'i', 4096); （2） return EIO at ext4_writepages->mpage_map_and_submit_extent->mpage_map_one_extent which causes this log message to be print: ext4_msg(sb, KERN_CRIT, "Delayed block allocation failed for " "inode %lu at logical offset %llu with" " max blocks %u with error %d", inode->i_ino, (unsigned long long)map->m_lblk, (unsigned)map->m_len, -err); (3）Unmap the addr cause warning at __set_page_dirty:WARN_ON_ONCE(warn && !PageUptodate(page)); (4) wait for a minute,then bugon happen. Cc: stable@vger.kernel.org Signed-off-by: wangguang Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin

autofs: mount point create should honour passed in mode

2018-05-23T01:36:35Z

[ Upstream commit 1e6306652ba18723015d1b4967fe9de55f042499 ] The autofs file system mkdir inode operation blindly sets the created directory mode to S_IFDIR | 0555, ingoring the passed in mode, which can cause selinux dac_override denials. But the function also checks if the caller is the daemon (as no-one else should be able to do anything here) so there's no point in not honouring the passed in mode, allowing the daemon to set appropriate mode when required. Link: http://lkml.kernel.org/r/152361593601.8051.14014139124905996173.stgit@pluto.themaw.net Signed-off-by: Ian Kent Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

Don't leak MNT_INTERNAL away from internal mounts

2018-05-23T01:36:35Z

[ Upstream commit 16a34adb9392b2fe4195267475ab5b472e55292c ] We want it only for the stuff created by SB_KERNMOUNT mounts, *not* for their copies. As it is, creating a deep stack of bindings of /proc/*/ns/* somewhere in a new namespace and exiting yields a stack overflow. Cc: stable@kernel.org Reported-by: Alexander Aring Bisected-by: Kirill Tkhai Tested-by: Kirill Tkhai Tested-by: Alexander Aring Signed-off-by: Al Viro Signed-off-by: Sasha Levin

jffs2_kill_sb(): deal with failed allocations

2018-05-23T01:36:35Z

[ Upstream commit c66b23c2840446a82c389e4cb1a12eb2a71fa2e4 ] jffs2_fill_super() might fail to allocate jffs2_sb_info; jffs2_kill_sb() must survive that. Cc: stable@kernel.org Signed-off-by: Al Viro Signed-off-by: Sasha Levin

ext4: don't allow r/w mounts if metadata blocks overlap the superblock

2018-05-23T01:36:34Z

[ Upstream commit 18db4b4e6fc31eda838dd1c1296d67dbcb3dc957 ] If some metadata block, such as an allocation bitmap, overlaps the superblock, it's very likely that if the file system is mounted read/write, the results will not be pretty. So disallow r/w mounts for file systems corrupted in this particular way. Signed-off-by: Theodore Ts'o Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin

jbd2: if the journal is aborted then don't allow update of the log tail

2018-05-23T01:36:33Z

[ Upstream commit 85e0c4e89c1b864e763c4e3bb15d0b6d501ad5d9 ] This updates the jbd2 superblock unnecessarily, and on an abort we shouldn't truncate the log. Signed-off-by: Theodore Ts'o Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin