BMC/Intel-BMC/linux.git/fs, branch v4.18.18

fscache: Fix out of bound read in long cookie keys

2018-11-10T15:49:45+00:00

commit fa520c47eaa15b9baa8ad66ac18da4a31679693b upstream. fscache_set_key() can incur an out-of-bounds read, reported by KASAN: BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x5b3/0x680 [fscache] Read of size 4 at addr ffff88084ff056d4 by task mount.nfs/32615 and also reported by syzbot at https://lkml.org/lkml/2018/7/8/236 BUG: KASAN: slab-out-of-bounds in fscache_set_key fs/fscache/cookie.c:120 [inline] BUG: KASAN: slab-out-of-bounds in fscache_alloc_cookie+0x7a9/0x880 fs/fscache/cookie.c:171 Read of size 4 at addr ffff8801d3cc8bb4 by task syz-executor907/4466 This happens for any index_key_len which is not divisible by 4 and is larger than the size of the inline key, because the code allocates exactly index_key_len for the key buffer, but the hashing loop is stepping through it 4 bytes (u32) at a time in the buf[] array. Fix this by calculating how many u32 buffers we'll need by using DIV_ROUND_UP, and then using kcalloc() to allocate a precleared allocation buffer to hold the index_key, then using that same count as the hashing index limit. Fixes: ec0328e46d6e ("fscache: Maintain a catalogue of allocated cookies") Reported-by: syzbot+a95b989b2dde8e806af8@syzkaller.appspotmail.com Signed-off-by: Eric Sandeen Cc: stable Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman

cachefiles: fix the race between cachefiles_bury_object() and rmdir(2)

2018-11-10T15:49:45+00:00

commit 169b803397499be85bdd1e3d07d6f5e3d4bd669e upstream. the victim might've been rmdir'ed just before the lock_rename(); unlike the normal callers, we do not look the source up after the parents are locked - we know it beforehand and just recheck that it's still the child of what used to be its parent. Unfortunately, the check is too weak - we don't spot a dead directory since its ->d_parent is unchanged, dentry is positive, etc. So we sail all the way to ->rename(), with hosting filesystems _not_ expecting to be asked renaming an rmdir'ed subdirectory. The fix is easy, fortunately - the lock on parent is sufficient for making IS_DEADDIR() on child safe. Cc: stable@vger.kernel.org Fixes: 9ae326a69004 (CacheFiles: A cache that backs onto a mounted filesystem) Signed-off-by: Al Viro Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman

fscache: Fix incomplete initialisation of inline key space

2018-11-10T15:49:45+00:00

commit 1ff22883b0b2f7a73eb2609ffe879c9fd96f6328 upstream. The inline key in struct rxrpc_cookie is insufficiently initialized, zeroing only 3 of the 4 slots, therefore an index_key_len between 13 and 15 bytes will end up hashing uninitialized memory because the memcpy only partially fills the last buf[] element. Fix this by clearing fscache_cookie objects on allocation rather than using the slab constructor to initialise them. We're going to pretty much fill in the entire struct anyway, so bringing it into our dcache writably shouldn't incur much overhead. This removes the need to do clearance in fscache_set_key() (where we aren't doing it correctly anyway). Also, we don't need to set cookie->key_len in fscache_set_key() as we already did it in the only caller, so remove that. Fixes: ec0328e46d6e ("fscache: Maintain a catalogue of allocated cookies") Reported-by: syzbot+a95b989b2dde8e806af8@syzkaller.appspotmail.com Reported-by: Eric Sandeen Cc: stable Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman

vfs: swap names of {do,vfs}_clone_file_range()

2018-11-10T15:49:44+00:00

commit a725356b6659469d182d662f22d770d83d3bc7b5 upstream. Commit 031a072a0b8a ("vfs: call vfs_clone_file_range() under freeze protection") created a wrapper do_clone_file_range() around vfs_clone_file_range() moving the freeze protection to former, so overlayfs could call the latter. The more common vfs practice is to call do_xxx helpers from vfs_xxx helpers, where freeze protecction is taken in the vfs_xxx helper, so this anomality could be a source of confusion. It seems that commit 8ede205541ff ("ovl: add reflink/copyfile/dedup support") may have fallen a victim to this confusion - ovl_clone_file_range() calls the vfs_clone_file_range() helper in the hope of getting freeze protection on upper fs, but in fact results in overlayfs allowing to bypass upper fs freeze protection. Swap the names of the two helpers to conform to common vfs practice and call the correct helpers from overlayfs and nfsd. Signed-off-by: Amir Goldstein Signed-off-by: Miklos Szeredi Fixes: 031a072a0b8a ("vfs: call vfs_clone_file_range() under freeze...") Signed-off-by: Amir Goldstein Signed-off-by: Sasha Levin

fs/fat/fatent.c: add cond_resched() to fat_count_free_clusters()

2018-11-04T13:51:51+00:00

[ Upstream commit ac081c3be3fae6d0cc3e1862507fca3862d30b67 ] On non-preempt kernels this loop can take a long time (more than 50 ticks) processing through entries. Link: http://lkml.kernel.org/r/20181010172623.57033-1-khazhy@google.com Signed-off-by: Khazhismel Kumykov Acked-by: OGAWA Hirofumi Reviewed-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

afs: Fix cell proc list

2018-11-04T13:51:51+00:00

[ Upstream commit 6b3944e42e2e554aa5a4be681ecd70dccd459114 ] Access to the list of cells by /proc/net/afs/cells has a couple of problems: (1) It should be checking against SEQ_START_TOKEN for the keying the header line. (2) It's only holding the RCU read lock, so it can't just walk over the list without following the proper RCU methods. Fix these by using an hlist instead of an ordinary list and using the appropriate accessor functions to follow it with RCU. Since the code that adds a cell to the list must also necessarily change, sort the list on insertion whilst we're at it. Fixes: 989782dcdc91 ("afs: Overhaul cell database management") Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

ocfs2: fix crash in ocfs2_duplicate_clusters_by_page()

2018-11-04T13:51:48+00:00

[ Upstream commit 69eb7765b9c6902444c89c54e7043242faf981e5 ] ocfs2_duplicate_clusters_by_page() may crash if one of the extent's pages is dirty. When a page has not been written back, it is still in dirty state. If ocfs2_duplicate_clusters_by_page() is called against the dirty page, the crash happens. To fix this bug, we can just unlock the page and wait until the page until its not dirty. The following is the backtrace: kernel BUG at /root/code/ocfs2/refcounttree.c:2961! [exception RIP: ocfs2_duplicate_clusters_by_page+822] __ocfs2_move_extent+0x80/0x450 [ocfs2] ? __ocfs2_claim_clusters+0x130/0x250 [ocfs2] ocfs2_defrag_extent+0x5b8/0x5e0 [ocfs2] __ocfs2_move_extents_range+0x2a4/0x470 [ocfs2] ocfs2_move_extents+0x180/0x3b0 [ocfs2] ? ocfs2_wait_for_recovery+0x13/0x70 [ocfs2] ocfs2_ioctl_move_extents+0x133/0x2d0 [ocfs2] ocfs2_ioctl+0x253/0x640 [ocfs2] do_vfs_ioctl+0x90/0x5f0 SyS_ioctl+0x74/0x80 do_syscall_64+0x74/0x140 entry_SYSCALL_64_after_hwframe+0x3d/0xa2 Once we find the page is dirty, we do not wait until it's clean, rather we use write_one_page() to write it back Link: http://lkml.kernel.org/r/20180829074740.9438-1-lchen@suse.com [lchen@suse.com: update comments] Link: http://lkml.kernel.org/r/20180830075041.14879-1-lchen@suse.com [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Larry Chen Acked-by: Changwei Ge Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

Revert "vfs: fix freeze protection in mnt_want_write_file() for overlayfs"

2018-10-20T07:47:09+00:00

This reverts commit 5e1002ab5c9bde81a0c1eed12f243987e98f7bd0 which was commit a6795a585929d94ca3e931bc8518f8deb8bbe627 upstream. Turns out this causes problems and was to fix a patch only in the 4.19 and newer tree. Reported-by: Amir Goldstein Cc: Miklos Szeredi Cc: Christoph Hellwig Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman

filesystem-dax: Fix dax_layout_busy_page() livelock

2018-10-18T07:18:20+00:00

commit d7782145e1ad537df4ce74e58c50f1f732a1462d upstream. In the presence of multi-order entries the typical pagevec_lookup_entries() pattern may loop forever: while (index < end && pagevec_lookup_entries(&pvec, mapping, index, min(end - index, (pgoff_t)PAGEVEC_SIZE), indices)) { ... for (i = 0; i < pagevec_count(&pvec); i++) { index = indices[i]; ... } index++; /* BUG */ } The loop updates 'index' for each index found and then increments to the next possible page to continue the lookup. However, if the last entry in the pagevec is multi-order then the next possible page index is more than 1 page away. Fix this locally for the filesystem-dax case by checking for dax-multi-order entries. Going forward new users of multi-order entries need to be similarly careful, or we need a generic way to report the page increment in the radix iterator. Fixes: 5fac7408d828 ("mm, fs, dax: handle layout changes to pinned dax...") Cc: Cc: Ross Zwisler Cc: Matthew Wilcox Reviewed-by: Jan Kara Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman

afs: Fix clearance of reply

2018-10-18T07:18:17+00:00

commit f0a7d1883d9f78ae7bf15fc258bf9a2b20f35b76 upstream. The recent patch to fix the afs_server struct leak didn't actually fix the bug, but rather fixed some of the symptoms. The problem is that an asynchronous call that holds a resource pointed to by call->reply[0] will find the pointer cleared in the call destructor, thereby preventing the resource from being cleaned up. In the case of the server record leak, the afs_fs_get_capabilities() function in devel code sets up a call with reply[0] pointing at the server record that should be altered when the result is obtained, but this was being cleared before the destructor was called, so the put in the destructor does nothing and the record is leaked. Commit f014ffb025c1 removed the additional ref obtained by afs_install_server(), but the removal of this ref is actually used by the garbage collector to mark a server record as being defunct after the record has expired through lack of use. The offending clearance of call->reply[0] upon completion in afs_process_async_call() has been there from the origin of the code, but none of the asynchronous calls actually use that pointer currently, so it should be safe to remove (note that synchronous calls don't involve this function). Fix this by the following means: (1) Revert commit f014ffb025c1. (2) Remove the clearance of reply[0] from afs_process_async_call(). Without this, afs_manage_servers() will suffer an assertion failure if it sees a server record that didn't get used because the usage count is not 1. Fixes: f014ffb025c1 ("afs: Fix afs_server struct leak") Fixes: 08e0e7c82eea ("[AF_RXRPC]: Make the in-kernel AFS filesystem use AF_RXRPC.") Signed-off-by: David Howells Cc: stable Signed-off-by: Greg Kroah-Hartman Signed-off-by: Greg Kroah-Hartman