BMC/Intel-BMC/linux.git/fs, branch v4.19.10

dax: Check page->mapping isn't NULL

2018-12-17T08:24:41+00:00

commit c93db7bb6ef3251e0ea48ade311d3e9942748e1c upstream. If we race with inode destroy, it's possible for page->mapping to be NULL before we even enter this routine, as well as after having slept waiting for the dax entry to become unlocked. Fixes: c2a7d2a11552 ("filesystem-dax: Introduce dax_lock_mapping_entry()") Cc: Reported-by: Jan Kara Signed-off-by: Matthew Wilcox Reviewed-by: Johannes Thumshirn Reviewed-by: Jan Kara Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman

flexfiles: enforce per-mirror stateid only for v4 DSes

2018-12-17T08:24:41+00:00

commit 320f35b7bf8cccf1997ca3126843535e1b95e9c4 upstream. Since commit bb21ce0ad227 we always enforce per-mirror stateid. However, this makes sense only for v4+ servers. Signed-off-by: Tigran Mkrtchyan Signed-off-by: Trond Myklebust Signed-off-by: Greg Kroah-Hartman

ocfs2: fix potential use after free

2018-12-17T08:24:41+00:00

[ Upstream commit 164f7e586739d07eb56af6f6d66acebb11f315c8 ] ocfs2_get_dentry() calls iput(inode) to drop the reference count of inode, and if the reference count hits 0, inode is freed. However, in this function, it then reads inode->i_generation, which may result in a use after free bug. Move the put operation later. Link: http://lkml.kernel.org/r/1543109237-110227-1-git-send-email-bianpan2016@163.com Fixes: 781f200cb7a("ocfs2: Remove masklog ML_EXPORT.") Signed-off-by: Pan Bian Reviewed-by: Andrew Morton Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Cc: Changwei Ge Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfsplus: do not free node before using

2018-12-17T08:24:41+00:00

[ Upstream commit c7d7d620dcbd2a1c595092280ca943f2fced7bbd ] hfs_bmap_free() frees node via hfs_bnode_put(node). However it then reads node->this when dumping error message on an error path, which may result in a use-after-free bug. This patch frees node only when it is never used. Link: http://lkml.kernel.org/r/1543053441-66942-1-git-send-email-bianpan2016@163.com Signed-off-by: Pan Bian Reviewed-by: Andrew Morton Cc: Ernesto A. Fernandez Cc: Joe Perches Cc: Viacheslav Dubeyko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

hfs: do not free node before using

2018-12-17T08:24:41+00:00

[ Upstream commit ce96a407adef126870b3f4a1b73529dd8aa80f49 ] hfs_bmap_free() frees the node via hfs_bnode_put(node). However, it then reads node->this when dumping error message on an error path, which may result in a use-after-free bug. This patch frees the node only when it is never again used. Link: http://lkml.kernel.org/r/1542963889-128825-1-git-send-email-bianpan2016@163.com Fixes: a1185ffa2fc ("HFS rewrite") Signed-off-by: Pan Bian Reviewed-by: Andrew Morton Cc: Joe Perches Cc: Ernesto A. Fernandez Cc: Viacheslav Dubeyko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

ocfs2: fix deadlock caused by ocfs2_defrag_extent()

2018-12-17T08:24:40+00:00

[ Upstream commit e21e57445a64598b29a6f629688f9b9a39e7242a ] ocfs2_defrag_extent may fall into deadlock. ocfs2_ioctl_move_extents ocfs2_ioctl_move_extents ocfs2_move_extents ocfs2_defrag_extent ocfs2_lock_allocators_move_extents ocfs2_reserve_clusters inode_lock GLOBAL_BITMAP_SYSTEM_INODE __ocfs2_flush_truncate_log inode_lock GLOBAL_BITMAP_SYSTEM_INODE As backtrace shows above, ocfs2_reserve_clusters() will call inode_lock against the global bitmap if local allocator has not sufficient cluters. Once global bitmap could meet the demand, ocfs2_reserve_cluster will return success with global bitmap locked. After ocfs2_reserve_cluster(), if truncate log is full, __ocfs2_flush_truncate_log() will definitely fall into deadlock because it needs to inode_lock global bitmap, which has already been locked. To fix this bug, we could remove from ocfs2_lock_allocators_move_extents() the code which intends to lock global allocator, and put the removed code after __ocfs2_flush_truncate_log(). ocfs2_lock_allocators_move_extents() is referred by 2 places, one is here, the other does not need the data allocator context, which means this patch does not affect the caller so far. Link: http://lkml.kernel.org/r/20181101071422.14470-1-lchen@suse.com Signed-off-by: Larry Chen Reviewed-by: Changwei Ge Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

fscache, cachefiles: remove redundant variable 'cache'

2018-12-17T08:24:40+00:00

[ Upstream commit 31ffa563833576bd49a8bf53120568312755e6e2 ] Variable 'cache' is being assigned but is never used hence it is redundant and can be removed. Cleans up clang warning: warning: variable 'cache' set but not used [-Wunused-but-set-variable] Signed-off-by: Colin Ian King Signed-off-by: David Howells Signed-off-by: Sasha Levin

cachefiles: Explicitly cast enumerated type in put_object

2018-12-17T08:24:40+00:00

[ Upstream commit b7e768b7e3522695ed36dcb48ecdcd344bd30a9b ] Clang warns when one enumerated type is implicitly converted to another. fs/cachefiles/namei.c:247:50: warning: implicit conversion from enumeration type 'enum cachefiles_obj_ref_trace' to different enumeration type 'enum fscache_obj_ref_trace' [-Wenum-conversion] cache->cache.ops->put_object(&xobject->fscache, cachefiles_obj_put_wait_retry); Silence this warning by explicitly casting to fscache_obj_ref_trace, which is also done in put_object. Reported-by: Nick Desaulniers Signed-off-by: Nathan Chancellor Signed-off-by: David Howells Signed-off-by: Sasha Levin

fscache: fix race between enablement and dropping of object

2018-12-17T08:24:40+00:00

[ Upstream commit c5a94f434c82529afda290df3235e4d85873c5b4 ] It was observed that a process blocked indefintely in __fscache_read_or_alloc_page(), waiting for FSCACHE_COOKIE_LOOKING_UP to be cleared via fscache_wait_for_deferred_lookup(). At this time, ->backing_objects was empty, which would normaly prevent __fscache_read_or_alloc_page() from getting to the point of waiting. This implies that ->backing_objects was cleared *after* __fscache_read_or_alloc_page was was entered. When an object is "killed" and then "dropped", FSCACHE_COOKIE_LOOKING_UP is cleared in fscache_lookup_failure(), then KILL_OBJECT and DROP_OBJECT are "called" and only in DROP_OBJECT is ->backing_objects cleared. This leaves a window where something else can set FSCACHE_COOKIE_LOOKING_UP and __fscache_read_or_alloc_page() can start waiting, before ->backing_objects is cleared There is some uncertainty in this analysis, but it seems to be fit the observations. Adding the wake in this patch will be handled correctly by __fscache_read_or_alloc_page(), as it checks if ->backing_objects is empty again, after waiting. Customer which reported the hang, also report that the hang cannot be reproduced with this fix. The backtrace for the blocked process looked like: PID: 29360 TASK: ffff881ff2ac0f80 CPU: 3 COMMAND: "zsh" #0 [ffff881ff43efbf8] schedule at ffffffff815e56f1 #1 [ffff881ff43efc58] bit_wait at ffffffff815e64ed #2 [ffff881ff43efc68] __wait_on_bit at ffffffff815e61b8 #3 [ffff881ff43efca0] out_of_line_wait_on_bit at ffffffff815e625e #4 [ffff881ff43efd08] fscache_wait_for_deferred_lookup at ffffffffa04f2e8f [fscache] #5 [ffff881ff43efd18] __fscache_read_or_alloc_page at ffffffffa04f2ffe [fscache] #6 [ffff881ff43efd58] __nfs_readpage_from_fscache at ffffffffa0679668 [nfs] #7 [ffff881ff43efd78] nfs_readpage at ffffffffa067092b [nfs] #8 [ffff881ff43efda0] generic_file_read_iter at ffffffff81187a73 #9 [ffff881ff43efe50] nfs_file_read at ffffffffa066544b [nfs] #10 [ffff881ff43efe70] __vfs_read at ffffffff811fc756 #11 [ffff881ff43efee8] vfs_read at ffffffff811fccfa #12 [ffff881ff43eff18] sys_read at ffffffff811fda62 #13 [ffff881ff43eff50] entry_SYSCALL_64_fastpath at ffffffff815e986e Signed-off-by: NeilBrown Signed-off-by: David Howells Signed-off-by: Sasha Levin

afs: Fix validation/callback interaction

2018-12-17T08:24:40+00:00

[ Upstream commit ae3b7361dc0ee9a425bf7d77ce211f533500b39b ] When afs_validate() is called to validate a vnode (inode), there are two unhandled cases in the fastpath at the top of the function: (1) If the vnode is promised (AFS_VNODE_CB_PROMISED is set), the break counters match and the data has expired, then there's an implicit case in which the vnode needs revalidating. This has no consequences since the default "valid = false" set at the top of the function happens to do the right thing. (2) If the vnode is not promised and it hasn't been deleted (AFS_VNODE_DELETED is not set) then there's a default case we're not handling in which the vnode is invalid. If the vnode is invalid, we need to bring cb_s_break and cb_v_break up to date before we refetch the status. As a consequence, once the server loses track of the client (ie. sufficient time has passed since we last sent it an operation), it will send us a CB.InitCallBackState* operation when we next try to talk to it. This calls afs_init_callback_state() which increments afs_server::cb_s_break, but this then doesn't propagate to the afs_vnode record. The result being that every afs_validate() call thereafter sends a status fetch operation to the server. Clarify and fix this by: (A) Setting valid in all the branches rather than initialising it at the top so that the compiler catches where we've missed. (B) Restructuring the logic in the 'promised' branch so that we set valid to false if the callback is due to expire (or has expired) and so that the final case is that the vnode is still valid. (C) Adding an else-statement that ups cb_s_break and cb_v_break if the promised and deleted cases don't match. Fixes: c435ee34551e ("afs: Overhaul the callback handling") Signed-off-by: David Howells Signed-off-by: Al Viro Signed-off-by: Sasha Levin