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* Merge tag 'trace-v5.4-rc2' of ↵Linus Torvalds2019-10-131-41/+5
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "A few tracing fixes: - Remove lockdown from tracefs itself and moved it to the trace directory. Have the open functions there do the lockdown checks. - Fix a few races with opening an instance file and the instance being deleted (Discovered during the lockdown updates). Kept separate from the clean up code such that they can be backported to stable easier. - Clean up and consolidated the checks done when opening a trace file, as there were multiple checks that need to be done, and it did not make sense having them done in each open instance. - Fix a regression in the record mcount code. - Small hw_lat detector tracer fixes. - A trace_pipe read fix due to not initializing trace_seq" * tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Initialize iter->seq after zeroing in tracing_read_pipe() tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency tracing/hwlat: Report total time spent in all NMIs during the sample recordmcount: Fix nop_mcount() function tracing: Do not create tracefs files if tracefs lockdown is in effect tracing: Add locked_down checks to the open calls of files created for tracefs tracing: Add tracing_check_open_get_tr() tracing: Have trace events system open call tracing_open_generic_tr() tracing: Get trace_array reference for available_tracers files ftrace: Get a reference counter for the trace_array on filter files tracefs: Revert ccbd54ff54e8 ("tracefs: Restrict tracefs when the kernel is locked down")
| * tracing: Do not create tracefs files if tracefs lockdown is in effectSteven Rostedt (VMware)2019-10-121-0/+4
| | | | | | | | | | | | | | | | | | | | | | If on boot up, lockdown is activated for tracefs, don't even bother creating the files. This can also prevent instances from being created if lockdown is in effect. Link: http://lkml.kernel.org/r/CAHk-=whC6Ji=fWnjh2+eS4b15TnbsS4VPVtvBOwCy1jjEG_JHQ@mail.gmail.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
| * tracefs: Revert ccbd54ff54e8 ("tracefs: Restrict tracefs when the kernel is ↵Steven Rostedt (VMware)2019-10-121-41/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | locked down") Running the latest kernel through my "make instances" stress tests, I triggered the following bug (with KASAN and kmemleak enabled): mkdir invoked oom-killer: gfp_mask=0x40cd0(GFP_KERNEL|__GFP_COMP|__GFP_RECLAIMABLE), order=0, oom_score_adj=0 CPU: 1 PID: 2229 Comm: mkdir Not tainted 5.4.0-rc2-test #325 Hardware name: MSI MS-7823/CSM-H87M-G43 (MS-7823), BIOS V1.6 02/22/2014 Call Trace: dump_stack+0x64/0x8c dump_header+0x43/0x3b7 ? trace_hardirqs_on+0x48/0x4a oom_kill_process+0x68/0x2d5 out_of_memory+0x2aa/0x2d0 __alloc_pages_nodemask+0x96d/0xb67 __alloc_pages_node+0x19/0x1e alloc_slab_page+0x17/0x45 new_slab+0xd0/0x234 ___slab_alloc.constprop.86+0x18f/0x336 ? alloc_inode+0x2c/0x74 ? irq_trace+0x12/0x1e ? tracer_hardirqs_off+0x1d/0xd7 ? __slab_alloc.constprop.85+0x21/0x53 __slab_alloc.constprop.85+0x31/0x53 ? __slab_alloc.constprop.85+0x31/0x53 ? alloc_inode+0x2c/0x74 kmem_cache_alloc+0x50/0x179 ? alloc_inode+0x2c/0x74 alloc_inode+0x2c/0x74 new_inode_pseudo+0xf/0x48 new_inode+0x15/0x25 tracefs_get_inode+0x23/0x7c ? lookup_one_len+0x54/0x6c tracefs_create_file+0x53/0x11d trace_create_file+0x15/0x33 event_create_dir+0x2a3/0x34b __trace_add_new_event+0x1c/0x26 event_trace_add_tracer+0x56/0x86 trace_array_create+0x13e/0x1e1 instance_mkdir+0x8/0x17 tracefs_syscall_mkdir+0x39/0x50 ? get_dname+0x31/0x31 vfs_mkdir+0x78/0xa3 do_mkdirat+0x71/0xb0 sys_mkdir+0x19/0x1b do_fast_syscall_32+0xb0/0xed I bisected this down to the addition of the proxy_ops into tracefs for lockdown. It appears that the allocation of the proxy_ops and then freeing it in the destroy_inode callback, is causing havoc with the memory system. Reading the documentation about destroy_inode and talking with Linus about this, this is buggy and wrong. When defining the destroy_inode() method, it is expected that the destroy_inode() will also free the inode, and not just the extra allocations done in the creation of the inode. The faulty commit causes a memory leak of the inode data structure when they are deleted. Instead of allocating the proxy_ops (and then having to free it) the checks should be done by the open functions themselves, and not hack into the tracefs directory. First revert the tracefs updates for locked_down and then later we can add the locked_down checks in the kernel/trace files. Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.home Fixes: ccbd54ff54e8 ("tracefs: Restrict tracefs when the kernel is locked down") Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
* | Merge tag 'for-linus-20191012' of git://git.kernel.dk/linux-blockLinus Torvalds2019-10-131-17/+20
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | Pull io_uring fix from Jens Axboe: "Single small fix for a regression in the sequence logic for linked commands" * tag 'for-linus-20191012' of git://git.kernel.dk/linux-block: io_uring: fix sequence logic for timeout requests
| * | io_uring: fix sequence logic for timeout requestsJens Axboe2019-10-101-17/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We have two ways a request can be deferred: 1) It's a regular request that depends on another one 2) It's a timeout that tracks completions We have a shared helper to determine whether to defer, and that attempts to make the right decision based on the request. But we only have some of this information in the caller. Un-share the two timeout/defer helpers so the caller can use the right one. Fixes: 5262f567987d ("io_uring: IORING_OP_TIMEOUT support") Reported-by: yangerkun <yangerkun@huawei.com> Reviewed-by: Jackie Liu <liuyun01@kylinos.cn> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | Merge tag 'nfs-for-5.4-2' of git://git.linux-nfs.org/projects/anna/linux-nfsLinus Torvalds2019-10-113-72/+40
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull NFS client bugfixes from Anna Schumaker: "Stable bugfixes: - Fix O_DIRECT accounting of number of bytes read/written # v4.1+ Other fixes: - Fix nfsi->nrequests count error on nfs_inode_remove_request() - Remove redundant mirror tracking in O_DIRECT - Fix leak of clp->cl_acceptor string - Fix race to sk_err after xs_error_report" * tag 'nfs-for-5.4-2' of git://git.linux-nfs.org/projects/anna/linux-nfs: SUNRPC: fix race to sk_err after xs_error_report NFSv4: Fix leak of clp->cl_acceptor string NFS: Remove redundant mirror tracking in O_DIRECT NFS: Fix O_DIRECT accounting of number of bytes read/written nfs: Fix nfsi->nrequests count error on nfs_inode_remove_request
| * | | NFSv4: Fix leak of clp->cl_acceptor stringChuck Lever2019-10-101-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Our client can issue multiple SETCLIENTID operations to the same server in some circumstances. Ensure that calls to nfs4_proc_setclientid() after the first one do not overwrite the previously allocated cl_acceptor string. unreferenced object 0xffff888461031800 (size 32): comm "mount.nfs", pid 2227, jiffies 4294822467 (age 1407.749s) hex dump (first 32 bytes): 6e 66 73 40 6b 6c 69 6d 74 2e 69 62 2e 31 30 31 nfs@klimt.ib.101 35 67 72 61 6e 67 65 72 2e 6e 65 74 00 00 00 00 5granger.net.... backtrace: [<00000000ab820188>] __kmalloc+0x128/0x176 [<00000000eeaf4ec8>] gss_stringify_acceptor+0xbd/0x1a7 [auth_rpcgss] [<00000000e85e3382>] nfs4_proc_setclientid+0x34e/0x46c [nfsv4] [<000000003d9cf1fa>] nfs40_discover_server_trunking+0x7a/0xed [nfsv4] [<00000000b81c3787>] nfs4_discover_server_trunking+0x81/0x244 [nfsv4] [<000000000801b55f>] nfs4_init_client+0x1b0/0x238 [nfsv4] [<00000000977daf7f>] nfs4_set_client+0xfe/0x14d [nfsv4] [<0000000053a68a2a>] nfs4_create_server+0x107/0x1db [nfsv4] [<0000000088262019>] nfs4_remote_mount+0x2c/0x59 [nfsv4] [<00000000e84a2fd0>] legacy_get_tree+0x2d/0x4c [<00000000797e947c>] vfs_get_tree+0x20/0xc7 [<00000000ecabaaa8>] fc_mount+0xe/0x36 [<00000000f15fafc2>] vfs_kern_mount+0x74/0x8d [<00000000a3ff4e26>] nfs_do_root_mount+0x8a/0xa3 [nfsv4] [<00000000d1c2b337>] nfs4_try_mount+0x58/0xad [nfsv4] [<000000004c9bddee>] nfs_fs_mount+0x820/0x869 [nfs] Fixes: f11b2a1cfbf5 ("nfs4: copy acceptor name from context ... ") Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * | | NFS: Remove redundant mirror tracking in O_DIRECTTrond Myklebust2019-10-091-42/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We no longer need the extra mirror length tracking in the O_DIRECT code, as we are able to track the maximum contiguous length in dreq->max_count. Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * | | NFS: Fix O_DIRECT accounting of number of bytes read/writtenTrond Myklebust2019-10-091-35/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a series of O_DIRECT reads or writes are truncated, either due to eof or due to an error, then we should return the number of contiguous bytes that were received/sent starting at the offset specified by the application. Currently, we are failing to correctly check contiguity, and so we're failing the generic/465 in xfstests when the race between the read and write RPCs causes the file to get extended while the 2 reads are outstanding. If the first read RPC call wins the race and returns with eof set, we should treat the second read RPC as being truncated. Reported-by: Su Yanjun <suyj.fnst@cn.fujitsu.com> Fixes: 1ccbad9f9f9bd ("nfs: fix DIO good bytes calculation") Cc: stable@vger.kernel.org # 4.1+ Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
| * | | nfs: Fix nfsi->nrequests count error on nfs_inode_remove_requestZhangXiaoxu2019-10-021-2/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When xfstests testing, there are some WARNING as below: WARNING: CPU: 0 PID: 6235 at fs/nfs/inode.c:122 nfs_clear_inode+0x9c/0xd8 Modules linked in: CPU: 0 PID: 6235 Comm: umount.nfs Hardware name: linux,dummy-virt (DT) pstate: 60000005 (nZCv daif -PAN -UAO) pc : nfs_clear_inode+0x9c/0xd8 lr : nfs_evict_inode+0x60/0x78 sp : fffffc000f68fc00 x29: fffffc000f68fc00 x28: fffffe00c53155c0 x27: fffffe00c5315000 x26: fffffc0009a63748 x25: fffffc000f68fd18 x24: fffffc000bfaaf40 x23: fffffc000936d3c0 x22: fffffe00c4ff5e20 x21: fffffc000bfaaf40 x20: fffffe00c4ff5d10 x19: fffffc000c056000 x18: 000000000000003c x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000040 x14: 0000000000000228 x13: fffffc000c3a2000 x12: 0000000000000045 x11: 0000000000000000 x10: 0000000000000000 x9 : 0000000000000000 x8 : 0000000000000000 x7 : 0000000000000000 x6 : fffffc00084b027c x5 : fffffc0009a64000 x4 : fffffe00c0e77400 x3 : fffffc000c0563a8 x2 : fffffffffffffffb x1 : 000000000000764e x0 : 0000000000000001 Call trace: nfs_clear_inode+0x9c/0xd8 nfs_evict_inode+0x60/0x78 evict+0x108/0x380 dispose_list+0x70/0xa0 evict_inodes+0x194/0x210 generic_shutdown_super+0xb0/0x220 nfs_kill_super+0x40/0x88 deactivate_locked_super+0xb4/0x120 deactivate_super+0x144/0x160 cleanup_mnt+0x98/0x148 __cleanup_mnt+0x38/0x50 task_work_run+0x114/0x160 do_notify_resume+0x2f8/0x308 work_pending+0x8/0x14 The nrequest should be increased/decreased only if PG_INODE_REF flag was setted. But in the nfs_inode_remove_request function, it maybe decrease when no PG_INODE_REF flag, this maybe lead nrequests count error. Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: ZhangXiaoxu <zhangxiaoxu5@huawei.com> Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
* | | | Merge tag '5.4-rc2-smb3' of git://git.samba.org/sfrench/cifs-2.6Linus Torvalds2019-10-119-40/+57
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull cifs fixes from Steve French: "Eight small SMB3 fixes, four for stable, and important fix for the recent regression introduced by filesystem timestamp range patches" * tag '5.4-rc2-smb3' of git://git.samba.org/sfrench/cifs-2.6: CIFS: Force reval dentry if LOOKUP_REVAL flag is set CIFS: Force revalidate inode when dentry is stale smb3: Fix regression in time handling smb3: remove noisy debug message and minor cleanup CIFS: Gracefully handle QueryInfo errors during open cifs: use cifsInodeInfo->open_file_lock while iterating to avoid a panic fs: cifs: mute -Wunused-const-variable message smb3: cleanup some recent endian errors spotted by updated sparse
| * | | | CIFS: Force reval dentry if LOOKUP_REVAL flag is setPavel Shilovsky2019-10-091-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Mark inode for force revalidation if LOOKUP_REVAL flag is set. This tells the client to actually send a QueryInfo request to the server to obtain the latest metadata in case a directory or a file were changed remotely. Only do that if the client doesn't have a lease for the file to avoid unneeded round trips to the server. Cc: <stable@vger.kernel.org> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | CIFS: Force revalidate inode when dentry is stalePavel Shilovsky2019-10-091-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently the client indicates that a dentry is stale when inode numbers or type types between a local inode and a remote file don't match. If this is the case attributes is not being copied from remote to local, so, it is already known that the local copy has stale metadata. That's why the inode needs to be marked for revalidation in order to tell the VFS to lookup the dentry again before openning a file. This prevents unexpected stale errors to be returned to the user space when openning a file. Cc: <stable@vger.kernel.org> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | smb3: Fix regression in time handlingSteve French2019-10-091-8/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Fixes: cb7a69e60590 ("cifs: Initialize filesystem timestamp ranges") Only very old servers (e.g. OS/2 and DOS) did not support DCE TIME (100 nanosecond granularity). Fix the checks used to set minimum and maximum times. Fixes xfstest generic/258 (on 5.4-rc1 and later) CC: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | smb3: remove noisy debug message and minor cleanupSteve French2019-10-083-9/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Message was intended only for developer temporary build In addition cleanup two minor warnings noticed by Coverity and a trivial change to workaround a sparse warning Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
| * | | | CIFS: Gracefully handle QueryInfo errors during openPavel Shilovsky2019-10-061-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently if the client identifies problems when processing metadata returned in CREATE response, the open handle is being leaked. This causes multiple problems like a file missing a lease break by that client which causes high latencies to other clients accessing the file. Another side-effect of this is that the file can't be deleted. Fix this by closing the file after the client hits an error after the file was opened and the open descriptor wasn't returned to the user space. Also convert -ESTALE to -EOPENSTALE to allow the VFS to revalidate a dentry and retry the open. Cc: <stable@vger.kernel.org> Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | cifs: use cifsInodeInfo->open_file_lock while iterating to avoid a panicDave Wysochanski2019-10-061-16/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 487317c99477 ("cifs: add spinlock for the openFileList to cifsInodeInfo") added cifsInodeInfo->open_file_lock spin_lock to protect the openFileList, but missed a few places where cifs_inode->openFileList was enumerated. Change these remaining tcon->open_file_lock to cifsInodeInfo->open_file_lock to avoid panic in is_size_safe_to_change. [17313.245641] RIP: 0010:is_size_safe_to_change+0x57/0xb0 [cifs] [17313.245645] Code: 68 40 48 89 ef e8 19 67 b7 f1 48 8b 43 40 48 8d 4b 40 48 8d 50 f0 48 39 c1 75 0f eb 47 48 8b 42 10 48 8d 50 f0 48 39 c1 74 3a <8b> 80 88 00 00 00 83 c0 01 a8 02 74 e6 48 89 ef c6 07 00 0f 1f 40 [17313.245649] RSP: 0018:ffff94ae1baefa30 EFLAGS: 00010202 [17313.245654] RAX: dead000000000100 RBX: ffff88dc72243300 RCX: ffff88dc72243340 [17313.245657] RDX: dead0000000000f0 RSI: 00000000098f7940 RDI: ffff88dd3102f040 [17313.245659] RBP: ffff88dd3102f040 R08: 0000000000000000 R09: ffff94ae1baefc40 [17313.245661] R10: ffffcdc8bb1c4e80 R11: ffffcdc8b50adb08 R12: 00000000098f7940 [17313.245663] R13: ffff88dc72243300 R14: ffff88dbc8f19600 R15: ffff88dc72243428 [17313.245667] FS: 00007fb145485700(0000) GS:ffff88dd3e000000(0000) knlGS:0000000000000000 [17313.245670] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [17313.245672] CR2: 0000026bb46c6000 CR3: 0000004edb110003 CR4: 00000000007606e0 [17313.245753] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [17313.245756] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [17313.245759] PKRU: 55555554 [17313.245761] Call Trace: [17313.245803] cifs_fattr_to_inode+0x16b/0x580 [cifs] [17313.245838] cifs_get_inode_info+0x35c/0xa60 [cifs] [17313.245852] ? kmem_cache_alloc_trace+0x151/0x1d0 [17313.245885] cifs_open+0x38f/0x990 [cifs] [17313.245921] ? cifs_revalidate_dentry_attr+0x3e/0x350 [cifs] [17313.245953] ? cifsFileInfo_get+0x30/0x30 [cifs] [17313.245960] ? do_dentry_open+0x132/0x330 [17313.245963] do_dentry_open+0x132/0x330 [17313.245969] path_openat+0x573/0x14d0 [17313.245974] do_filp_open+0x93/0x100 [17313.245979] ? __check_object_size+0xa3/0x181 [17313.245986] ? audit_alloc_name+0x7e/0xd0 [17313.245992] do_sys_open+0x184/0x220 [17313.245999] do_syscall_64+0x5b/0x1b0 Fixes: 487317c99477 ("cifs: add spinlock for the openFileList to cifsInodeInfo") CC: Stable <stable@vger.kernel.org> Signed-off-by: Dave Wysochanski <dwysocha@redhat.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | fs: cifs: mute -Wunused-const-variable messageAustin Kim2019-10-061-4/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After 'Initial git repository build' commit, 'mapping_table_ERRHRD' variable has not been used. So 'mapping_table_ERRHRD' const variable could be removed to mute below warning message: fs/cifs/netmisc.c:120:40: warning: unused variable 'mapping_table_ERRHRD' [-Wunused-const-variable] static const struct smb_to_posix_error mapping_table_ERRHRD[] = { ^ Signed-off-by: Austin Kim <austindh.kim@gmail.com> Signed-off-by: Steve French <stfrench@microsoft.com>
| * | | | smb3: cleanup some recent endian errors spotted by updated sparseSteve French2019-10-063-2/+7
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that sparse has been fixed, it spotted a couple recent minor endian errors (and removed one additional sparse warning). Thanks to Luc Van Oostenryck for his help fixing sparse. Signed-off-by: Steve French <stfrench@microsoft.com> Reviewed-by: Ronnie Sahlberg <lsahlber@redhat.com>
* | | | Merge tag 'for-linus-20191010' of git://git.kernel.dk/linux-blockLinus Torvalds2019-10-111-14/+10
|\ \ \ \ | | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull block fixes from Jens Axboe: - Fix wbt performance regression introduced with the blk-rq-qos refactoring (Harshad) - Fix io_uring fileset removal inadvertently killing the workqueue (me) - Fix io_uring typo in linked command nonblock submission (Pavel) - Remove spurious io_uring wakeups on request free (Pavel) - Fix null_blk zoned command error return (Keith) - Don't use freezable workqueues for backing_dev, also means we can revert a previous libata hack (Mika) - Fix nbd sysfs mutex dropped too soon at removal time (Xiubo) * tag 'for-linus-20191010' of git://git.kernel.dk/linux-block: nbd: fix possible sysfs duplicate warning null_blk: Fix zoned command return code io_uring: only flush workqueues on fileset removal io_uring: remove wait loop spurious wakeups blk-wbt: fix performance regression in wbt scale_up/scale_down Revert "libata, freezer: avoid block device removal while system is frozen" bdi: Do not use freezable workqueue io_uring: fix reversed nonblock flag for link submission
| * | | io_uring: only flush workqueues on fileset removalJens Axboe2019-10-091-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We should not remove the workqueue, we just need to ensure that the workqueues are synced. The workqueues are torn down on ctx removal. Cc: stable@vger.kernel.org Fixes: 6b06314c47e1 ("io_uring: add file set registration") Reported-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: remove wait loop spurious wakeupsPavel Begunkov2019-10-071-12/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Any changes interesting to tasks waiting in io_cqring_wait() are commited with io_cqring_ev_posted(). However, io_ring_drop_ctx_refs() also tries to do that but with no reason, that means spurious wakeups every io_free_req() and io_uring_enter(). Just use percpu_ref_put() instead. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
| * | | io_uring: fix reversed nonblock flag for link submissionPavel Begunkov2019-10-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | io_queue_link_head() accepts @force_nonblock flag, but io_ring_submit() passes something opposite. Fixes: c576666863b78 ("io_uring: optimize submit_and_wait API") Reported-by: kbuild test robot <lkp@intel.com> Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
* | | | Merge tag 'xfs-5.4-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linuxLinus Torvalds2019-10-1010-31/+29
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Pull xfs fixes from Darrick Wong: "A couple of small code cleanups and bug fixes for rounding errors, metadata logging errors, and an extra layer of safeguards against leaking memory contents. - Fix a rounding error in the fallocate code - Minor code cleanups - Make sure to zero memory buffers before formatting metadata blocks - Fix a few places where we forgot to log an inode metadata update - Remove broken error handling that tried to clean up after a failure but still got it wrong" * tag 'xfs-5.4-fixes-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux: xfs: move local to extent inode logging into bmap helper xfs: remove broken error handling on failed attr sf to leaf change xfs: log the inode on directory sf to block format change xfs: assure zeroed memory buffers for certain kmem allocations xfs: removed unused error variable from xchk_refcountbt_rec xfs: remove unused flags arg from xfs_get_aghdr_buf() xfs: Fix tail rounding in xfs_alloc_file_space()
| * | | | xfs: move local to extent inode logging into bmap helperBrian Foster2019-10-094-7/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The callers of xfs_bmap_local_to_extents_empty() log the inode external to the function, yet this function is where the on-disk format value is updated. Push the inode logging down into the function itself to help prevent future mistakes. Note that internal bmap callers track the inode logging flags independently and thus may log the inode core twice due to this change. This is harmless, so leave this code around for consistency with the other attr fork conversion functions. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
| * | | | xfs: remove broken error handling on failed attr sf to leaf changeBrian Foster2019-10-091-17/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | xfs_attr_shortform_to_leaf() attempts to put the shortform fork back together after a failed attempt to convert from shortform to leaf format. While this code reallocates and copies back the shortform attr fork data, it never resets the inode format field back to local format. Further, now that the inode is properly logged after the initial switch from local format, any error that triggers the recovery code will eventually abort the transaction and shutdown the fs. Therefore, remove the broken and unnecessary error handling code. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
| * | | | xfs: log the inode on directory sf to block format changeBrian Foster2019-10-092-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When a directory changes from shortform (sf) to block format, the sf format is copied to a temporary buffer, the inode format is modified and the updated format filled with the dentries from the temporary buffer. If the inode format is modified and attempt to grow the inode fails (due to I/O error, for example), it is possible to return an error while leaving the directory in an inconsistent state and with an otherwise clean transaction. This results in corruption of the associated directory and leads to xfs_dabuf_map() errors as subsequent lookups cannot accurately determine the format of the directory. This problem is reproduced occasionally by generic/475. The fundamental problem is that xfs_dir2_sf_to_block() changes the on-disk inode format without logging the inode. The inode is eventually logged by the bmapi layer in the common case, but error checking introduces the possibility of failing the high level request before this happens. Update both of the dir2 and attr callers of xfs_bmap_local_to_extents_empty() to log the inode core as consistent with the bmap local to extent format change codepath. This ensures that any subsequent errors after the format has changed cause the transaction to abort. Signed-off-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
| * | | | xfs: assure zeroed memory buffers for certain kmem allocationsBill O'Donnell2019-10-063-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Guarantee zeroed memory buffers for cases where potential memory leak to disk can occur. In these cases, kmem_alloc is used and doesn't zero the buffer, opening the possibility of information leakage to disk. Use existing infrastucture (xfs_buf_allocate_memory) to obtain the already zeroed buffer from kernel memory. This solution avoids the performance issue that would occur if a wholesale change to replace kmem_alloc with kmem_zalloc was done. Signed-off-by: Bill O'Donnell <billodo@redhat.com> [darrick: fix bitwise complaint about kmflag_mask] Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
| * | | | xfs: removed unused error variable from xchk_refcountbt_recAliasgar Surti2019-10-061-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Removed unused error variable. Instead of using error variable, returned the value directly as it wasn't updated. Signed-off-by: Aliasgar Surti <aliasgar.surti500@gmail.com> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
| * | | | xfs: remove unused flags arg from xfs_get_aghdr_buf()Eric Sandeen2019-10-061-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The flags arg is always passed as zero, so remove it. (xfs_buf_get_uncached takes flags to support XBF_NO_IOACCT for the sb, but that should never be relevant for xfs_get_aghdr_buf) Signed-off-by: Eric Sandeen <sandeen@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
| * | | | xfs: Fix tail rounding in xfs_alloc_file_space()Max Reitz2019-10-061-1/+3
| | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | To ensure that all blocks touched by the range [offset, offset + count) are allocated, we need to calculate the block count from the difference of the range end (rounded up) and the range start (rounded down). Before this patch, we just round up the byte count, which may lead to unaligned ranges not being fully allocated: $ touch test_file $ block_size=$(stat -fc '%S' test_file) $ fallocate -o $((block_size / 2)) -l $block_size test_file $ xfs_bmap test_file test_file: 0: [0..7]: 1396264..1396271 1: [8..15]: hole There should not be a hole there. Instead, the first two blocks should be fully allocated. With this patch applied, the result is something like this: $ touch test_file $ block_size=$(stat -fc '%S' test_file) $ fallocate -o $((block_size / 2)) -l $block_size test_file $ xfs_bmap test_file test_file: 0: [0..15]: 11024..11039 Signed-off-by: Max Reitz <mreitz@redhat.com> Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
* | | | Merge tag 'for-5.4-rc2-tag' of ↵Linus Torvalds2019-10-106-13/+49
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux Pull btrfs fixes from David Sterba: "A few more stabitly fixes, one build warning fix. - fix inode allocation under NOFS context - fix leak in fiemap due to concurrent append writes - fix log-root tree updates - fix balance convert of single profile on 32bit architectures - silence false positive warning on old GCCs (code moved in rc1)" * tag 'for-5.4-rc2-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux: btrfs: silence maybe-uninitialized warning in clone_range btrfs: fix uninitialized ret in ref-verify btrfs: allocate new inode in NOFS context btrfs: fix balance convert to single on 32-bit host CPUs btrfs: fix incorrect updating of log root tree Btrfs: fix memory leak due to concurrent append writes with fiemap
| * | | | btrfs: silence maybe-uninitialized warning in clone_rangeAustin Kim2019-10-081-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | GCC throws warning message as below: ‘clone_src_i_size’ may be used uninitialized in this function [-Wmaybe-uninitialized] #define IS_ALIGNED(x, a) (((x) & ((typeof(x))(a) - 1)) == 0) ^ fs/btrfs/send.c:5088:6: note: ‘clone_src_i_size’ was declared here u64 clone_src_i_size; ^ The clone_src_i_size is only used as call-by-reference in a call to get_inode_info(). Silence the warning by initializing clone_src_i_size to 0. Note that the warning is a false positive and reported by older versions of GCC (eg. 7.x) but not eg 9.x. As there have been numerous people, the patch is applied. Setting clone_src_i_size to 0 does not otherwise make sense and would not do any action in case the code changes in the future. Signed-off-by: Austin Kim <austindh.kim@gmail.com> Reviewed-by: David Sterba <dsterba@suse.com> [ add note ] Signed-off-by: David Sterba <dsterba@suse.com>
| * | | | btrfs: fix uninitialized ret in ref-verifyJosef Bacik2019-10-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Coverity caught a case where we could return with a uninitialized value in ret in process_leaf. This is actually pretty likely because we could very easily run into a block group item key and have a garbage value in ret and think there was an errror. Fix this by initializing ret to 0. Reported-by: Colin Ian King <colin.king@canonical.com> Fixes: fd708b81d972 ("Btrfs: add a extent ref verify tool") CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | | btrfs: allocate new inode in NOFS contextJosef Bacik2019-10-011-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A user reported a lockdep splat ====================================================== WARNING: possible circular locking dependency detected 5.2.11-gentoo #2 Not tainted ------------------------------------------------------ kswapd0/711 is trying to acquire lock: 000000007777a663 (sb_internal){.+.+}, at: start_transaction+0x3a8/0x500 but task is already holding lock: 000000000ba86300 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x30 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (fs_reclaim){+.+.}: kmem_cache_alloc+0x1f/0x1c0 btrfs_alloc_inode+0x1f/0x260 alloc_inode+0x16/0xa0 new_inode+0xe/0xb0 btrfs_new_inode+0x70/0x610 btrfs_symlink+0xd0/0x420 vfs_symlink+0x9c/0x100 do_symlinkat+0x66/0xe0 do_syscall_64+0x55/0x1c0 entry_SYSCALL_64_after_hwframe+0x49/0xbe -> #0 (sb_internal){.+.+}: __sb_start_write+0xf6/0x150 start_transaction+0x3a8/0x500 btrfs_commit_inode_delayed_inode+0x59/0x110 btrfs_evict_inode+0x19e/0x4c0 evict+0xbc/0x1f0 inode_lru_isolate+0x113/0x190 __list_lru_walk_one.isra.4+0x5c/0x100 list_lru_walk_one+0x32/0x50 prune_icache_sb+0x36/0x80 super_cache_scan+0x14a/0x1d0 do_shrink_slab+0x131/0x320 shrink_node+0xf7/0x380 balance_pgdat+0x2d5/0x640 kswapd+0x2ba/0x5e0 kthread+0x147/0x160 ret_from_fork+0x24/0x30 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(fs_reclaim); lock(sb_internal); lock(fs_reclaim); lock(sb_internal); *** DEADLOCK *** 3 locks held by kswapd0/711: #0: 000000000ba86300 (fs_reclaim){+.+.}, at: __fs_reclaim_acquire+0x0/0x30 #1: 000000004a5100f8 (shrinker_rwsem){++++}, at: shrink_node+0x9a/0x380 #2: 00000000f956fa46 (&type->s_umount_key#30){++++}, at: super_cache_scan+0x35/0x1d0 stack backtrace: CPU: 7 PID: 711 Comm: kswapd0 Not tainted 5.2.11-gentoo #2 Hardware name: Dell Inc. Precision Tower 3620/0MWYPT, BIOS 2.4.2 09/29/2017 Call Trace: dump_stack+0x85/0xc7 print_circular_bug.cold.40+0x1d9/0x235 __lock_acquire+0x18b1/0x1f00 lock_acquire+0xa6/0x170 ? start_transaction+0x3a8/0x500 __sb_start_write+0xf6/0x150 ? start_transaction+0x3a8/0x500 start_transaction+0x3a8/0x500 btrfs_commit_inode_delayed_inode+0x59/0x110 btrfs_evict_inode+0x19e/0x4c0 ? var_wake_function+0x20/0x20 evict+0xbc/0x1f0 inode_lru_isolate+0x113/0x190 ? discard_new_inode+0xc0/0xc0 __list_lru_walk_one.isra.4+0x5c/0x100 ? discard_new_inode+0xc0/0xc0 list_lru_walk_one+0x32/0x50 prune_icache_sb+0x36/0x80 super_cache_scan+0x14a/0x1d0 do_shrink_slab+0x131/0x320 shrink_node+0xf7/0x380 balance_pgdat+0x2d5/0x640 kswapd+0x2ba/0x5e0 ? __wake_up_common_lock+0x90/0x90 kthread+0x147/0x160 ? balance_pgdat+0x640/0x640 ? __kthread_create_on_node+0x160/0x160 ret_from_fork+0x24/0x30 This is because btrfs_new_inode() calls new_inode() under the transaction. We could probably move the new_inode() outside of this but for now just wrap it in memalloc_nofs_save(). Reported-by: Zdenek Sojka <zsojka@seznam.cz> Fixes: 712e36c5f2a7 ("btrfs: use GFP_KERNEL in btrfs_alloc_inode") CC: stable@vger.kernel.org # 4.16+ Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | | btrfs: fix balance convert to single on 32-bit host CPUsZygo Blaxell2019-10-011-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, the command: btrfs balance start -dconvert=single,soft . on a Raspberry Pi produces the following kernel message: BTRFS error (device mmcblk0p2): balance: invalid convert data profile single This fails because we use is_power_of_2(unsigned long) to validate the new data profile, the constant for 'single' profile uses bit 48, and there are only 32 bits in a long on ARM. Fix by open-coding the check using u64 variables. Tested by completing the original balance command on several Raspberry Pis. Fixes: 818255feece6 ("btrfs: use common helper instead of open coding a bit test") CC: stable@vger.kernel.org # 4.20+ Signed-off-by: Zygo Blaxell <ce3g8jdj@umail.furryterror.org> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | | btrfs: fix incorrect updating of log root treeJosef Bacik2019-10-011-9/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We've historically had reports of being unable to mount file systems because the tree log root couldn't be read. Usually this is the "parent transid failure", but could be any of the related errors, including "fsid mismatch" or "bad tree block", depending on which block got allocated. The modification of the individual log root items are serialized on the per-log root root_mutex. This means that any modification to the per-subvol log root_item is completely protected. However we update the root item in the log root tree outside of the log root tree log_mutex. We do this in order to allow multiple subvolumes to be updated in each log transaction. This is problematic however because when we are writing the log root tree out we update the super block with the _current_ log root node information. Since these two operations happen independently of each other, you can end up updating the log root tree in between writing out the dirty blocks and setting the super block to point at the current root. This means we'll point at the new root node that hasn't been written out, instead of the one we should be pointing at. Thus whatever garbage or old block we end up pointing at complains when we mount the file system later and try to replay the log. Fix this by copying the log's root item into a local root item copy. Then once we're safely under the log_root_tree->log_mutex we update the root item in the log_root_tree. This way we do not modify the log_root_tree while we're committing it, fixing the problem. CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Chris Mason <clm@fb.com> Reviewed-by: Filipe Manana <fdmanana@suse.com> Signed-off-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: David Sterba <dsterba@suse.com>
| * | | | Btrfs: fix memory leak due to concurrent append writes with fiemapFilipe Manana2019-10-011-1/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When we have a buffered write that starts at an offset greater than or equals to the file's size happening concurrently with a full ranged fiemap, we can end up leaking an extent state structure. Suppose we have a file with a size of 1Mb, and before the buffered write and fiemap are performed, it has a single extent state in its io tree representing the range from 0 to 1Mb, with the EXTENT_DELALLOC bit set. The following sequence diagram shows how the memory leak happens if a fiemap a buffered write, starting at offset 1Mb and with a length of 4Kb, are performed concurrently. CPU 1 CPU 2 extent_fiemap() --> it's a full ranged fiemap range from 0 to LLONG_MAX - 1 (9223372036854775807) --> locks range in the inode's io tree --> after this we have 2 extent states in the io tree: --> 1 for range [0, 1Mb[ with the bits EXTENT_LOCKED and EXTENT_DELALLOC_BITS set --> 1 for the range [1Mb, LLONG_MAX[ with the EXTENT_LOCKED bit set --> start buffered write at offset 1Mb with a length of 4Kb btrfs_file_write_iter() btrfs_buffered_write() --> cached_state is NULL lock_and_cleanup_extent_if_need() --> returns 0 and does not lock range because it starts at current i_size / eof --> cached_state remains NULL btrfs_dirty_pages() btrfs_set_extent_delalloc() (...) __set_extent_bit() --> splits extent state for range [1Mb, LLONG_MAX[ and now we have 2 extent states: --> one for the range [1Mb, 1Mb + 4Kb[ with EXTENT_LOCKED set --> another one for the range [1Mb + 4Kb, LLONG_MAX[ with EXTENT_LOCKED set as well --> sets EXTENT_DELALLOC on the extent state for the range [1Mb, 1Mb + 4Kb[ --> caches extent state [1Mb, 1Mb + 4Kb[ into @cached_state because it has the bit EXTENT_LOCKED set --> btrfs_buffered_write() ends up with a non-NULL cached_state and never calls anything to release its reference on it, resulting in a memory leak Fix this by calling free_extent_state() on cached_state if the range was not locked by lock_and_cleanup_extent_if_need(). The same issue can happen if anything else other than fiemap locks a range that covers eof and beyond. This could be triggered, sporadically, by test case generic/561 from the fstests suite, which makes duperemove run concurrently with fsstress, and duperemove does plenty of calls to fiemap. When CONFIG_BTRFS_DEBUG is set the leak is reported in dmesg/syslog when removing the btrfs module with a message like the following: [77100.039461] BTRFS: state leak: start 6574080 end 6582271 state 16402 in tree 0 refs 1 Otherwise (CONFIG_BTRFS_DEBUG not set) detectable with kmemleak. CC: stable@vger.kernel.org # 4.16+ Reviewed-by: Josef Bacik <josef@toxicpanda.com> Signed-off-by: Filipe Manana <fdmanana@suse.com> Reviewed-by: David Sterba <dsterba@suse.com> Signed-off-by: David Sterba <dsterba@suse.com>
* | | | | Merge branch 'work.dcache' of ↵Linus Torvalds2019-10-101-66/+71
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull dcache_readdir() fixes from Al Viro: "The couple of patches you'd been OK with; no hlist conversion yet, and cursors are still in the list of children" [ Al is referring to future work to avoid some nasty O(n**2) behavior with the readdir cursors when you have lots of concurrent readdirs. This is just a fix for a race with a trivial cleanup - Linus ] * 'work.dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: libfs: take cursors out of list when moving past the end of directory Fix the locking in dcache_readdir() and friends
| * | | | | libfs: take cursors out of list when moving past the end of directoryAl Viro2019-10-091-24/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | that eliminates the last place where we accessed the tail of ->d_subdirs Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
| * | | | | Fix the locking in dcache_readdir() and friendsAl Viro2019-09-221-65/+69
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are two problems in dcache_readdir() - one is that lockless traversal of the list needs non-trivial cooperation of d_alloc() (at least a switch to list_add_rcu(), and probably more than just that) and another is that it assumes that no removal will happen without the directory locked exclusive. Said assumption had always been there, never had been stated explicitly and is violated by several places in the kernel (devpts and selinuxfs). * replacement of next_positive() with different calling conventions: it returns struct list_head * instead of struct dentry *; the latter is passed in and out by reference, grabbing the result and dropping the original value. * scan is under ->d_lock. If we run out of timeslice, cursor is moved after the last position we'd reached and we reschedule; then the scan continues from that place. To avoid livelocks between multiple lseek() (with cursors getting moved past each other, never reaching the real entries) we always skip the cursors, need_resched() or not. * returned list_head * is either ->d_child of dentry we'd found or ->d_subdirs of parent (if we got to the end of the list). * dcache_readdir() and dcache_dir_lseek() switched to new helper. dcache_readdir() always holds a reference to dentry passed to dir_emit() now. Cursor is moved to just before the entry where dir_emit() has failed or into the very end of the list, if we'd run out. * move_cursor() eliminated - it had sucky calling conventions and after fixing that it became simply list_move() (in lseek and scan_positives) or list_move_tail() (in readdir). All operations with the list are under ->d_lock now, and we do not depend upon having all file removals done with parent locked exclusive anymore. Cc: stable@vger.kernel.org Reported-by: "zhengbin (A)" <zhengbin13@huawei.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | | Merge branch 'work.mount3' of ↵Linus Torvalds2019-10-101-1/+4
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull mount fixes from Al Viro: "A couple of regressions from the mount series" * 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: add missing blkdev_put() in get_tree_bdev() shmem: fix LSM options parsing
| * | | | | | vfs: add missing blkdev_put() in get_tree_bdev()Ian Kent2019-10-091-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Is there are a couple of missing blkdev_put() in get_tree_bdev()? Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | | | | Merge branch 'akpm' (patches from Andrew)Linus Torvalds2019-10-074-38/+54
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge misc fixes from Andrew Morton: "The usual shower of hotfixes. Chris's memcg patches aren't actually fixes - they're mature but a few niggling review issues were late to arrive. The ocfs2 fixes are quite old - those took some time to get reviewer attention. Subsystems affected by this patch series: ocfs2, hotfixes, mm/memcg, mm/slab-generic" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two) mm, sl[ou]b: improve memory accounting mm, memcg: make scan aggression always exclude protection mm, memcg: make memory.emin the baseline for utilisation determination mm, memcg: proportional memory.{low,min} reclaim mm/vmpressure.c: fix a signedness bug in vmpressure_register_event() mm/page_alloc.c: fix a crash in free_pages_prepare() mm/z3fold.c: claim page in the beginning of free kernel/sysctl.c: do not override max_threads provided by userspace memcg: only record foreign writebacks with dirty pages when memcg is not disabled mm: fix -Wmissing-prototypes warnings writeback: fix use-after-free in finish_writeback_work() mm/memremap: drop unused SECTION_SIZE and SECTION_MASK panic: ensure preemption is disabled during panic() fs: ocfs2: fix a possible null-pointer dereference in ocfs2_info_scan_inode_alloc() fs: ocfs2: fix a possible null-pointer dereference in ocfs2_write_end_nolock() fs: ocfs2: fix possible null-pointer dereferences in ocfs2_xa_prepare_entry() ocfs2: clear zero in unaligned direct IO
| * | | | | | | writeback: fix use-after-free in finish_writeback_work()Tejun Heo2019-10-071-2/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | finish_writeback_work() reads @done->waitq after decrementing @done->cnt. However, once @done->cnt reaches zero, @done may be freed (from stack) at any moment and @done->waitq can contain something unrelated by the time finish_writeback_work() tries to read it. This led to the following crash. "BUG: kernel NULL pointer dereference, address: 0000000000000002" #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] SMP DEBUG_PAGEALLOC CPU: 40 PID: 555153 Comm: kworker/u98:50 Kdump: loaded Not tainted ... Workqueue: writeback wb_workfn (flush-btrfs-1) RIP: 0010:_raw_spin_lock_irqsave+0x10/0x30 Code: 48 89 d8 5b c3 e8 50 db 6b ff eb f4 0f 1f 40 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 53 9c 5b fa 31 c0 ba 01 00 00 00 <f0> 0f b1 17 75 05 48 89 d8 5b c3 89 c6 e8 fe ca 6b ff eb f2 66 90 RSP: 0018:ffffc90049b27d98 EFLAGS: 00010046 RAX: 0000000000000000 RBX: 0000000000000246 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 0000000000000003 RDI: 0000000000000002 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000001 R10: ffff889fff407600 R11: ffff88ba9395d740 R12: 000000000000e300 R13: 0000000000000003 R14: 0000000000000000 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88bfdfa00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000002 CR3: 0000000002409005 CR4: 00000000001606e0 Call Trace: __wake_up_common_lock+0x63/0xc0 wb_workfn+0xd2/0x3e0 process_one_work+0x1f5/0x3f0 worker_thread+0x2d/0x3d0 kthread+0x111/0x130 ret_from_fork+0x1f/0x30 Fix it by reading and caching @done->waitq before decrementing @done->cnt. Link: http://lkml.kernel.org/r/20190924010631.GH2233839@devbig004.ftw2.facebook.com Fixes: 5b9cce4c7eb069 ("writeback: Generalize and expose wb_completion") Signed-off-by: Tejun Heo <tj@kernel.org> Debugged-by: Chris Mason <clm@fb.com> Reviewed-by: Jens Axboe <axboe@kernel.dk> Cc: Jan Kara <jack@suse.cz> Cc: <stable@vger.kernel.org> [5.2+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | fs: ocfs2: fix a possible null-pointer dereference in ↵Jia-Ju Bai2019-10-071-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | ocfs2_info_scan_inode_alloc() In ocfs2_info_scan_inode_alloc(), there is an if statement on line 283 to check whether inode_alloc is NULL: if (inode_alloc) When inode_alloc is NULL, it is used on line 287: ocfs2_inode_lock(inode_alloc, &bh, 0); ocfs2_inode_lock_full_nested(inode, ...) struct ocfs2_super *osb = OCFS2_SB(inode->i_sb); Thus, a possible null-pointer dereference may occur. To fix this bug, inode_alloc is checked on line 286. This bug is found by a static analysis tool STCheck written by us. Link: http://lkml.kernel.org/r/20190726033717.32359-1-baijiaju1990@gmail.com Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | fs: ocfs2: fix a possible null-pointer dereference in ocfs2_write_end_nolock()Jia-Ju Bai2019-10-071-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In ocfs2_write_end_nolock(), there are an if statement on lines 1976, 2047 and 2058, to check whether handle is NULL: if (handle) When handle is NULL, it is used on line 2045: ocfs2_update_inode_fsync_trans(handle, inode, 1); oi->i_sync_tid = handle->h_transaction->t_tid; Thus, a possible null-pointer dereference may occur. To fix this bug, handle is checked before calling ocfs2_update_inode_fsync_trans(). This bug is found by a static analysis tool STCheck written by us. Link: http://lkml.kernel.org/r/20190726033705.32307-1-baijiaju1990@gmail.com Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | fs: ocfs2: fix possible null-pointer dereferences in ocfs2_xa_prepare_entry()Jia-Ju Bai2019-10-071-33/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In ocfs2_xa_prepare_entry(), there is an if statement on line 2136 to check whether loc->xl_entry is NULL: if (loc->xl_entry) When loc->xl_entry is NULL, it is used on line 2158: ocfs2_xa_add_entry(loc, name_hash); loc->xl_entry->xe_name_hash = cpu_to_le32(name_hash); loc->xl_entry->xe_name_offset = cpu_to_le16(loc->xl_size); and line 2164: ocfs2_xa_add_namevalue(loc, xi); loc->xl_entry->xe_value_size = cpu_to_le64(xi->xi_value_len); loc->xl_entry->xe_name_len = xi->xi_name_len; Thus, possible null-pointer dereferences may occur. To fix these bugs, if loc-xl_entry is NULL, ocfs2_xa_prepare_entry() abnormally returns with -EINVAL. These bugs are found by a static analysis tool STCheck written by us. [akpm@linux-foundation.org: remove now-unused ocfs2_xa_add_entry()] Link: http://lkml.kernel.org/r/20190726101447.9153-1-baijiaju1990@gmail.com Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| * | | | | | | ocfs2: clear zero in unaligned direct IOJia Guo2019-10-071-1/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Unused portion of a part-written fs-block-sized block is not set to zero in unaligned append direct write.This can lead to serious data inconsistencies. Ocfs2 manage disk with cluster size(for example, 1M), part-written in one cluster will change the cluster state from UN-WRITTEN to WRITTEN, VFS(function dio_zero_block) doesn't do the cleaning because bh's state is not set to NEW in function ocfs2_dio_wr_get_block when we write a WRITTEN cluster. For example, the cluster size is 1M, file size is 8k and we direct write from 14k to 15k, then 12k~14k and 15k~16k will contain dirty data. We have to deal with two cases: 1.The starting position of direct write is outside the file. 2.The starting position of direct write is located in the file. We need set bh's state to NEW in the first case. In the second case, we need mapped twice because bh's state of area out file should be set to NEW while area in file not. [akpm@linux-foundation.org: coding style fixes] Link: http://lkml.kernel.org/r/5292e287-8f1a-fd4a-1a14-661e555e0bed@huawei.com Signed-off-by: Jia Guo <guojia12@huawei.com> Reviewed-by: Yiwen Jiang <jiangyiwen@huawei.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Joseph Qi <joseph.qi@huawei.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | | | | | | | uaccess: implement a proper unsafe_copy_to_user() and switch filldir over to itLinus Torvalds2019-10-071-42/+2
| |_|_|_|/ / / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In commit 9f79b78ef744 ("Convert filldir[64]() from __put_user() to unsafe_put_user()") I made filldir() use unsafe_put_user(), which improves code generation on x86 enormously. But because we didn't have a "unsafe_copy_to_user()", the dirent name copy was also done by hand with unsafe_put_user() in a loop, and it turns out that a lot of other architectures didn't like that, because unlike x86, they have various alignment issues. Most non-x86 architectures trap and fix it up, and some (like xtensa) will just fail unaligned put_user() accesses unconditionally. Which makes that "copy using put_user() in a loop" not work for them at all. I could make that code do explicit alignment etc, but the architectures that don't like unaligned accesses also don't really use the fancy "user_access_begin/end()" model, so they might just use the regular old __copy_to_user() interface. So this commit takes that looping implementation, turns it into the x86 version of "unsafe_copy_to_user()", and makes other architectures implement the unsafe copy version as __copy_to_user() (the same way they do for the other unsafe_xyz() accessor functions). Note that it only does this for the copying _to_ user space, and we still don't have a unsafe version of copy_from_user(). That's partly because we have no current users of it, but also partly because the copy_from_user() case is slightly different and cannot efficiently be implemented in terms of a unsafe_get_user() loop (because gcc can't do asm goto with outputs). It would be trivial to do this using "rep movsb", which would work really nicely on newer x86 cores, but really badly on some older ones. Al Viro is looking at cleaning up all our user copy routines to make this all a non-issue, but for now we have this simple-but-stupid version for x86 that works fine for the dirent name copy case because those names are short strings and we simply don't need anything fancier. Fixes: 9f79b78ef744 ("Convert filldir[64]() from __put_user() to unsafe_put_user()") Reported-by: Guenter Roeck <linux@roeck-us.net> Reported-and-tested-by: Tony Luck <tony.luck@intel.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Max Filippov <jcmvbkbc@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-02 21:17:59 +0000