209aa23083
Calling pnfs_put_lset on an IS_ERR pointer results in a NULL pointer dereference like the one below. At the same time the check of retvalue of filelayout_check_deviceid() sets lseg to error, but does not free it before that. [ 3000.636161] BUG: unable to handle kernel NULL pointer dereference at 000000000000003c [ 3000.636970] IP: pnfs_put_lseg+0x29/0x100 [nfsv4] [ 3000.637420] PGD 4f23b067 [ 3000.637421] PUD 4a0f4067 [ 3000.637679] PMD 0 [ 3000.637937] [ 3000.638287] Oops: 0000 [#1] SMP [ 3000.638591] Modules linked in: nfs_layout_nfsv41_files nfsv3 nfnetlink_queue nfnetlink_log nfnetlink bluetooth rfkill rpcsec_gss_krb5 nfsv4 nfs fscache binfmt_misc arc4 md4 nls_utf8 cifs ccm dns_resolver rpcrdma ib_isert iscsi_target_mod ib_iser rdma_cm iw_cm libiscsi scsi_transport_iscsi ib_srpt target_core_mod ib_srp scsi_transport_srp ib_ipoib ib_ucm ib_uverbs ib_umad ib_cm ib_core nls_koi8_u nls_cp932 ts_kmp nf_conntrack_ipv4 nf_defrag_ipv4 nf_conntrack crct10dif_pclmul crc32_pclmul ghash_clmulni_intel pcspkr virtio_balloon ppdev virtio_rng parport_pc i2c_piix4 parport acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc xfs libcrc32c ata_generic pata_acpi virtio_blk virtio_net cirrus drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops crc32c_intel ata_piix ttm libata drm serio_raw [ 3000.645245] i2c_core virtio_pci virtio_ring virtio floppy dm_mirror dm_region_hash dm_log dm_mod [last unloaded: xt_u32] [ 3000.646360] CPU: 1 PID: 26402 Comm: date Not tainted 4.11.0-rc7.1.el7.test.x86_64 #1 [ 3000.647092] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 3000.647638] task: ffff8800415ada00 task.stack: ffffc90000ff0000 [ 3000.648207] RIP: 0010:pnfs_put_lseg+0x29/0x100 [nfsv4] [ 3000.648696] RSP: 0018:ffffc90000ff39b8 EFLAGS: 00010246 [ 3000.649193] RAX: 0000000000000000 RBX: fffffffffffffff4 RCX: 00000000000d43be [ 3000.649859] RDX: 00000000000d43bd RSI: 0000000000000000 RDI: fffffffffffffff4 [ 3000.650530] RBP: ffffc90000ff39d8 R08: 000000000001e320 R09: ffffffffa05c35ce [ 3000.651203] R10: ffff88007fd1e320 R11: ffffea0001283d80 R12: 0000000001400040 [ 3000.651875] R13: ffff88004f77d9f0 R14: ffffc90000ff3cd8 R15: ffff8800417ade00 [ 3000.652546] FS: 00007fac4d5cd740(0000) GS:ffff88007fd00000(0000) knlGS:0000000000000000 [ 3000.653304] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 3000.653849] CR2: 000000000000003c CR3: 000000004f080000 CR4: 00000000000406e0 [ 3000.654527] Call Trace: [ 3000.654771] fl_pnfs_update_layout.constprop.20+0x10c/0x150 [nfs_layout_nfsv41_files] [ 3000.655505] filelayout_pg_init_write+0x21d/0x270 [nfs_layout_nfsv41_files] [ 3000.656195] __nfs_pageio_add_request+0x11c/0x490 [nfs] [ 3000.656698] nfs_pageio_add_request+0xac/0x260 [nfs] [ 3000.657180] nfs_do_writepage+0x109/0x2e0 [nfs] [ 3000.657616] nfs_writepages_callback+0x16/0x30 [nfs] [ 3000.658096] write_cache_pages+0x26f/0x510 [ 3000.658495] ? nfs_do_writepage+0x2e0/0x2e0 [nfs] [ 3000.658946] ? _raw_spin_unlock_bh+0x1e/0x20 [ 3000.659357] ? wb_wakeup_delayed+0x5f/0x70 [ 3000.659748] ? __mark_inode_dirty+0x2eb/0x360 [ 3000.660170] nfs_writepages+0x84/0xd0 [nfs] [ 3000.660575] ? nfs_updatepage+0x571/0xb70 [nfs] [ 3000.661012] do_writepages+0x1e/0x30 [ 3000.661358] __filemap_fdatawrite_range+0xc6/0x100 [ 3000.661819] filemap_write_and_wait_range+0x41/0x90 [ 3000.662292] nfs_file_fsync+0x34/0x1f0 [nfs] [ 3000.662704] vfs_fsync_range+0x3d/0xb0 [ 3000.663065] vfs_fsync+0x1c/0x20 [ 3000.663385] nfs4_file_flush+0x57/0x80 [nfsv4] [ 3000.663813] filp_close+0x2f/0x70 [ 3000.664132] __close_fd+0x9a/0xc0 [ 3000.664453] SyS_close+0x23/0x50 [ 3000.664785] do_syscall_64+0x67/0x180 [ 3000.665162] entry_SYSCALL64_slow_path+0x25/0x25 [ 3000.665600] RIP: 0033:0x7fac4d0e1e90 [ 3000.665946] RSP: 002b:00007ffd54e90c88 EFLAGS: 00000246 ORIG_RAX: 0000000000000003 [ 3000.666679] RAX: ffffffffffffffda RBX: 00007fac4d3b5400 RCX: 00007fac4d0e1e90 [ 3000.667349] RDX: 0000000000000000 RSI: 00007fac4d5d9000 RDI: 0000000000000001 [ 3000.668031] RBP: 0000000000000000 R08: 00007fac4d3b6a00 R09: 00007fac4d5cd740 [ 3000.668709] R10: 00007ffd54e909e0 R11: 0000000000000246 R12: 0000000000000000 [ 3000.669385] R13: 00007fac4d3b5e80 R14: 0000000000000000 R15: 0000000000000000 [ 3000.670061] Code: 00 00 66 66 66 66 90 55 48 85 ff 48 89 e5 41 56 41 55 41 54 53 48 89 fb 0f 84 97 00 00 00 f6 05 16 8f bc ff 10 0f 85 a6 00 00 00 <4c> 8b 63 48 48 8d 7b 38 49 8b 84 24 90 00 00 00 4c 8d a8 88 00 [ 3000.671831] RIP: pnfs_put_lseg+0x29/0x100 [nfsv4] RSP: ffffc90000ff39b8 [ 3000.672462] CR2: 000000000000003c Signed-off-by: Artem Savkov <asavkov@redhat.com> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.