kernel/linux.git/include, branch v4.4.171

sunrpc: use-after-free in svc_process_common()

2019-01-16T21:16:12+00:00

commit d4b09acf924b84bae77cad090a9d108e70b43643 upstream. if node have NFSv41+ mounts inside several net namespaces it can lead to use-after-free in svc_process_common() svc_process_common() /* Setup reply header */ rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp); <<< HERE svc_process_common() can use incorrect rqstp->rq_xprt, its caller function bc_svc_process() takes it from serv->sv_bc_xprt. The problem is that serv is global structure but sv_bc_xprt is assigned per-netnamespace. According to Trond, the whole "let's set up rqstp->rq_xprt for the back channel" is nothing but a giant hack in order to work around the fact that svc_process_common() uses it to find the xpt_ops, and perform a couple of (meaningless for the back channel) tests of xpt_flags. All we really need in svc_process_common() is to be able to run rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr() Bruce J Fields points that this xpo_prep_reply_hdr() call is an awfully roundabout way just to do "svc_putnl(resv, 0);" in the tcp case. This patch does not initialiuze rqstp->rq_xprt in bc_svc_process(), now it calls svc_process_common() with rqstp->rq_xprt = NULL. To adjust reply header svc_process_common() just check rqstp->rq_prot and calls svc_tcp_prep_reply_hdr() for tcp case. To handle rqstp->rq_xprt = NULL case in functions called from svc_process_common() patch intruduces net namespace pointer svc_rqst->rq_bc_net and adjust SVC_NET() definition. Some other function was also adopted to properly handle described case. Signed-off-by: Vasily Averin Cc: stable@vger.kernel.org Fixes: 23c20ecd4475 ("NFS: callback up - users counting cleanup") Signed-off-by: J. Bruce Fields v2: - added lost extern svc_tcp_prep_reply_hdr() - dropped trace_svc_process() changes - context fixes in svc_process_common() Signed-off-by: Vasily Averin Signed-off-by: Greg Kroah-Hartman

Input: restore EV_ABS ABS_RESERVED

2019-01-13T09:05:31+00:00

[ Upstream commit c201e3808e0e4be9b98d192802085a9f491bd80c ] ABS_RESERVED was added in d9ca1c990a7 and accidentally removed as part of ffe0e7cf290f5c9 when the high-resolution scrolling code was removed. Signed-off-by: Peter Hutterer Reviewed-by: Martin Kepplinger Acked-by: Benjamin Tissoires Acked-by: Dmitry Torokhov Signed-off-by: Benjamin Tissoires Signed-off-by: Sasha Levin

ext4: force inode writes when nfsd calls commit_metadata()

2019-01-13T09:05:30+00:00

commit fde872682e175743e0c3ef939c89e3c6008a1529 upstream. Some time back, nfsd switched from calling vfs_fsync() to using a new commit_metadata() hook in export_operations(). If the file system did not provide a commit_metadata() hook, it fell back to using sync_inode_metadata(). Unfortunately doesn't work on all file systems. In particular, it doesn't work on ext4 due to how the inode gets journalled --- the VFS writeback code will not always call ext4_write_inode(). So we need to provide our own ext4_nfs_commit_metdata() method which calls ext4_write_inode() directly. Google-Bug-Id: 121195940 Signed-off-by: Theodore Ts'o Cc: stable@kernel.org Signed-off-by: Greg Kroah-Hartman

sock: Make sock->sk_stamp thread-safe

2019-01-13T09:05:28+00:00

[ Upstream commit 3a0ed3e9619738067214871e9cb826fa23b2ddb9 ] Al Viro mentioned (Message-ID <20170626041334.GZ10672@ZenIV.linux.org.uk>) that there is probably a race condition lurking in accesses of sk_stamp on 32-bit machines. sock->sk_stamp is of type ktime_t which is always an s64. On a 32 bit architecture, we might run into situations of unsafe access as the access to the field becomes non atomic. Use seqlocks for synchronization. This allows us to avoid using spinlocks for readers as readers do not need mutual exclusion. Another approach to solve this is to require sk_lock for all modifications of the timestamps. The current approach allows for timestamps to have their own lock: sk_stamp_lock. This allows for the patch to not compete with already existing critical sections, and side effects are limited to the paths in the patch. The addition of the new field maintains the data locality optimizations from commit 9115e8cd2a0c ("net: reorganize struct sock for better data locality") Note that all the instances of the sk_stamp accesses are either through the ioctl or the syscall recvmsg. Signed-off-by: Deepa Dinamani Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

gro_cell: add napi_disable in gro_cells_destroy

2019-01-13T09:05:28+00:00

[ Upstream commit 8e1da73acded4751a93d4166458a7e640f37d26c ] Add napi_disable routine in gro_cells_destroy since starting from commit c42858eaf492 ("gro_cells: remove spinlock protecting receive queues") gro_cell_poll and gro_cells_destroy can run concurrently on napi_skbs list producing a kernel Oops if the tunnel interface is removed while gro_cell_poll is running. The following Oops has been triggered removing a vxlan device while the interface is receiving traffic [ 5628.948853] BUG: unable to handle kernel NULL pointer dereference at 0000000000000008 [ 5628.949981] PGD 0 P4D 0 [ 5628.950308] Oops: 0002 [#1] SMP PTI [ 5628.950748] CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 4.20.0-rc6+ #41 [ 5628.952940] RIP: 0010:gro_cell_poll+0x49/0x80 [ 5628.955615] RSP: 0018:ffffc9000004fdd8 EFLAGS: 00010202 [ 5628.956250] RAX: 0000000000000000 RBX: ffffe8ffffc08150 RCX: 0000000000000000 [ 5628.957102] RDX: 0000000000000000 RSI: ffff88802356bf00 RDI: ffffe8ffffc08150 [ 5628.957940] RBP: 0000000000000026 R08: 0000000000000000 R09: 0000000000000000 [ 5628.958803] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000040 [ 5628.959661] R13: ffffe8ffffc08100 R14: 0000000000000000 R15: 0000000000000040 [ 5628.960682] FS: 0000000000000000(0000) GS:ffff88803ea00000(0000) knlGS:0000000000000000 [ 5628.961616] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 5628.962359] CR2: 0000000000000008 CR3: 000000000221c000 CR4: 00000000000006b0 [ 5628.963188] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 5628.964034] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 5628.964871] Call Trace: [ 5628.965179] net_rx_action+0xf0/0x380 [ 5628.965637] __do_softirq+0xc7/0x431 [ 5628.966510] run_ksoftirqd+0x24/0x30 [ 5628.966957] smpboot_thread_fn+0xc5/0x160 [ 5628.967436] kthread+0x113/0x130 [ 5628.968283] ret_from_fork+0x3a/0x50 [ 5628.968721] Modules linked in: [ 5628.969099] CR2: 0000000000000008 [ 5628.969510] ---[ end trace 9d9dedc7181661fe ]--- [ 5628.970073] RIP: 0010:gro_cell_poll+0x49/0x80 [ 5628.972965] RSP: 0018:ffffc9000004fdd8 EFLAGS: 00010202 [ 5628.973611] RAX: 0000000000000000 RBX: ffffe8ffffc08150 RCX: 0000000000000000 [ 5628.974504] RDX: 0000000000000000 RSI: ffff88802356bf00 RDI: ffffe8ffffc08150 [ 5628.975462] RBP: 0000000000000026 R08: 0000000000000000 R09: 0000000000000000 [ 5628.976413] R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000040 [ 5628.977375] R13: ffffe8ffffc08100 R14: 0000000000000000 R15: 0000000000000040 [ 5628.978296] FS: 0000000000000000(0000) GS:ffff88803ea00000(0000) knlGS:0000000000000000 [ 5628.979327] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 5628.980044] CR2: 0000000000000008 CR3: 000000000221c000 CR4: 00000000000006b0 [ 5628.980929] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 5628.981736] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [ 5628.982409] Kernel panic - not syncing: Fatal exception in interrupt [ 5628.983307] Kernel Offset: disabled Fixes: c42858eaf492 ("gro_cells: remove spinlock protecting receive queues") Signed-off-by: Lorenzo Bianconi Acked-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

proc: do not access cmdline nor environ from file-backed areas

2018-12-17T20:55:17+00:00

commit 7f7ccc2ccc2e70c6054685f5e3522efa81556830 upstream. proc_pid_cmdline_read() and environ_read() directly access the target process' VM to retrieve the command line and environment. If this process remaps these areas onto a file via mmap(), the requesting process may experience various issues such as extra delays if the underlying device is slow to respond. Let's simply refuse to access file-backed areas in these functions. For this we add a new FOLL_ANON gup flag that is passed to all calls to access_remote_vm(). The code already takes care of such failures (including unmapped areas). Accesses via /proc/pid/mem were not changed though. This was assigned CVE-2018-1120. Note for stable backports: the patch may apply to kernels prior to 4.11 but silently miss one location; it must be checked that no call to access_remote_vm() keeps zero as the last argument. Reported-by: Qualys Security Advisory Cc: Linus Torvalds Cc: Andy Lutomirski Cc: Oleg Nesterov Signed-off-by: Willy Tarreau Signed-off-by: Linus Torvalds [bwh: Backported to 4.4: - Update the extra call to access_remote_vm() from proc_pid_cmdline_read() - Adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

mm: replace access_remote_vm() write parameter with gup_flags

2018-12-17T20:55:17+00:00

commit 6347e8d5bcce33fc36e651901efefbe2c93a43ef upstream. This removes the 'write' argument from access_remote_vm() and replaces it with 'gup_flags' as use of this function previously silently implied FOLL_FORCE, whereas after this patch callers explicitly pass this flag. We make this explicit as use of FOLL_FORCE can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes Acked-by: Michal Hocko Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

mm: replace get_user_pages() write/force parameters with gup_flags

2018-12-17T20:55:16+00:00

commit 768ae309a96103ed02eb1e111e838c87854d8b51 upstream. This removes the 'write' and 'force' from get_user_pages() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes Acked-by: Christian König Acked-by: Jesper Nilsson Acked-by: Michal Hocko Reviewed-by: Jan Kara Signed-off-by: Linus Torvalds [bwh: Backported to 4.4: - Drop changes in rapidio, vchiq, goldfish - Keep the "write" variable in amdgpu_ttm_tt_pin_userptr() as it's still needed - Also update calls from various other places that now use get_user_pages_remote() upstream, which were updated there by commit 9beae1ea8930 "mm: replace get_user_pages_remote() write/force ..." - Also update calls from hfi1 and ipath - Adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

mm: replace get_vaddr_frames() write/force parameters with gup_flags

2018-12-17T20:55:16+00:00

commit 7f23b3504a0df63b724180262c5f3f117f21bcae upstream. This removes the 'write' and 'force' from get_vaddr_frames() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes Acked-by: Michal Hocko Reviewed-by: Jan Kara Signed-off-by: Linus Torvalds Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

mm: replace get_user_pages_locked() write/force parameters with gup_flags

2018-12-17T20:55:16+00:00

commit 3b913179c3fa89dd0e304193fa0c746fc0481447 upstream. This removes the 'write' and 'force' use from get_user_pages_locked() and replaces them with 'gup_flags' to make the use of FOLL_FORCE explicit in callers as use of this flag can result in surprising behaviour (and hence bugs) within the mm subsystem. Signed-off-by: Lorenzo Stoakes Acked-by: Michal Hocko Reviewed-by: Jan Kara Signed-off-by: Linus Torvalds [bwh: Backported to 4.4: adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman