commit a8c90ef62281db933118aa84489eb0e1e9cc347c Author: Greg Kroah-Hartman Date: Thu Apr 27 09:11:26 2017 +0200 Linux 4.9.25 commit c36eaa6ca346dc8d45e9125af62db75625b42a6f Author: Dan Williams Date: Fri Apr 7 16:42:08 2017 -0700 device-dax: switch to srcu, fix rcu_read_lock() vs pte allocation commit 956a4cd2c957acf638ff29951aabaa9d8e92bbc2 upstream. The following warning triggers with a new unit test that stresses the device-dax interface. =============================== [ ERR: suspicious RCU usage. ] 4.11.0-rc4+ #1049 Tainted: G O ------------------------------- ./include/linux/rcupdate.h:521 Illegal context switch in RCU read-side critical section! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 0 2 locks held by fio/9070: #0: (&mm->mmap_sem){++++++}, at: [] __do_page_fault+0x167/0x4f0 #1: (rcu_read_lock){......}, at: [] dax_dev_huge_fault+0x32/0x620 [dax] Call Trace: dump_stack+0x86/0xc3 lockdep_rcu_suspicious+0xd7/0x110 ___might_sleep+0xac/0x250 __might_sleep+0x4a/0x80 __alloc_pages_nodemask+0x23a/0x360 alloc_pages_current+0xa1/0x1f0 pte_alloc_one+0x17/0x80 __pte_alloc+0x1e/0x120 __get_locked_pte+0x1bf/0x1d0 insert_pfn.isra.70+0x3a/0x100 ? lookup_memtype+0xa6/0xd0 vm_insert_mixed+0x64/0x90 dax_dev_huge_fault+0x520/0x620 [dax] ? dax_dev_huge_fault+0x32/0x620 [dax] dax_dev_fault+0x10/0x20 [dax] __do_fault+0x1e/0x140 __handle_mm_fault+0x9af/0x10d0 handle_mm_fault+0x16d/0x370 ? handle_mm_fault+0x47/0x370 __do_page_fault+0x28c/0x4f0 trace_do_page_fault+0x58/0x2a0 do_async_page_fault+0x1a/0xa0 async_page_fault+0x28/0x30 Inserting a page table entry may trigger an allocation while we are holding a read lock to keep the device instance alive for the duration of the fault. Use srcu for this keep-alive protection. Fixes: dee410792419 ("/dev/dax, core: file operations and dax-mmap") Signed-off-by: Dan Williams Signed-off-by: Greg Kroah-Hartman commit f8bc0881fe95496ddf3f8a16808d9860db207941 Author: Vishal Verma Date: Tue Apr 18 20:42:35 2017 +0200 x86/mce: Make the MCE notifier a blocking one commit 0dc9c639e6553e39c13b2c0d54c8a1b098cb95e2 upstream. The NFIT MCE handler callback (for handling media errors on NVDIMMs) takes a mutex to add the location of a memory error to a list. But since the notifier call chain for machine checks (x86_mce_decoder_chain) is atomic, we get a lockdep splat like: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:620 in_atomic(): 1, irqs_disabled(): 0, pid: 4, name: kworker/0:0 [..] Call Trace: dump_stack ___might_sleep __might_sleep mutex_lock_nested ? __lock_acquire nfit_handle_mce notifier_call_chain atomic_notifier_call_chain ? atomic_notifier_call_chain mce_gen_pool_process Convert the notifier to a blocking one which gets to run only in process context. Boris: remove the notifier call in atomic context in print_mce(). For now, let's print the MCE on the atomic path so that we can make sure they go out and get logged at least. Fixes: 6839a6d96f4e ("nfit: do an ARS scrub on hitting a latent media error") Reported-by: Ross Zwisler Signed-off-by: Vishal Verma Acked-by: Tony Luck Cc: Dan Williams Cc: linux-edac Cc: x86-ml Link: http://lkml.kernel.org/r/20170411224457.24777-1-vishal.l.verma@intel.com Signed-off-by: Borislav Petkov Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman commit 6966a6579e1bc7b3486bed395e7d6875912a9a9b Author: Yazen Ghannam Date: Thu Mar 30 13:17:14 2017 +0200 x86/mce/AMD: Give a name to MCA bank 3 when accessed with legacy MSRs commit 29f72ce3e4d18066ec75c79c857bee0618a3504b upstream. MCA bank 3 is reserved on systems pre-Fam17h, so it didn't have a name. However, MCA bank 3 is defined on Fam17h systems and can be accessed using legacy MSRs. Without a name we get a stack trace on Fam17h systems when trying to register sysfs files for bank 3 on kernels that don't recognize Scalable MCA. Call MCA bank 3 "decode_unit" since this is what it represents on Fam17h. This will allow kernels without SMCA support to see this bank on Fam17h+ and prevent the stack trace. This will not affect older systems since this bank is reserved on them, i.e. it'll be ignored. Tested on AMD Fam15h and Fam17h systems. WARNING: CPU: 26 PID: 1 at lib/kobject.c:210 kobject_add_internal kobject: (ffff88085bb256c0): attempted to be registered with empty name! ... Call Trace: kobject_add_internal kobject_add kobject_create_and_add threshold_create_device threshold_init_device Signed-off-by: Yazen Ghannam Signed-off-by: Borislav Petkov Link: http://lkml.kernel.org/r/1490102285-3659-1-git-send-email-Yazen.Ghannam@amd.com Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman commit 1bd55ab13039a0d1c004eeb7a487810138bc42c8 Author: Ravi Bangoria Date: Tue Apr 11 10:38:13 2017 +0530 powerpc/kprobe: Fix oops when kprobed on 'stdu' instruction commit 9e1ba4f27f018742a1aa95d11e35106feba08ec1 upstream. If we set a kprobe on a 'stdu' instruction on powerpc64, we see a kernel OOPS: Bad kernel stack pointer cd93c840 at c000000000009868 Oops: Bad kernel stack pointer, sig: 6 [#1] ... GPR00: c000001fcd93cb30 00000000cd93c840 c0000000015c5e00 00000000cd93c840 ... NIP [c000000000009868] resume_kernel+0x2c/0x58 LR [c000000000006208] program_check_common+0x108/0x180 On a 64-bit system when the user probes on a 'stdu' instruction, the kernel does not emulate actual store in emulate_step() because it may corrupt the exception frame. So the kernel does the actual store operation in exception return code i.e. resume_kernel(). resume_kernel() loads the saved stack pointer from memory using lwz, which only loads the low 32-bits of the address, causing the kernel crash. Fix this by loading the 64-bit value instead. Fixes: be96f63375a1 ("powerpc: Split out instruction analysis part of emulate_step()") Signed-off-by: Ravi Bangoria Reviewed-by: Naveen N. Rao Reviewed-by: Ananth N Mavinakayanahalli [mpe: Change log massage, add stable tag] Signed-off-by: Michael Ellerman Signed-off-by: Greg Kroah-Hartman commit 790b2b5a01cea4ee4284d52ea995e2af06f4f8d7 Author: Sebastian Siewior Date: Wed Feb 22 17:15:21 2017 +0100 ubi/upd: Always flush after prepared for an update commit 9cd9a21ce070be8a918ffd3381468315a7a76ba6 upstream. In commit 6afaf8a484cb ("UBI: flush wl before clearing update marker") I managed to trigger and fix a similar bug. Now here is another version of which I assumed it wouldn't matter back then but it turns out UBI has a check for it and will error out like this: |ubi0 warning: validate_vid_hdr: inconsistent used_ebs |ubi0 error: validate_vid_hdr: inconsistent VID header at PEB 592 All you need to trigger this is? "ubiupdatevol /dev/ubi0_0 file" + a powercut in the middle of the operation. ubi_start_update() sets the update-marker and puts all EBs on the erase list. After that userland can proceed to write new data while the old EB aren't erased completely. A powercut at this point is usually not that much of a tragedy. UBI won't give read access to the static volume because it has the update marker. It will most likely set the corrupted flag because it misses some EBs. So we are all good. Unless the size of the image that has been written differs from the old image in the magnitude of at least one EB. In that case UBI will find two different values for `used_ebs' and refuse to attach the image with the error message mentioned above. So in order not to get in the situation, the patch will ensure that we wait until everything is removed before it tries to write any data. The alternative would be to detect such a case and remove all EBs at the attached time after we processed the volume-table and see the update-marker set. The patch looks bigger and I doubt it is worth it since usually the write() will wait from time to time for a new EB since usually there not that many spare EB that can be used. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman commit 87cfeaa5e5a1834c2f55ade5da5a117991305269 Author: Johannes Berg Date: Thu Apr 13 14:23:49 2017 +0200 mac80211: fix MU-MIMO follow-MAC mode commit 9e478066eae41211c92a8f63cc69aafc391bd6ab upstream. There are two bugs in the follow-MAC code: * it treats the radiotap header as the 802.11 header (therefore it can't possibly work) * it doesn't verify that the skb data it accesses is actually present in the header, which is mitigated by the first point Fix this by moving all of this out into a separate function. This function copies the data it needs using skb_copy_bits() to make sure it can be accessed if it's paged, and offsets that by the possibly present vendor radiotap header. This also makes all those conditions more readable. Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman commit e0411f1eb549a7993c9821c05f1787c0bd1523b4 Author: Johannes Berg Date: Thu Apr 20 21:32:16 2017 +0200 mac80211: reject ToDS broadcast data frames commit 3018e947d7fd536d57e2b550c33e456d921fff8c upstream. AP/AP_VLAN modes don't accept any real 802.11 multicast data frames, but since they do need to accept broadcast management frames the same is currently permitted for data frames. This opens a security problem because such frames would be decrypted with the GTK, and could even contain unicast L3 frames. Since the spec says that ToDS frames must always have the BSSID as the RA (addr1), reject any other data frames. The problem was originally reported in "Predicting, Decrypting, and Abusing WPA2/802.11 Group Keys" at usenix https://www.usenix.org/conference/usenixsecurity16/technical-sessions/presentation/vanhoef and brought to my attention by Jouni. Reported-by: Jouni Malinen Signed-off-by: Johannes Berg Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman -- commit b93858556fd13c76a36a0c110450fa35eadf5671 Author: Richard Weinberger Date: Thu Mar 30 10:50:49 2017 +0200 ubifs: Fix O_TMPFILE corner case in ubifs_link() commit 32fe905c17f001c0eee13c59afddd0bf2eed509c upstream. It is perfectly fine to link a tmpfile back using linkat(). Since tmpfiles are created with a link count of 0 they appear on the orphan list, upon re-linking the inode has to be removed from the orphan list again. Ralph faced a filesystem corruption in combination with overlayfs due to this bug. Cc: Ralph Sennhauser Cc: Amir Goldstein Reported-by: Ralph Sennhauser Tested-by: Ralph Sennhauser Reported-by: Amir Goldstein Fixes: 474b93704f321 ("ubifs: Implement O_TMPFILE") Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman commit a260ff509b4d5fde2ac5f863cd3015cefbc45189 Author: Felix Fietkau Date: Mon Mar 6 10:04:25 2017 +0100 ubifs: Fix RENAME_WHITEOUT support commit c3d9fda688742c06e89aa1f0f8fd943fc11468cb upstream. Remove faulty leftover check in do_rename(), apparently introduced in a merge that combined whiteout support changes with commit f03b8ad8d386 ("fs: support RENAME_NOREPLACE for local filesystems") Fixes: f03b8ad8d386 ("fs: support RENAME_NOREPLACE for local filesystems") Fixes: 9e0a1fff8db5 ("ubifs: Implement RENAME_WHITEOUT") Signed-off-by: Felix Fietkau Signed-off-by: Richard Weinberger Signed-off-by: Greg Kroah-Hartman commit 9fc1314285360151792b6ee153c0d5181698986d Author: Haibo Chen Date: Wed Apr 19 10:53:51 2017 +0800 mmc: sdhci-esdhc-imx: increase the pad I/O drive strength for DDR50 card commit 9f327845358d3dd0d8a5a7a5436b0aa5c432e757 upstream. Currently for DDR50 card, it need tuning in default. We meet tuning fail issue for DDR50 card and some data CRC error when DDR50 sd card works. This is because the default pad I/O drive strength can't make sure DDR50 card work stable. So increase the pad I/O drive strength for DDR50 card, and use pins_100mhz. This fixes DDR50 card support for IMX since DDR50 tuning was enabled from commit 9faac7b95ea4 ("mmc: sdhci: enable tuning for DDR50") Tested-and-reported-by: Tim Harvey Signed-off-by: Haibo Chen Acked-by: Dong Aisheng Acked-by: Adrian Hunter Signed-off-by: Ulf Hansson Signed-off-by: Greg Kroah-Hartman commit 4420e5f323c408990834dddb61eb16e4a95a41e4 Author: Arnd Bergmann Date: Wed Apr 19 19:47:04 2017 +0200 ACPI / power: Avoid maybe-uninitialized warning commit fe8c470ab87d90e4b5115902dd94eced7e3305c3 upstream. gcc -O2 cannot always prove that the loop in acpi_power_get_inferred_state() is enterered at least once, so it assumes that cur_state might not get initialized: drivers/acpi/power.c: In function 'acpi_power_get_inferred_state': drivers/acpi/power.c:222:9: error: 'cur_state' may be used uninitialized in this function [-Werror=maybe-uninitialized] This sets the variable to zero at the start of the loop, to ensure that there is well-defined behavior even for an empty list. This gets rid of the warning. The warning first showed up when the -Os flag got removed in a bug fix patch in linux-4.11-rc5. I would suggest merging this addon patch on top of that bug fix to avoid introducing a new warning in the stable kernels. Fixes: 61b79e16c68d (ACPI: Fix incompatibility with mcount-based function graph tracing) Signed-off-by: Arnd Bergmann Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman commit 11ba522d7929b9c319fd31d95bbc917baad9fe6f Author: Thorsten Leemhuis Date: Tue Apr 18 11:14:28 2017 -0700 Input: elantech - add Fujitsu Lifebook E547 to force crc_enabled commit 704de489e0e3640a2ee2d0daf173e9f7375582ba upstream. Temporary got a Lifebook E547 into my hands and noticed the touchpad only works after running: echo "1" > /sys/devices/platform/i8042/serio2/crc_enabled Add it to the list of machines that need this workaround. Signed-off-by: Thorsten Leemhuis Reviewed-by: Ulrik De Bie Signed-off-by: Dmitry Torokhov Signed-off-by: Greg Kroah-Hartman commit 3d42ca46f47a4d3cd5abe465735227534c292aed Author: Christian Borntraeger Date: Sun Apr 9 22:09:38 2017 +0200 s390/mm: fix CMMA vs KSM vs others commit a8f60d1fadf7b8b54449fcc9d6b15248917478ba upstream. On heavy paging with KSM I see guest data corruption. Turns out that KSM will add pages to its tree, where the mapping return true for pte_unused (or might become as such later). KSM will unmap such pages and reinstantiate with different attributes (e.g. write protected or special, e.g. in replace_page or write_protect_page)). This uncovered a bug in our pagetable handling: We must remove the unused flag as soon as an entry becomes present again. Signed-of-by: Christian Borntraeger Signed-off-by: Martin Schwidefsky Signed-off-by: Greg Kroah-Hartman commit f79ef57911ee598e0bfb7af1ab51413429a8f9d5 Author: Germano Percossi Date: Fri Apr 7 12:29:37 2017 +0100 CIFS: remove bad_network_name flag commit a0918f1ce6a43ac980b42b300ec443c154970979 upstream. STATUS_BAD_NETWORK_NAME can be received during node failover, causing the flag to be set and making the reconnect thread always unsuccessful, thereafter. Once the only place where it is set is removed, the remaining bits are rendered moot. Removing it does not prevent "mount" from failing when a non existent share is passed. What happens when the share really ceases to exist while the share is mounted is undefined now as much as it was before. Signed-off-by: Germano Percossi Reviewed-by: Pavel Shilovsky Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman commit 0b7c970663411cbca20517f38544983ff4fd9650 Author: Sachin Prabhu Date: Sun Apr 16 20:37:24 2017 +0100 cifs: Do not send echoes before Negotiate is complete commit 62a6cfddcc0a5313e7da3e8311ba16226fe0ac10 upstream. commit 4fcd1813e640 ("Fix reconnect to not defer smb3 session reconnect long after socket reconnect") added support for Negotiate requests to be initiated by echo calls. To avoid delays in calling echo after a reconnect, I added the patch introduced by the commit b8c600120fc8 ("Call echo service immediately after socket reconnect"). This has however caused a regression with cifs shares which do not have support for echo calls to trigger Negotiate requests. On connections which need to call Negotiation, the echo calls trigger an error which triggers a reconnect which in turn triggers another echo call. This results in a loop which is only broken when an operation is performed on the cifs share. For an idle share, it can DOS a server. The patch uses the smb_operation can_echo() for cifs so that it is called only if connection has been already been setup. kernel bz: 194531 Signed-off-by: Sachin Prabhu Tested-by: Jonathan Liu Acked-by: Pavel Shilovsky Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman commit c0a602ad31ee8ee84fb1df35c2ced661b7bddd07 Author: Rabin Vincent Date: Thu Apr 20 14:37:46 2017 -0700 mm: prevent NR_ISOLATE_* stats from going negative commit fc280fe871449ead4bdbd1665fa52c7c01c64765 upstream. Commit 6afcf8ef0ca0 ("mm, compaction: fix NR_ISOLATED_* stats for pfn based migration") moved the dec_node_page_state() call (along with the page_is_file_cache() call) to after putback_lru_page(). But page_is_file_cache() can change after putback_lru_page() is called, so it should be called before putback_lru_page(), as it was before that patch, to prevent NR_ISOLATE_* stats from going negative. Without this fix, non-CONFIG_SMP kernels end up hanging in the while(too_many_isolated()) { congestion_wait() } loop in shrink_active_list() due to the negative stats. Mem-Info: active_anon:32567 inactive_anon:121 isolated_anon:1 active_file:6066 inactive_file:6639 isolated_file:4294967295 ^^^^^^^^^^ unevictable:0 dirty:115 writeback:0 unstable:0 slab_reclaimable:2086 slab_unreclaimable:3167 mapped:3398 shmem:18366 pagetables:1145 bounce:0 free:1798 free_pcp:13 free_cma:0 Fixes: 6afcf8ef0ca0 ("mm, compaction: fix NR_ISOLATED_* stats for pfn based migration") Link: http://lkml.kernel.org/r/1492683865-27549-1-git-send-email-rabin.vincent@axis.com Signed-off-by: Rabin Vincent Acked-by: Michal Hocko Cc: Ming Ling Cc: Minchan Kim Cc: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman commit d80e90712a50c8954fc3f93fa704da1a9a359077 Author: Steven Rostedt (VMware) Date: Wed Apr 19 14:29:46 2017 -0400 ring-buffer: Have ring_buffer_iter_empty() return true when empty commit 78f7a45dac2a2d2002f98a3a95f7979867868d73 upstream. I noticed that reading the snapshot file when it is empty no longer gives a status. It suppose to show the status of the snapshot buffer as well as how to allocate and use it. For example: ># cat snapshot # tracer: nop # # # * Snapshot is allocated * # # Snapshot commands: # echo 0 > snapshot : Clears and frees snapshot buffer # echo 1 > snapshot : Allocates snapshot buffer, if not already allocated. # Takes a snapshot of the main buffer. # echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free) # (Doesn't have to be '2' works with any number that # is not a '0' or '1') But instead it just showed an empty buffer: ># cat snapshot # tracer: nop # # entries-in-buffer/entries-written: 0/0 #P:4 # # _-----=> irqs-off # / _----=> need-resched # | / _---=> hardirq/softirq # || / _--=> preempt-depth # ||| / delay # TASK-PID CPU# |||| TIMESTAMP FUNCTION # | | | |||| | | What happened was that it was using the ring_buffer_iter_empty() function to see if it was empty, and if it was, it showed the status. But that function was returning false when it was empty. The reason was that the iter header page was on the reader page, and the reader page was empty, but so was the buffer itself. The check only tested to see if the iter was on the commit page, but the commit page was no longer pointing to the reader page, but as all pages were empty, the buffer is also. Fixes: 651e22f2701b ("ring-buffer: Always reset iterator to reader page") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman commit d4decac1edaadefe03bc011785cc622a64e8f19a Author: Steven Rostedt (VMware) Date: Wed Apr 19 12:07:08 2017 -0400 tracing: Allocate the snapshot buffer before enabling probe commit df62db5be2e5f070ecd1a5ece5945b590ee112e0 upstream. Currently the snapshot trigger enables the probe and then allocates the snapshot. If the probe triggers before the allocation, it could cause the snapshot to fail and turn tracing off. It's best to allocate the snapshot buffer first, and then enable the trigger. If something goes wrong in the enabling of the trigger, the snapshot buffer is still allocated, but it can also be freed by the user by writting zero into the snapshot buffer file. Also add a check of the return status of alloc_snapshot(). Fixes: 77fd5c15e3 ("tracing: Add snapshot trigger to function probes") Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman commit 174a74dbca2ddc7269c265598399c000e5b9b870 Author: Eric Biggers Date: Tue Apr 18 15:31:09 2017 +0100 KEYS: fix keyctl_set_reqkey_keyring() to not leak thread keyrings commit c9f838d104fed6f2f61d68164712e3204bf5271b upstream. This fixes CVE-2017-7472. Running the following program as an unprivileged user exhausts kernel memory by leaking thread keyrings: #include int main() { for (;;) keyctl_set_reqkey_keyring(KEY_REQKEY_DEFL_THREAD_KEYRING); } Fix it by only creating a new thread keyring if there wasn't one before. To make things more consistent, make install_thread_keyring_to_cred() and install_process_keyring_to_cred() both return 0 if the corresponding keyring is already present. Fixes: d84f4f992cbd ("CRED: Inaugurate COW credentials") Signed-off-by: Eric Biggers Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman commit b2dd90e812f3f733b55f0bf4487032e53b487665 Author: David Howells Date: Tue Apr 18 15:31:08 2017 +0100 KEYS: Change the name of the dead type to ".dead" to prevent user access commit c1644fe041ebaf6519f6809146a77c3ead9193af upstream. This fixes CVE-2017-6951. Userspace should not be able to do things with the "dead" key type as it doesn't have some of the helper functions set upon it that the kernel needs. Attempting to use it may cause the kernel to crash. Fix this by changing the name of the type to ".dead" so that it's rejected up front on userspace syscalls by key_get_type_from_user(). Though this doesn't seem to affect recent kernels, it does affect older ones, certainly those prior to: commit c06cfb08b88dfbe13be44a69ae2fdc3a7c902d81 Author: David Howells Date: Tue Sep 16 17:36:06 2014 +0100 KEYS: Remove key_type::match in favour of overriding default by match_preparse which went in before 3.18-rc1. Signed-off-by: David Howells Signed-off-by: Greg Kroah-Hartman commit a5c6e0a76817a3751f58d761aaff7c0b0c4001ff Author: David Howells Date: Tue Apr 18 15:31:07 2017 +0100 KEYS: Disallow keyrings beginning with '.' to be joined as session keyrings commit ee8f844e3c5a73b999edf733df1c529d6503ec2f upstream. This fixes CVE-2016-9604. Keyrings whose name begin with a '.' are special internal keyrings and so userspace isn't allowed to create keyrings by this name to prevent shadowing. However, the patch that added the guard didn't fix KEYCTL_JOIN_SESSION_KEYRING. Not only can that create dot-named keyrings, it can also subscribe to them as a session keyring if they grant SEARCH permission to the user. This, for example, allows a root process to set .builtin_trusted_keys as its session keyring, at which point it has full access because now the possessor permissions are added. This permits root to add extra public keys, thereby bypassing module verification. This also affects kexec and IMA. This can be tested by (as root): keyctl session .builtin_trusted_keys keyctl add user a a @s keyctl list @s which on my test box gives me: 2 keys in keyring: 180010936: ---lswrv 0 0 asymmetric: Build time autogenerated kernel key: ae3d4a31b82daa8e1a75b49dc2bba949fd992a05 801382539: --alswrv 0 0 user: a Fix this by rejecting names beginning with a '.' in the keyctl. Signed-off-by: David Howells Acked-by: Mimi Zohar cc: linux-ima-devel@lists.sourceforge.net Signed-off-by: Greg Kroah-Hartman