- 07 Jun, 2017 29 commits
-
-
Brian Foster authored
commit cb52ee33 upstream. Directory block readahead uses a complex iteration mechanism to map between high-level directory blocks and underlying physical extents. This mechanism attempts to traverse the higher-level dir blocks in a manner that handles multi-fsb directory blocks and simultaneously maintains a reference to the corresponding physical blocks. This logic doesn't handle certain (discontiguous) physical extent layouts correctly with multi-fsb directory blocks. For example, consider the case of a 4k FSB filesystem with a 2 FSB (8k) directory block size and a directory with the following extent layout: EXT: FILE-OFFSET BLOCK-RANGE AG AG-OFFSET TOTAL 0: [0..7]: 88..95 0 (88..95) 8 1: [8..15]: 80..87 0 (80..87) 8 2: [16..39]: 168..191 0 (168..191) 24 3: [40..63]: 5242952..5242975 1 (72..95) 24 Directory block 0 spans physical extents 0 and 1, dirblk 1 lies entirely within extent 2 and dirblk 2 spans extents 2 and 3. Because extent 2 is larger than the directory block size, the readahead code erroneously assumes the block is contiguous and issues a readahead based on the physical mapping of the first fsb of the dirblk. This results in read verifier failure and a spurious corruption or crc failure, depending on the filesystem format. Further, the subsequent readahead code responsible for walking through the physical table doesn't correctly advance the physical block reference for dirblk 2. Instead of advancing two physical filesystem blocks, the first iteration of the loop advances 1 block (correctly), but the subsequent iteration advances 2 more physical blocks because the next physical extent (extent 3, above) happens to cover more than dirblk 2. At this point, the higher-level directory block walking is completely off the rails of the actual physical layout of the directory for the respective mapping table. Update the contiguous dirblock logic to consider the current offset in the physical extent to avoid issuing directory readahead to unrelated blocks. Also, update the mapping table advancing code to consider the current offset within the current dirblock to avoid advancing the mapping reference too far beyond the dirblock. Signed-off-by:
Brian Foster <bfoster@redhat.com> Reviewed-by:
Darrick J. Wong <darrick.wong@oracle.com> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-
Eric Sandeen authored
commit 023cc840 upstream. Carlos had a case where "find" seemed to start spinning forever and never return. This was on a filesystem with non-default multi-fsb (8k) directory blocks, and a fragmented directory with extents like this: 0:[0,133646,2,0] 1:[2,195888,1,0] 2:[3,195890,1,0] 3:[4,195892,1,0] 4:[5,195894,1,0] 5:[6,195896,1,0] 6:[7,195898,1,0] 7:[8,195900,1,0] 8:[9,195902,1,0] 9:[10,195908,1,0] 10:[11,195910,1,0] 11:[12,195912,1,0] 12:[13,195914,1,0] ... i.e. the first extent is a contiguous 2-fsb dir block, but after that it is fragmented into 1 block extents. At the top of the readdir path, we allocate a mapping array which (for this filesystem geometry) can hold 10 extents; see the assignment to map_info->map_size. During readdir, we are therefore able to map extents 0 through 9 above into the array for readahead purposes. If we count by 2, we see that the last mapped index (9) is the first block of a 2-fsb directory block. At the end of xfs_dir2_leaf_readbuf() we have 2 loops to fill more readahead; the outer loop assumes one full dir block is processed each loop iteration, and an inner loop that ensures that this is so by advancing to the next extent until a full directory block is mapped. The problem is that this inner loop may step past the last extent in the mapping array as it tries to reach the end of the directory block. This will read garbage for the extent length, and as a result the loop control variable 'j' may become corrupted and never fail the loop conditional. The number of valid mappings we have in our array is stored in map->map_valid, so stop this inner loop based on that limit. There is an ASSERT at the top of the outer loop for this same condition, but we never made it out of the inner loop, so the ASSERT never fired. Huge appreciation for Carlos for debugging and isolating the problem. Debugged-and-analyzed-by:
Carlos Maiolino <cmaiolino@redhat.com> Signed-off-by:
Eric Sandeen <sandeen@redhat.com> Tested-by:
Bill O'Donnell <billodo@redhat.com> Reviewed-by:
-
Darrick J. Wong authored
commit be6324c0 upstream. In xfs_ioc_getbmap, we should only copy the fields of struct getbmap from userspace, or else we end up copying random stack contents into the kernel. struct getbmap is a strict subset of getbmapx, so a partial structure copy should work fine. Signed-off-by:
Christoph Hellwig <hch@lst.de> Signed-off-by:
-
Eryu Guan authored
commit 8affebe1 upstream. xfs_find_get_desired_pgoff() is used to search for offset of hole or data in page range [index, end] (both inclusive), and the max number of pages to search should be at least one, if end == index. Otherwise the only page is missed and no hole or data is found, which is not correct. When block size is smaller than page size, this can be demonstrated by preallocating a file with size smaller than page size and writing data to the last block. E.g. run this xfs_io command on a 1k block size XFS on x86_64 host. # xfs_io -fc "falloc 0 3k" -c "pwrite 2k 1k" \ -c "seek -d 0" /mnt/xfs/testfile wrote 1024/1024 bytes at offset 2048 1 KiB, 1 ops; 0.0000 sec (33.675 MiB/sec and 34482.7586 ops/sec) Whence Result DATA EOF Data at offset 2k was missed, and lseek(2) returned ENXIO. This is uncovered by generic/285 subtest 07 and 08 on ppc64 host, where pagesize is 64k. Because a recent change to generic/285 reduced the preallocated file size to smaller than 64k. Signed-off-by:
Eryu Guan <eguan@redhat.com> Reviewed-by:
Jan Kara <jack@suse.cz> Reviewed-by:
-
Jan Kara authored
commit 5375023a upstream. XFS SEEK_HOLE implementation could miss a hole in an unwritten extent as can be seen by the following command: xfs_io -c "falloc 0 256k" -c "pwrite 0 56k" -c "pwrite 128k 8k" -c "seek -h 0" file wrote 57344/57344 bytes at offset 0 56 KiB, 14 ops; 0.0000 sec (49.312 MiB/sec and 12623.9856 ops/sec) wrote 8192/8192 bytes at offset 131072 8 KiB, 2 ops; 0.0000 sec (70.383 MiB/sec and 18018.0180 ops/sec) Whence Result HOLE 139264 Where we can see that hole at offset 56k was just ignored by SEEK_HOLE implementation. The bug is in xfs_find_get_desired_pgoff() which does not properly detect the case when pages are not contiguous. Fix the problem by properly detecting when found page has larger offset than expected. Fixes: d126d43fSigned-off-by:
-
Yisheng Xie authored
commit 70feee0e upstream. Kefeng reported that when running the follow test, the mlock count in meminfo will increase permanently: [1] testcase linux:~ # cat test_mlockal grep Mlocked /proc/meminfo for j in `seq 0 10` do for i in `seq 4 15` do ./p_mlockall >> log & done sleep 0.2 done # wait some time to let mlock counter decrease and 5s may not enough sleep 5 grep Mlocked /proc/meminfo linux:~ # cat p_mlockall.c #include <sys/mman.h> #include <stdlib.h> #include <stdio.h> #define SPACE_LEN 4096 int main(int argc, char ** argv) { int ret; void *adr = malloc(SPACE_LEN); if (!adr) return -1; ret = mlockall(MCL_CURRENT | MCL_FUTURE); printf("mlcokall ret = %d\n", ret); ret = munlockall(); printf("munlcokall ret = %d\n", ret); free(adr); return 0; } In __munlock_pagevec() we should decrement NR_MLOCK for each page where we clear the PageMlocked flag. Commit 1ebb7cc6 ("mm: munlock: batch NR_MLOCK zone state updates") has introduced a bug where we don't decrement NR_MLOCK for pages where we clear the flag, but fail to isolate them from the lru list (e.g. when the pages are on some other cpu's percpu pagevec). Since PageMlocked stays cleared, the NR_MLOCK accounting gets permanently disrupted by this. Fix it by counting the number of page whose PageMlock flag is cleared. Fixes: 1ebb7cc6 (" mm: munlock: batch NR_MLOCK zone state updates") Link: http://lkml.kernel.org/r/1495678405-54569-1-git-send-email-xieyisheng1@huawei.comSigned-off-by:
Yisheng Xie <xieyisheng1@huawei.com> Reported-by:
Kefeng Wang <wangkefeng.wang@huawei.com> Tested-by:
Andrew Morton <akpm@linux-foundation.org> Signed-off-by:
Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by:
-
Punit Agrawal authored
commit 30809f55 upstream. On failing to migrate a page, soft_offline_huge_page() performs the necessary update to the hugepage ref-count. But when !hugepage_migration_supported() , unmap_and_move_hugepage() also decrements the page ref-count for the hugepage. The combined behaviour leaves the ref-count in an inconsistent state. This leads to soft lockups when running the overcommitted hugepage test from mce-tests suite. Soft offlining pfn 0x83ed600 at process virtual address 0x400000000000 soft offline: 0x83ed600: migration failed 1, type 1fffc00000008008 (uptodate|head) INFO: rcu_preempt detected stalls on CPUs/tasks: Tasks blocked on level-0 rcu_node (CPUs 0-7): P2715 (detected by 7, t=5254 jiffies, g=963, c=962, q=321) thugetlb_overco R running task 0 2715 2685 0x00000008 Call trace: dump_backtrace+0x0/0x268 show_stack+0x24/0x30 sched_show_task+0x134/0x180 rcu_print_detail_task_stall_rnp+0x54/0x7c rcu_check_callbacks+0xa74/0xb08 update_process_times+0x34/0x60 tick_sched_handle.isra.7+0x38/0x70 tick_sched_timer+0x4c/0x98 __hrtimer_run_queues+0xc0/0x300 hrtimer_interrupt+0xac/0x228 arch_timer_handler_phys+0x3c/0x50 handle_percpu_devid_irq+0x8c/0x290 generic_handle_irq+0x34/0x50 __handle_domain_irq+0x68/0xc0 gic_handle_irq+0x5c/0xb0 Address this by changing the putback_active_hugepage() in soft_offline_huge_page() to putback_movable_pages(). This only triggers on systems that enable memory failure handling (ARCH_SUPPORTS_MEMORY_FAILURE) but not hugepage migration (!ARCH_ENABLE_HUGEPAGE_MIGRATION). I imagine this wasn't triggered as there aren't many systems running this configuration. [akpm@linux-foundation.org: remove dead comment, per Naoya] Link: http://lkml.kernel.org/r/20170525135146.32011-1-punit.agrawal@arm.comReported-by:
Manoj Iyer <manoj.iyer@canonical.com> Tested-by:
Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by:
Punit Agrawal <punit.agrawal@arm.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Mel Gorman <mgorman@techsingularity.net> Signed-off-by:
-
Patrik Jakobsson authored
commit 82bc9a42 upstream. With LVDS we were incorrectly picking the pre-programmed mode instead of the prefered mode provided by VBT. Make sure we pick the VBT mode if one is provided. It is likely that the mode read-out code is still wrong but this patch fixes the immediate problem on most machines. Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78562Signed-off-by:
Patrik Jakobsson <patrik.r.jakobsson@gmail.com> Link: http://patchwork.freedesktop.org/patch/msgid/20170418114332.12183-1-patrik.r.jakobsson@gmail.comSigned-off-by:
-
Thomas Gleixner authored
commit 478fe303 upstream. memcg_propagate_slab_attrs() abuses the sysfs attribute file functions to propagate settings from the root kmem_cache to a newly created kmem_cache. It does that with: attr->show(root, buf); attr->store(new, buf, strlen(bug); Aside of being a lazy and absurd hackery this is broken because it does not check the return value of the show() function. Some of the show() functions return 0 w/o touching the buffer. That means in such a case the store function is called with the stale content of the previous show(). That causes nonsense like invoking kmem_cache_shrink() on a newly created kmem_cache. In the worst case it would cause handing in an uninitialized buffer. This should be rewritten proper by adding a propagate() callback to those slub_attributes which must be propagated and avoid that insane conversion to and from ASCII, but that's too large for a hot fix. Check at least the return value of the show() function, so calling store() with stale content is prevented. Steven said: "It can cause a deadlock with get_online_cpus() that has been uncovered by recent cpu hotplug and lockdep changes that Thomas and Peter have been doing. Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(cpu_hotplug.lock); lock(slab_mutex); lock(cpu_hotplug.lock); lock(slab_mutex); *** DEADLOCK ***" Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1705201244540.2255@nanosSigned-off-by:
Thomas Gleixner <tglx@linutronix.de> Reported-by:
Steven Rostedt <rostedt@goodmis.org> Acked-by:
David Rientjes <rientjes@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by:
-
Alexander Tsoy authored
commit 1fc2e41f upstream. This model is actually called 92XXM2-8 in Windows driver. But since pin configs for M22 and M28 are identical, just reuse M22 quirk. Fixes external microphone (tested) and probably docking station ports (not tested). Signed-off-by:
Alexander Tsoy <alexander@tsoy.me> Signed-off-by:
Takashi Iwai <tiwai@suse.de> Signed-off-by:
-
Nicolas Iooss authored
commit ff5a2016 upstream. Commit 5b5e0928 ("lib/vsprintf.c: remove %Z support") removed some usages of format %Z but forgot "%.2Zx". This makes clang 4.0 reports a -Wformat-extra-args warning because it does not know about %Z. Replace %Z with %z. Link: http://lkml.kernel.org/r/20170520090946.22562-1-nicolas.iooss_linux@m4x.orgSigned-off-by:
Nicolas Iooss <nicolas.iooss_linux@m4x.org> Cc: Harald Welte <laforge@gnumonks.org> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by:
-
Alex Deucher authored
commit 58d7e3e4 upstream. Even if the vblank period would allow it, it still seems to be problematic on some cards. v2: fix logic inversion (Nils) bug: https://bugs.freedesktop.org/show_bug.cgi?id=96868Acked-by:
Christian König <christian.koenig@amd.com> Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> Signed-off-by:
-
Sebastian Reichel authored
commit 5165da59 upstream. Since v4.9 i2c-tiny-usb generates the below call trace and longer works, since it can't communicate with the USB device. The reason is, that since v4.9 the USB stack checks, that the buffer it should transfer is DMA capable. This was a requirement since v2.2 days, but it usually worked nevertheless. [ 17.504959] ------------[ cut here ]------------ [ 17.505488] WARNING: CPU: 0 PID: 93 at drivers/usb/core/hcd.c:1587 usb_hcd_map_urb_for_dma+0x37c/0x570 [ 17.506545] transfer buffer not dma capable [ 17.507022] Modules linked in: [ 17.507370] CPU: 0 PID: 93 Comm: i2cdetect Not tainted 4.11.0-rc8+ #10 [ 17.508103] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1 04/01/2014 [ 17.509039] Call Trace: [ 17.509320] ? dump_stack+0x5c/0x78 [ 17.509714] ? __warn+0xbe/0xe0 [ 17.510073] ? warn_slowpath_fmt+0x5a/0x80 [ 17.510532] ? nommu_map_sg+0xb0/0xb0 [ 17.510949] ? usb_hcd_map_urb_for_dma+0x37c/0x570 [ 17.511482] ? usb_hcd_submit_urb+0x336/0xab0 [ 17.511976] ? wait_for_completion_timeout+0x12f/0x1a0 [ 17.512549] ? wait_for_completion_timeout+0x65/0x1a0 [ 17.513125] ? usb_start_wait_urb+0x65/0x160 [ 17.513604] ? usb_control_msg+0xdc/0x130 [ 17.514061] ? usb_xfer+0xa4/0x2a0 [ 17.514445] ? __i2c_transfer+0x108/0x3c0 [ 17.514899] ? i2c_transfer+0x57/0xb0 [ 17.515310] ? i2c_smbus_xfer_emulated+0x12f/0x590 [ 17.515851] ? _raw_spin_unlock_irqrestore+0x11/0x20 [ 17.516408] ? i2c_smbus_xfer+0x125/0x330 [ 17.516876] ? i2c_smbus_xfer+0x125/0x330 [ 17.517329] ? i2cdev_ioctl_smbus+0x1c1/0x2b0 [ 17.517824] ? i2cdev_ioctl+0x75/0x1c0 [ 17.518248] ? do_vfs_ioctl+0x9f/0x600 [ 17.518671] ? vfs_write+0x144/0x190 [ 17.519078] ? SyS_ioctl+0x74/0x80 [ 17.519463] ? entry_SYSCALL_64_fastpath+0x1e/0xad [ 17.519959] ---[ end trace d047c04982f5ac50 ]--- Signed-off-by:
Sebastian Reichel <sebastian.reichel@collabora.co.uk> Reviewed-by:
Till Harbaum <till@harbaum.org> Signed-off-by:
Wolfram Sang <wsa@the-dreams.de> Signed-off-by:
-
Davide Caratti authored
[ Upstream commit 804ec7eb ] sometimes ICMP replies to INIT chunks are ignored by the client, even if the encapsulated SCTP headers match an open socket. This happens when the ICMP packet is carried by a paged skb: use skb_header_pointer() to read packet contents beyond the SCTP header, so that chunk header and initiate tag are validated correctly. v2: - don't use skb_header_pointer() to read the transport header, since icmp_socket_deliver() already puts these 8 bytes in the linear area. - change commit message to make specific reference to INIT chunks. Signed-off-by:
Davide Caratti <dcaratti@redhat.com> Acked-by:
Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Acked-by:
Vlad Yasevich <vyasevich@gmail.com> Reviewed-by:
Xin Long <lucien.xin@gmail.com> Signed-off-by:
David S. Miller <davem@davemloft.net> Signed-off-by:
-
Wei Wang authored
[ Upstream commit ba615f67 ] Fastopen API should be used to perform fastopen operations on the TCP socket. It does not make sense to use fastopen API to perform disconnect by calling it with AF_UNSPEC. The fastopen data path is also prone to race conditions and bugs when using with AF_UNSPEC. One issue reported and analyzed by Vegard Nossum is as follows: +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Thread A: Thread B: ------------------------------------------------------------------------ sendto() - tcp_sendmsg() - sk_stream_memory_free() = 0 - goto wait_for_sndbuf - sk_stream_wait_memory() - sk_wait_event() // sleep | sendto(flags=MSG_FASTOPEN, dest_addr=AF_UNSPEC) | - tcp_sendmsg() | - tcp_sendmsg_fastopen() | - __inet_stream_connect() | - tcp_disconnect() //because of AF_UNSPEC | - tcp_transmit_skb()// send RST | - return 0; // no reconnect! | - sk_stream_wait_connect() | - sock_error() | - xchg(&sk->sk_err, 0) | - return -ECONNRESET - ... // wake up, see sk->sk_err == 0 - skb_entail() on TCP_CLOSE socket If the connection is reopened then we will send a brand new SYN packet after thread A has already queued a buffer. At this point I think the socket internal state (sequence numbers etc.) becomes messed up. When the new connection is closed, the FIN-ACK is rejected because the sequence number is outside the window. The other side tries to retransmit, but __tcp_retransmit_skb() calls tcp_trim_head() on an empty skb which corrupts the skb data length and hits a BUG() in copy_and_csum_bits(). +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ Hence, this patch adds a check for AF_UNSPEC in the fastopen data path and return EOPNOTSUPP to user if such case happens. Fixes: cf60af03 ("tcp: Fast Open client - sendmsg(MSG_FASTOPEN)") Reported-by:
Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by:
Wei Wang <weiwan@google.com> Signed-off-by:
Eric Dumazet <edumazet@google.com> Signed-off-by:
-
Eric Dumazet authored
[ Upstream commit 232cd35d ] Andrey Konovalov and idaifish@gmail.com reported crashes caused by one skb shared_info being overwritten from __ip6_append_data() Andrey program lead to following state : copy -4200 datalen 2000 fraglen 2040 maxfraglen 2040 alloclen 2048 transhdrlen 0 offset 0 fraggap 6200 The skb_copy_and_csum_bits(skb_prev, maxfraglen, data + transhdrlen, fraggap, 0); is overwriting skb->head and skb_shared_info Since we apparently detect this rare condition too late, move the code earlier to even avoid allocating skb and risking crashes. Once again, many thanks to Andrey and syzkaller team. Signed-off-by:
Andrey Konovalov <andreyknvl@google.com> Tested-by:
-
Bjørn Mork authored
[ Upstream commit 486181bc ] In their infinite wisdom, and never ending quest for end user frustration, Lenovo has decided to use a new USB device ID for the wwan modules in their 2017 laptops. The actual hardware is still the Sierra Wireless EM7455 or EM7430, depending on region. Signed-off-by:
Bjørn Mork <bjorn@mork.no> Signed-off-by:
-
David S. Miller authored
[ Upstream commit 7dd7eb95 ] Do not use unsigned variables to see if it returns a negative error or not. Fixes: 2423496a ("ipv6: Prevent overrun when parsing v6 header options") Reported-by:
Julia Lawall <julia.lawall@lip6.fr> Signed-off-by:
-
Craig Gallek authored
[ Upstream commit 2423496a ] The KASAN warning repoted below was discovered with a syzkaller program. The reproducer is basically: int s = socket(AF_INET6, SOCK_RAW, NEXTHDR_HOP); send(s, &one_byte_of_data, 1, MSG_MORE); send(s, &more_than_mtu_bytes_data, 2000, 0); The socket() call sets the nexthdr field of the v6 header to NEXTHDR_HOP, the first send call primes the payload with a non zero byte of data, and the second send call triggers the fragmentation path. The fragmentation code tries to parse the header options in order to figure out where to insert the fragment option. Since nexthdr points to an invalid option, the calculation of the size of the network header can made to be much larger than the linear section of the skb and data is read outside of it. This fix makes ip6_find_1stfrag return an error if it detects running out-of-bounds. [ 42.361487] ================================================================== [ 42.364412] BUG: KASAN: slab-out-of-bounds in ip6_fragment+0x11c8/0x3730 [ 42.365471] Read of size 840 at addr ffff88000969e798 by task ip6_fragment-oo/3789 [ 42.366469] [ 42.366696] CPU: 1 PID: 3789 Comm: ip6_fragment-oo Not tainted 4.11.0+ #41 [ 42.367628] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.1-1ubuntu1 04/01/2014 [ 42.368824] Call Trace: [ 42.369183] dump_stack+0xb3/0x10b [ 42.369664] print_address_description+0x73/0x290 [ 42.370325] kasan_report+0x252/0x370 [ 42.370839] ? ip6_fragment+0x11c8/0x3730 [ 42.371396] check_memory_region+0x13c/0x1a0 [ 42.371978] memcpy+0x23/0x50 [ 42.372395] ip6_fragment+0x11c8/0x3730 [ 42.372920] ? nf_ct_expect_unregister_notifier+0x110/0x110 [ 42.373681] ? ip6_copy_metadata+0x7f0/0x7f0 [ 42.374263] ? ip6_forward+0x2e30/0x2e30 [ 42.374803] ip6_finish_output+0x584/0x990 [ 42.375350] ip6_output+0x1b7/0x690 [ 42.375836] ? ip6_finish_output+0x990/0x990 [ 42.376411] ? ip6_fragment+0x3730/0x3730 [ 42.376968] ip6_local_out+0x95/0x160 [ 42.377471] ip6_send_skb+0xa1/0x330 [ 42.377969] ip6_push_pending_frames+0xb3/0xe0 [ 42.378589] rawv6_sendmsg+0x2051/0x2db0 [ 42.379129] ? rawv6_bind+0x8b0/0x8b0 [ 42.379633] ? _copy_from_user+0x84/0xe0 [ 42.380193] ? debug_check_no_locks_freed+0x290/0x290 [ 42.380878] ? ___sys_sendmsg+0x162/0x930 [ 42.381427] ? rcu_read_lock_sched_held+0xa3/0x120 [ 42.382074] ? sock_has_perm+0x1f6/0x290 [ 42.382614] ? ___sys_sendmsg+0x167/0x930 [ 42.383173] ? lock_downgrade+0x660/0x660 [ 42.383727] inet_sendmsg+0x123/0x500 [ 42.384226] ? inet_sendmsg+0x123/0x500 [ 42.384748] ? inet_recvmsg+0x540/0x540 [ 42.385263] sock_sendmsg+0xca/0x110 [ 42.385758] SYSC_sendto+0x217/0x380 [ 42.386249] ? SYSC_connect+0x310/0x310 [ 42.386783] ? __might_fault+0x110/0x1d0 [ 42.387324] ? lock_downgrade+0x660/0x660 [ 42.387880] ? __fget_light+0xa1/0x1f0 [ 42.388403] ? __fdget+0x18/0x20 [ 42.388851] ? sock_common_setsockopt+0x95/0xd0 [ 42.389472] ? SyS_setsockopt+0x17f/0x260 [ 42.390021] ? entry_SYSCALL_64_fastpath+0x5/0xbe [ 42.390650] SyS_sendto+0x40/0x50 [ 42.391103] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.391731] RIP: 0033:0x7fbbb711e383 [ 42.392217] RSP: 002b:00007ffff4d34f28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c [ 42.393235] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fbbb711e383 [ 42.394195] RDX: 0000000000001000 RSI: 00007ffff4d34f60 RDI: 0000000000000003 [ 42.395145] RBP: 0000000000000046 R08: 00007ffff4d34f40 R09: 0000000000000018 [ 42.396056] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000400aad [ 42.396598] R13: 0000000000000066 R14: 00007ffff4d34ee0 R15: 00007fbbb717af00 [ 42.397257] [ 42.397411] Allocated by task 3789: [ 42.397702] save_stack_trace+0x16/0x20 [ 42.398005] save_stack+0x46/0xd0 [ 42.398267] kasan_kmalloc+0xad/0xe0 [ 42.398548] kasan_slab_alloc+0x12/0x20 [ 42.398848] __kmalloc_node_track_caller+0xcb/0x380 [ 42.399224] __kmalloc_reserve.isra.32+0x41/0xe0 [ 42.399654] __alloc_skb+0xf8/0x580 [ 42.400003] sock_wmalloc+0xab/0xf0 [ 42.400346] __ip6_append_data.isra.41+0x2472/0x33d0 [ 42.400813] ip6_append_data+0x1a8/0x2f0 [ 42.401122] rawv6_sendmsg+0x11ee/0x2db0 [ 42.401505] inet_sendmsg+0x123/0x500 [ 42.401860] sock_sendmsg+0xca/0x110 [ 42.402209] ___sys_sendmsg+0x7cb/0x930 [ 42.402582] __sys_sendmsg+0xd9/0x190 [ 42.402941] SyS_sendmsg+0x2d/0x50 [ 42.403273] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.403718] [ 42.403871] Freed by task 1794: [ 42.404146] save_stack_trace+0x16/0x20 [ 42.404515] save_stack+0x46/0xd0 [ 42.404827] kasan_slab_free+0x72/0xc0 [ 42.405167] kfree+0xe8/0x2b0 [ 42.405462] skb_free_head+0x74/0xb0 [ 42.405806] skb_release_data+0x30e/0x3a0 [ 42.406198] skb_release_all+0x4a/0x60 [ 42.406563] consume_skb+0x113/0x2e0 [ 42.406910] skb_free_datagram+0x1a/0xe0 [ 42.407288] netlink_recvmsg+0x60d/0xe40 [ 42.407667] sock_recvmsg+0xd7/0x110 [ 42.408022] ___sys_recvmsg+0x25c/0x580 [ 42.408395] __sys_recvmsg+0xd6/0x190 [ 42.408753] SyS_recvmsg+0x2d/0x50 [ 42.409086] entry_SYSCALL_64_fastpath+0x1f/0xbe [ 42.409513] [ 42.409665] The buggy address belongs to the object at ffff88000969e780 [ 42.409665] which belongs to the cache kmalloc-512 of size 512 [ 42.410846] The buggy address is located 24 bytes inside of [ 42.410846] 512-byte region [ffff88000969e780, ffff88000969e980) [ 42.411941] The buggy address belongs to the page: [ 42.412405] page:ffffea000025a780 count:1 mapcount:0 mapping: (null) index:0x0 compound_mapcount: 0 [ 42.413298] flags: 0x100000000008100(slab|head) [ 42.413729] raw: 0100000000008100 0000000000000000 0000000000000000 00000001800c000c [ 42.414387] raw: ffffea00002a9500 0000000900000007 ffff88000c401280 0000000000000000 [ 42.415074] page dumped because: kasan: bad access detected [ 42.415604] [ 42.415757] Memory state around the buggy address: [ 42.416222] ffff88000969e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.416904] ffff88000969e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 42.417591] >ffff88000969e980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 42.418273] ^ [ 42.418588] ffff88000969ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419273] ffff88000969ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 42.419882] ================================================================== Reported-by:
Craig Gallek <kraig@google.com> Signed-off-by:
-
Soheil Hassas Yeganeh authored
[ Upstream commit bafbb9c7 ] tcp_ack() can call tcp_fragment() which may dededuct the value tp->fackets_out when MSS changes. When prior_fackets is larger than tp->fackets_out, tcp_clean_rtx_queue() can invoke tcp_update_reordering() with negative values. This results in absurd tp->reodering values higher than sysctl_tcp_max_reordering. Note that tcp_update_reordering indeeds sets tp->reordering to min(sysctl_tcp_max_reordering, metric), but because the comparison is signed, a negative metric always wins. Fixes: c7caf8d3 ("[TCP]: Fix reord detection due to snd_una covered holes") Reported-by:
Rebecca Isaacs <risaacs@google.com> Signed-off-by:
Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by:
Neal Cardwell <ncardwell@google.com> Signed-off-by:
Yuchung Cheng <ycheng@google.com> Signed-off-by:
-
Eric Dumazet authored
[ Upstream commit fdcee2cb ] SCTP needs fixes similar to 83eaddab ("ipv6/dccp: do not inherit ipv6_mc_list from parent"), otherwise bad things can happen. Signed-off-by:
-
Xin Long authored
[ Upstream commit dbc2b5e9 ] Commit 0ca50d12 ("sctp: fix src address selection if using secondary addresses") has fixed a src address selection issue when using secondary addresses for ipv4. Now sctp ipv6 also has the similar issue. When using a secondary address, sctp_v6_get_dst tries to choose the saddr which has the most same bits with the daddr by sctp_v6_addr_match_len. It may make some cases not work as expected. hostA: [1] fd21:356b:459a:cf10::11 (eth1) [2] fd21:356b:459a:cf20::11 (eth2) hostB: [a] fd21:356b:459a:cf30::2 (eth1) [b] fd21:356b:459a:cf40::2 (eth2) route from hostA to hostB: fd21:356b:459a:cf30::/64 dev eth1 metric 1024 mtu 1500 The expected path should be: fd21:356b:459a:cf10::11 <-> fd21:356b:459a:cf30::2 But addr[2] matches addr[a] more bits than addr[1] does, according to sctp_v6_addr_match_len. It causes the path to be: fd21:356b:459a:cf20::11 <-> fd21:356b:459a:cf30::2 This patch is to fix it with the same way as Marcelo's fix for sctp ipv4. As no ip_dev_find for ipv6, this patch is to use ipv6_chk_addr to check if the saddr is in a dev instead. Note that for backwards compatibility, it will still do the addr_match_len check here when no optimal is found. Reported-by:
Patrick Talbert <ptalbert@redhat.com> Signed-off-by:
-
Yuchung Cheng authored
[ Upstream commit b451e5d2 ] This patch fixes a bug in splitting an SKB during SACK processing. Specifically if an skb contains multiple packets and is only partially sacked in the higher sequences, tcp_match_sack_to_skb() splits the skb and marks the second fragment as SACKed. The current code further attempts rounding up the first fragment to MSS boundaries. But it misses a boundary condition when the rounded-up fragment size (pkt_len) is exactly skb size. Spliting such an skb is pointless and causses a kernel warning and aborts the SACK processing. This patch universally checks such over-split before calling tcp_fragment to prevent these unnecessary warnings. Fixes: adb92db8 ("tcp: Make SACK code to split only at mss boundaries") Signed-off-by:
-
Julian Wiedmann authored
[ Upstream commit 25e2c341 ] Access card->dev only after checking whether's its valid. Signed-off-by:
Julian Wiedmann <jwi@linux.vnet.ibm.com> Reviewed-by:
Ursula Braun <ubraun@linux.vnet.ibm.com> Signed-off-by:
-
Julian Wiedmann authored
[ Upstream commit 2d2ebb3e ] commit b4d72c08 ("qeth: bridgeport support - basic control") broke the support for OSM and OSN devices as follows: As OSM and OSN are L2 only, qeth_core_probe_device() does an early setup by loading the l2 discipline and calling qeth_l2_probe_device(). In this context, adding the l2-specific bridgeport sysfs attributes via qeth_l2_create_device_attributes() hits a BUG_ON in fs/sysfs/group.c, since the basic sysfs infrastructure for the device hasn't been established yet. Note that OSN actually has its own unique sysfs attributes (qeth_osn_devtype), so the additional attributes shouldn't be created at all. For OSM, add a new qeth_l2_devtype that contains all the common and l2-specific sysfs attributes. When qeth_core_probe_device() does early setup for OSM or OSN, assign the corresponding devtype so that the ccwgroup probe code creates the full set of sysfs attributes. This allows us to skip qeth_l2_create_device_attributes() in case of an early setup. Any device that can't do early setup will initially have only the generic sysfs attributes, and when it's probed later qeth_l2_probe_device() adds the l2-specific attributes. If an early-setup device is removed (by calling ccwgroup_ungroup()), device_unregister() will - using the devtype - delete the l2-specific attributes before qeth_l2_remove_device() is called. So make sure to not remove them twice. What complicates the issue is that qeth_l2_probe_device() and qeth_l2_remove_device() is also called on a device when its layer2 attribute changes (ie. its layer mode is switched). For early-setup devices this wouldn't work properly - we wouldn't remove the l2-specific attributes when switching to L3. But switching the layer mode doesn't actually make any sense; we already decided that the device can only operate in L2! So just refuse to switch the layer mode on such devices. Note that OSN doesn't have a layer2 attribute, so we only need to special-case OSM. Based on an initial patch by Ursula Braun. Fixes: b4d72c08 ("qeth: bridgeport support - basic control") Signed-off-by:
-
Ursula Braun authored
[ Upstream commit 9111e788 ] When setting up the device from within the layer discipline's probe routine, creating the layer-specific sysfs attributes can fail. Report this error back to the caller, and handle it by releasing the layer discipline. Signed-off-by:
-
Eric Dumazet authored
[ Upstream commit 657831ff ] syzkaller found a way to trigger double frees from ip_mc_drop_socket() It turns out that leave a copy of parent mc_list at accept() time, which is very bad. Very similar to commit 8b485ce6 ("tcp: do not inherit fastopen_req from parent") Initial report from Pray3r, completed by Andrey one. Thanks a lot to them ! Signed-off-by:
Pray3r <pray3r.z@gmail.com> Reported-by:
-
Eric Dumazet authored
commit f6ba8d33 upstream. I should have known that lowering skb->truesize was dangerous :/ In case packets are not leaving the host via a standard Ethernet device, but looped back to local sockets, bad things can happen, as reported by Michael Madsen ( https://bugzilla.kernel.org/show_bug.cgi?id=195713 ) So instead of tweaking skb->truesize, lets change skb->destructor and keep a reference on the owner socket via its sk_refcnt. Fixes: f2f872f9 ("netem: Introduce skb_orphan_partial() helper") Signed-off-by:
Michael Madsen <mkm@nabto.com> Signed-off-by:
-
Greg Kroah-Hartman authored
Revert "stackprotector: Increase the per-task stack canary's random range from 32 bits to 64 bits on 64-bit platforms" This reverts commit 609a3e81 which is commit 5ea30e4e upstream. It shouldn't have been backported to 3.18, as we do not have get_random_long() in that kernel tree. Reported-by:
Philip Müller <philm@manjaro.org> Cc: Daniel Micay <danielmicay@gmail.com> Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: Rik van Riel <riel@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Arjan van Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-hardening@lists.openwall.com Cc: Ingo Molnar <mingo@kernel.org> Signed-off-by:
-
- 25 May, 2017 11 commits
-
-
Greg Kroah-Hartman authored
-
Maksim Salau authored
commit 0bd193d6 upstream. get_version_reply is not freed if function returns with success. Fixes: 942a4873 ("usb: misc: legousbtower: Fix buffers on stack") Reported-by:
Heikki Krogerus <heikki.krogerus@linux.intel.com> Signed-off-by:
Maksim Salau <maksim.salau@gmail.com> Signed-off-by:
-
Julius Werner authored
commit b299cde2 upstream. /dev/mem currently allows mmap() mappings that wrap around the end of the physical address space, which should probably be illegal. It circumvents the existing STRICT_DEVMEM permission check because the loop immediately terminates (as the start address is already higher than the end address). On the x86_64 architecture it will then cause a panic (from the BUG(start >= end) in arch/x86/mm/pat.c:reserve_memtype()). This patch adds an explicit check to make sure offset + size will not wrap around in the physical address type. Signed-off-by:
Julius Werner <jwerner@chromium.org> Signed-off-by:
-
Lukas Wunner authored
commit ea00353f upstream. Laurent Pinchart reported that the Renesas R-Car H2 Lager board (r8a7790) crashes during suspend tests. Geert Uytterhoeven managed to reproduce the issue on an M2-W Koelsch board (r8a7791): It occurs when the PME scan runs, once per second. During PME scan, the PCI host bridge (rcar-pci) registers are accessed while its module clock has already been disabled, leading to the crash. One reproducer is to configure s2ram to use "s2idle" instead of "deep" suspend: # echo 0 > /sys/module/printk/parameters/console_suspend # echo s2idle > /sys/power/mem_sleep # echo mem > /sys/power/state Another reproducer is to write either "platform" or "processors" to /sys/power/pm_test. It does not (or is less likely) to happen during full system suspend ("core" or "none") because system suspend also disables timers, and thus the workqueue handling PME scans no longer runs. Geert believes the issue may still happen in the small window between disabling module clocks and disabling timers: # echo 0 > /sys/module/printk/parameters/console_suspend # echo platform > /sys/power/pm_test # Or "processors" # echo mem > /sys/power/state (Make sure CONFIG_PCI_RCAR_GEN2 and CONFIG_USB_OHCI_HCD_PCI are enabled.) Rafael Wysocki agrees that PME scans should be suspended before the host bridge registers become inaccessible. To that end, queue the task on a workqueue that gets frozen before devices suspend. Rafael notes however that as a result, some wakeup events may be missed if they are delivered via PME from a device without working IRQ (which hence must be polled) and occur after the workqueue has been frozen. If that turns out to be an issue in practice, it may be possible to solve it by calling pci_pme_list_scan() once directly from one of the host bridge's pm_ops callbacks. Stacktrace for posterity: PM: Syncing filesystems ... [ 38.566237] done. PM: Preparing system for sleep (mem) Freezing user space processes ... [ 38.579813] (elapsed 0.001 seconds) done. Freezing remaining freezable tasks ... (elapsed 0.001 seconds) done. PM: Suspending system (mem) PM: suspend of devices complete after 152.456 msecs PM: late suspend of devices complete after 2.809 msecs PM: noirq suspend of devices complete after 29.863 msecs suspend debug: Waiting for 5 second(s). Unhandled fault: asynchronous external abort (0x1211) at 0x00000000 pgd = c0003000 [00000000] *pgd=80000040004003, *pmd=00000000 Internal error: : 1211 [#1] SMP ARM Modules linked in: CPU: 1 PID: 20 Comm: kworker/1:1 Not tainted 4.9.0-rc1-koelsch-00011-g68db9bc8 #3383 Hardware name: Generic R8A7791 (Flattened Device Tree) Workqueue: events pci_pme_list_scan task: eb56e140 task.stack: eb58e000 PC is at pci_generic_config_read+0x64/0x6c LR is at rcar_pci_cfg_base+0x64/0x84 pc : [<c041d7b4>] lr : [<c04309a0>] psr: 600d0093 sp : eb58fe98 ip : c041d750 fp : 00000008 r10: c0e2283c r9 : 00000000 r8 : 600d0013 r7 : 00000008 r6 : eb58fed6 r5 : 00000002 r4 : eb58feb4 r3 : 00000000 r2 : 00000044 r1 : 00000008 r0 : 00000000 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment user Control: 30c5387d Table: 6a9f6c80 DAC: 55555555 Process kworker/1:1 (pid: 20, stack limit = 0xeb58e210) Stack: (0xeb58fe98 to 0xeb590000) fe80: 00000002 00000044 fea0: eb6f5800 c041d9b0 eb58feb4 00000008 00000044 00000000 eb78a000 eb78a000 fec0: 00000044 00000000 eb9aff00 c0424bf0 eb78a000 00000000 eb78a000 c0e22830 fee0: ea8a6fc0 c0424c5c eaae79c0 c0424ce0 eb55f380 c0e22838 eb9a9800 c0235fbc ff00: eb55f380 c0e22838 eb55f380 eb9a9800 eb9a9800 eb58e000 eb9a9824 c0e02100 ff20: eb55f398 c02366c4 eb56e140 eb5631c0 00000000 eb55f380 c023641c 00000000 ff40: 00000000 00000000 00000000 c023a928 cd105598 00000000 40506a34 eb55f380 ff60: 00000000 00000000 dead4ead ffffffff ffffffff eb58ff74 eb58ff74 00000000 ff80: 00000000 dead4ead ffffffff ffffffff eb58ff90 eb58ff90 eb58ffac eb5631c0 ffa0: c023a844 00000000 00000000 c0206d68 00000000 00000000 00000000 00000000 ffc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 ffe0: 00000000 00000000 00000000 00000000 00000013 00000000 3a81336c 10ccd1dd [<c041d7b4>] (pci_generic_config_read) from [<c041d9b0>] (pci_bus_read_config_word+0x58/0x80) [<c041d9b0>] (pci_bus_read_config_word) from [<c0424bf0>] (pci_check_pme_status+0x34/0x78) [<c0424bf0>] (pci_check_pme_status) from [<c0424c5c>] (pci_pme_wakeup+0x28/0x54) [<c0424c5c>] (pci_pme_wakeup) from [<c0424ce0>] (pci_pme_list_scan+0x58/0xb4) [<c0424ce0>] (pci_pme_list_scan) from [<c0235fbc>] (process_one_work+0x1bc/0x308) [<c0235fbc>] (process_one_work) from [<c02366c4>] (worker_thread+0x2a8/0x3e0) [<c02366c4>] (worker_thread) from [<c023a928>] (kthread+0xe4/0xfc) [<c023a928>] (kthread) from [<c0206d68>] (ret_from_fork+0x14/0x2c) Code: ea000000 e5903000 f57ff04f e3a00000 (e5843000) ---[ end trace 667d43ba3aa9e589 ]--- Fixes: df17e62e ("PCI: Add support for polling PME state on suspended legacy PCI devices") Reported-and-tested-by:
Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com> Reported-and-tested-by:
Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by:
Lukas Wunner <lukas@wunner.de> Signed-off-by:
Bjorn Helgaas <bhelgaas@google.com> Reviewed-by:
Laurent Pinchart <laurent.pinchart@ideasonboard.com> Acked-by:
Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se> Cc: Simon Horman <horms+renesas@verge.net.au> Cc: Yinghai Lu <yinghai@kernel.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Signed-off-by:
-
David Woodhouse authored
commit 6bccc7f4 upstream. In the PCI_MMAP_PROCFS case when the address being passed by the user is a 'user visible' resource address based on the bus window, and not the actual contents of the resource, that's what we need to be checking it against. Signed-off-by:
David Woodhouse <dwmw@amazon.co.uk> Signed-off-by:
-
Thomas Gleixner authored
commit 30e7d894 upstream. Enabling the tracer selftest triggers occasionally the warning in text_poke(), which warns when the to be modified page is not marked reserved. The reason is that the tracer selftest installs kprobes on functions marked __init for testing. These probes are removed after the tests, but that removal schedules the delayed kprobes_optimizer work, which will do the actual text poke. If the work is executed after the init text is freed, then the warning triggers. The bug can be reproduced reliably when the work delay is increased. Flush the optimizer work and wait for the optimizing/unoptimizing lists to become empty before returning from the kprobes tracer selftest. That ensures that all operations which were queued due to the probes removal have completed. Link: http://lkml.kernel.org/r/20170516094802.76a468bb@gandalf.local.homeSigned-off-by:
Masami Hiramatsu <mhiramat@kernel.org> Fixes: 6274de49 ("kprobes: Support delayed unoptimizing") Signed-off-by:
-
Al Viro authored
commit a8c39544 upstream. failing sys_wait4() won't fill struct rusage... Signed-off-by:
Al Viro <viro@zeniv.linux.org.uk> Signed-off-by:
-
Johan Hovold authored
commit 41318a2b upstream. Add missing endianness conversion when using the USB device-descriptor idProduct field to apply a hardware quirk. Fixes: 1ba47da5 ("uwb: add the i1480 DFU driver") Signed-off-by:
Johan Hovold <johan@kernel.org> Signed-off-by:
-
Daniel Micay authored
stackprotector: Increase the per-task stack canary's random range from 32 bits to 64 bits on 64-bit platforms commit 5ea30e4e upstream. The stack canary is an 'unsigned long' and should be fully initialized to random data rather than only 32 bits of random data. Signed-off-by:
Daniel Micay <danielmicay@gmail.com> Acked-by:
Arjan van de Ven <arjan@linux.intel.com> Acked-by:
Rik van Riel <riel@redhat.com> Acked-by:
Kees Cook <keescook@chromium.org> Cc: Arjan van Ven <arjan@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170504133209.3053-1-danielmicay@gmail.comSigned-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
-
James Hogan authored
commit 3a158a62 upstream. The metag implementation of strncpy_from_user() doesn't validate the src pointer, which could allow reading of arbitrary kernel memory. Add a short access_ok() check to prevent that. Its still possible for it to read across the user/kernel boundary, but it will invariably reach a NUL character after only 9 bytes, leaking only a static kernel address being loaded into D0Re0 at the beginning of __start, which is acceptable for the immediate fix. Reported-by:
James Hogan <james.hogan@imgtec.com> Cc: linux-metag@vger.kernel.org Signed-off-by:
-
James Hogan authored
commit 8a8b5663 upstream. The __user_bad() macro used by access_ok() has a few corner cases noticed by Al Viro where it doesn't behave correctly: - The kernel range check has off by 1 errors which permit access to the first and last byte of the kernel mapped range. - The kernel range check ends at LINCORE_BASE rather than META_MEMORY_LIMIT, which is ineffective when the kernel is in global space (an extremely uncommon configuration). There are a couple of other shortcomings here too: - Access to the whole of the other address space is permitted (i.e. the global half of the address space when the kernel is in local space). This isn't ideal as it could theoretically still contain privileged mappings set up by the bootloader. - The size argument is unused, permitting user copies which start on valid pages at the end of the user address range and cross the boundary into the kernel address space (e.g. addr = 0x3ffffff0, size > 0x10). It isn't very convenient to add size checks when disallowing certain regions, and it seems far safer to be sure and explicit about what userland is able to access, so invert the logic to allow certain regions instead, and fix the off by 1 errors and missing size checks. This also allows the get_fs() == KERNEL_DS check to be more easily optimised into the user address range case. We now have 3 such allowed regions: - The user address range (incorporating the get_fs() == KERNEL_DS check). - NULL (some kernel code expects this to work, and we'll always catch the fault anyway). - The core code memory region. Fixes: 373cd784 ("metag: Memory handling") Reported-by:
-
