- 26 Feb, 2017 13 commits
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Ben Hutchings authored
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Eric Dumazet authored
commit ccf7abb9 upstream. Splicing from TCP socket is vulnerable when a packet with URG flag is received and stored into receive queue. __tcp_splice_read() returns 0, and sk_wait_data() immediately returns since there is the problematic skb in queue. This is a nice way to burn cpu (aka infinite loop) and trigger soft lockups. Again, this gem was found by syzkaller tool. Fixes: 9c55e01c ("[TCP]: Splice receive support.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Dmitry Vyukov <dvyukov@google.com> Cc: Willy Tarreau <w@1wt.eu> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Andrey Konovalov authored
commit 5edabca9 upstream. In the current DCCP implementation an skb for a DCCP_PKT_REQUEST packet is forcibly freed via __kfree_skb in dccp_rcv_state_process if dccp_v6_conn_request successfully returns. However, if IPV6_RECVPKTINFO is set on a socket, the address of the skb is saved to ireq->pktopts and the ref count for skb is incremented in dccp_v6_conn_request, so skb is still in use. Nevertheless, it gets freed in dccp_rcv_state_process. Fix by calling consume_skb instead of doing goto discard and therefore calling __kfree_skb. Similar fixes for TCP: fb7e2399 [TCP]: skb is unexpectedly freed. 0aea76d3 tcp: SYN packets are now simply consumed Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Eric Dumazet authored
commit 34b2cef2 upstream. Andrey Konovalov got crashes in __ip_options_echo() when a NULL skb->dst is accessed. ipv4_pktinfo_prepare() should not drop the dst if (evil) IP options are present. We could refine the test to the presence of ts_needtime or srr, but IP options are not often used, so let's be conservative. Thanks to syzkaller team for finding this bug. Fixes: d826eb14 ("ipv4: PKTINFO doesnt need dst reference") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Eric Dumazet authored
commit 7892032c upstream. Andrey Konovalov reported out of bound accesses in ip6gre_err() If GRE flags contains GRE_KEY, the following expression *(((__be32 *)p) + (grehlen / 4) - 1) accesses data ~40 bytes after the expected point, since grehlen includes the size of IPv6 headers. Let's use a "struct gre_base_hdr *greh" pointer to make this code more readable. p[1] becomes greh->protocol. grhlen is the GRE header length. Fixes: c12b395a ("gre: Support GRE over IPv6") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: - Add #include <net/gre.h>, added earlier upstream - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Gu Zheng authored
commit 497de07d upstream. This change was missed the tmpfs modification in In CVE-2016-7097 commit 07393101 ("posix_acl: Clear SGID bit when setting file permissions") It can test by xfstest generic/375, which failed to clear setgid bit in the following test case on tmpfs: touch $testfile chown 100:100 $testfile chmod 2755 $testfile _runas -u 100 -g 101 -- setfacl -m u::rwx,g::rwx,o::rwx $testfile Signed-off-by: Gu Zheng <guzheng1@huawei.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Johan Hovold authored
commit 146cc8a1 upstream. The current implementation failed to detect short transfers when attempting to read the line state, and also, to make things worse, logged the content of the uninitialised heap transfer buffer. Fixes: abf492e7 ("USB: kl5kusb105: fix DMA buffers on stack") Fixes: 1da177e4 ("Linux-2.6.12-rc2") Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Stephen Smalley authored
commit 0c461cb7 upstream. SELinux tries to support setting/clearing of /proc/pid/attr attributes from the shell by ignoring terminating newlines and treating an attribute value that begins with a NUL or newline as an attempt to clear the attribute. However, the test for clearing attributes has always been wrong; it has an off-by-one error, and this could further lead to reading past the end of the allocated buffer since commit bb646cdb ("proc_pid_attr_write(): switch to memdup_user()"). Fix the off-by-one error. Even with this fix, setting and clearing /proc/pid/attr attributes from the shell is not straightforward since the interface does not support multiple write() calls (so shells that write the value and newline separately will set and then immediately clear the attribute, requiring use of echo -n to set the attribute), whereas trying to use echo -n "" to clear the attribute causes the shell to skip the write() call altogether since POSIX says that a zero-length write causes no side effects. Thus, one must use echo -n to set and echo without -n to clear, as in the following example: $ echo -n unconfined_u:object_r:user_home_t:s0 > /proc/$$/attr/fscreate $ cat /proc/$$/attr/fscreate unconfined_u:object_r:user_home_t:s0 $ echo "" > /proc/$$/attr/fscreate $ cat /proc/$$/attr/fscreate Note the use of /proc/$$ rather than /proc/self, as otherwise the cat command will read its own attribute value, not that of the shell. There are no users of this facility to my knowledge; possibly we should just get rid of it. UPDATE: Upon further investigation it appears that a local process with the process:setfscreate permission can cause a kernel panic as a result of this bug. This patch fixes CVE-2017-2618. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> [PM: added the update about CVE-2017-2618 to the commit description] Signed-off-by: Paul Moore <paul@paul-moore.com> Signed-off-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Steve Rutherford authored
commit 129a72a0 upstream. Introduces segemented_write_std. Switches from emulated reads/writes to standard read/writes in fxsave, fxrstor, sgdt, and sidt. This fixes CVE-2017-2584, a longstanding kernel memory leak. Since commit 283c95d0 ("KVM: x86: emulate FXSAVE and FXRSTOR", 2016-11-09), which is luckily not yet in any final release, this would also be an exploitable kernel memory *write*! Reported-by: Dmitry Vyukov <dvyukov@google.com> Fixes: 96051572 Fixes: 283c95d0Suggested-by: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Steve Rutherford <srutherford@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.16: drop changes to em_fxsave(), em_fxrstor()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Paolo Bonzini authored
commit 33ab9110 upstream. This is CVE-2017-2583. On Intel this causes a failed vmentry because SS's type is neither 3 nor 7 (even though the manual says this check is only done for usable SS, and the dmesg splat says that SS is unusable!). On AMD it's worse: svm.c is confused and sets CPL to 0 in the vmcb. The fix fabricates a data segment descriptor when SS is set to a null selector, so that CPL and SS.DPL are set correctly in the VMCS/vmcb. Furthermore, only allow setting SS to a NULL selector if SS.RPL < 3; this in turn ensures CPL < 3 because RPL must be equal to CPL. Thanks to Andy Lutomirski and Willy Tarreau for help in analyzing the bug and deciphering the manuals. Reported-by: Xiaohan Zhang <zhangxiaohan1@huawei.com> Fixes: 79d5b4c3 Cc: stable@nongnu.org Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Eryu Guan authored
commit 3a4b77cd upstream. Ralf Spenneberg reported that he hit a kernel crash when mounting a modified ext4 image. And it turns out that kernel crashed when calculating fs overhead (ext4_calculate_overhead()), this is because the image has very large s_first_meta_bg (debug code shows it's 842150400), and ext4 overruns the memory in count_overhead() when setting bitmap buffer, which is PAGE_SIZE. ext4_calculate_overhead(): buf = get_zeroed_page(GFP_NOFS); <=== PAGE_SIZE buffer blks = count_overhead(sb, i, buf); count_overhead(): for (j = ext4_bg_num_gdb(sb, grp); j > 0; j--) { <=== j = 842150400 ext4_set_bit(EXT4_B2C(sbi, s++), buf); <=== buffer overrun count++; } This can be reproduced easily for me by this script: #!/bin/bash rm -f fs.img mkdir -p /mnt/ext4 fallocate -l 16M fs.img mke2fs -t ext4 -O bigalloc,meta_bg,^resize_inode -F fs.img debugfs -w -R "ssv first_meta_bg 842150400" fs.img mount -o loop fs.img /mnt/ext4 Fix it by validating s_first_meta_bg first at mount time, and refusing to mount if its value exceeds the largest possible meta_bg number. Reported-by: Ralf Spenneberg <ralf@os-t.de> Signed-off-by: Eryu Guan <guaneryu@gmail.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu> Reviewed-by: Andreas Dilger <adilger@dilger.ca> [bwh: Backported to 3.16: use EXT4_HAS_INCOMPAT_FEATURE()] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Jim Mattson authored
commit ef85b673 upstream. When L2 exits to L0 due to "exception or NMI", software exceptions (#BP and #OF) for which L1 has requested an intercept should be handled by L1 rather than L0. Previously, only hardware exceptions were forwarded to L1. Signed-off-by: Jim Mattson <jmattson@google.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Eric W. Biederman authored
commit d2921684 upstream. CAI Qian <caiqian@redhat.com> pointed out that the semantics of shared subtrees make it possible to create an exponentially increasing number of mounts in a mount namespace. mkdir /tmp/1 /tmp/2 mount --make-rshared / for i in $(seq 1 20) ; do mount --bind /tmp/1 /tmp/2 ; done Will create create 2^20 or 1048576 mounts, which is a practical problem as some people have managed to hit this by accident. As such CVE-2016-6213 was assigned. Ian Kent <raven@themaw.net> described the situation for autofs users as follows: > The number of mounts for direct mount maps is usually not very large because of > the way they are implemented, large direct mount maps can have performance > problems. There can be anywhere from a few (likely case a few hundred) to less > than 10000, plus mounts that have been triggered and not yet expired. > > Indirect mounts have one autofs mount at the root plus the number of mounts that > have been triggered and not yet expired. > > The number of autofs indirect map entries can range from a few to the common > case of several thousand and in rare cases up to between 30000 and 50000. I've > not heard of people with maps larger than 50000 entries. > > The larger the number of map entries the greater the possibility for a large > number of active mounts so it's not hard to expect cases of a 1000 or somewhat > more active mounts. So I am setting the default number of mounts allowed per mount namespace at 100,000. This is more than enough for any use case I know of, but small enough to quickly stop an exponential increase in mounts. Which should be perfect to catch misconfigurations and malfunctioning programs. For anyone who needs a higher limit this can be changed by writing to the new /proc/sys/fs/mount-max sysctl. Tested-by: CAI Qian <caiqian@redhat.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com> [bwh: Backported to 3.16: - Use ACCESS_ONCE() instead of READ_ONCE() - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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- 23 Feb, 2017 27 commits
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Ben Hutchings authored
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Linus Torvalds authored
commit d05c5f7b upstream. We truncated the possible read iterator to s_maxbytes in commit c2a9737f ("vfs,mm: fix a dead loop in truncate_inode_pages_range()"), but our end condition handling was wrong: it's not an error to try to read at the end of the file. Reading past the end should return EOF (0), not EINVAL. See for example https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1649342 http://lists.gnu.org/archive/html/bug-coreutils/2016-12/msg00008.html where a md5sum of a maximally sized file fails because the final read is exactly at s_maxbytes. Fixes: c2a9737f ("vfs,mm: fix a dead loop in truncate_inode_pages_range()") Reported-by: Joseph Salisbury <joseph.salisbury@canonical.com> Cc: Wei Fang <fangwei1@huawei.com> Cc: Christoph Hellwig <hch@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Takashi Iwai authored
commit 3aa02cb6 upstream. Currently kill_fasync() is called outside the stream lock in snd_pcm_period_elapsed(). This is potentially racy, since the stream may get released even during the irq handler is running. Although snd_pcm_release_substream() calls snd_pcm_drop(), this doesn't guarantee that the irq handler finishes, thus the kill_fasync() call outside the stream spin lock may be invoked after the substream is detached, as recently reported by KASAN. As a quick workaround, move kill_fasync() call inside the stream lock. The fasync is rarely used interface, so this shouldn't have a big impact from the performance POV. Ideally, we should implement some sync mechanism for the proper finish of stream and irq handler. But this oneliner should suffice for most cases, so far. Reported-by: Baozeng Ding <sploving1@gmail.com> Signed-off-by: Takashi Iwai <tiwai@suse.de> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Eric Dumazet authored
commit b98b0bc8 upstream. CAP_NET_ADMIN users should not be allowed to set negative sk_sndbuf or sk_rcvbuf values, as it can lead to various memory corruptions, crashes, OOM... Note that before commit 82981930 ("net: cleanups in sock_setsockopt()"), the bug was even more serious, since SO_SNDBUF and SO_RCVBUF were vulnerable. This needs to be backported to all known linux kernels. Again, many thanks to syzkaller team for discovering this gem. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Al Viro authored
commit 128394ef upstream. Both damn things interpret userland pointers embedded into the payload; worse, they are actually traversing those. Leaving aside the bad API design, this is very much _not_ safe to call with KERNEL_DS. Bail out early if that happens. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Marcelo Ricardo Leitner authored
commit bf911e98 upstream. Andrey Konovalov reported that KASAN detected that SCTP was using a slab beyond the boundaries. It was caused because when handling out of the blue packets in function sctp_sf_ootb() it was checking the chunk len only after already processing the first chunk, validating only for the 2nd and subsequent ones. The fix is to just move the check upwards so it's also validated for the 1st chunk. Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Reviewed-by: Xin Long <lucien.xin@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: moved code is slightly different] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Zhou Chengming authored
commit 93362fa4 upstream. Fixes CVE-2016-9191, proc_sys_readdir doesn't drop reference added by grab_header when return from !dir_emit_dots path. It can cause any path called unregister_sysctl_table will wait forever. The calltrace of CVE-2016-9191: [ 5535.960522] Call Trace: [ 5535.963265] [<ffffffff817cdaaf>] schedule+0x3f/0xa0 [ 5535.968817] [<ffffffff817d33fb>] schedule_timeout+0x3db/0x6f0 [ 5535.975346] [<ffffffff817cf055>] ? wait_for_completion+0x45/0x130 [ 5535.982256] [<ffffffff817cf0d3>] wait_for_completion+0xc3/0x130 [ 5535.988972] [<ffffffff810d1fd0>] ? wake_up_q+0x80/0x80 [ 5535.994804] [<ffffffff8130de64>] drop_sysctl_table+0xc4/0xe0 [ 5536.001227] [<ffffffff8130de17>] drop_sysctl_table+0x77/0xe0 [ 5536.007648] [<ffffffff8130decd>] unregister_sysctl_table+0x4d/0xa0 [ 5536.014654] [<ffffffff8130deff>] unregister_sysctl_table+0x7f/0xa0 [ 5536.021657] [<ffffffff810f57f5>] unregister_sched_domain_sysctl+0x15/0x40 [ 5536.029344] [<ffffffff810d7704>] partition_sched_domains+0x44/0x450 [ 5536.036447] [<ffffffff817d0761>] ? __mutex_unlock_slowpath+0x111/0x1f0 [ 5536.043844] [<ffffffff81167684>] rebuild_sched_domains_locked+0x64/0xb0 [ 5536.051336] [<ffffffff8116789d>] update_flag+0x11d/0x210 [ 5536.057373] [<ffffffff817cf61f>] ? mutex_lock_nested+0x2df/0x450 [ 5536.064186] [<ffffffff81167acb>] ? cpuset_css_offline+0x1b/0x60 [ 5536.070899] [<ffffffff810fce3d>] ? trace_hardirqs_on+0xd/0x10 [ 5536.077420] [<ffffffff817cf61f>] ? mutex_lock_nested+0x2df/0x450 [ 5536.084234] [<ffffffff8115a9f5>] ? css_killed_work_fn+0x25/0x220 [ 5536.091049] [<ffffffff81167ae5>] cpuset_css_offline+0x35/0x60 [ 5536.097571] [<ffffffff8115aa2c>] css_killed_work_fn+0x5c/0x220 [ 5536.104207] [<ffffffff810bc83f>] process_one_work+0x1df/0x710 [ 5536.110736] [<ffffffff810bc7c0>] ? process_one_work+0x160/0x710 [ 5536.117461] [<ffffffff810bce9b>] worker_thread+0x12b/0x4a0 [ 5536.123697] [<ffffffff810bcd70>] ? process_one_work+0x710/0x710 [ 5536.130426] [<ffffffff810c3f7e>] kthread+0xfe/0x120 [ 5536.135991] [<ffffffff817d4baf>] ret_from_fork+0x1f/0x40 [ 5536.142041] [<ffffffff810c3e80>] ? kthread_create_on_node+0x230/0x230 One cgroup maintainer mentioned that "cgroup is trying to offline a cpuset css, which takes place under cgroup_mutex. The offlining ends up trying to drain active usages of a sysctl table which apprently is not happening." The real reason is that proc_sys_readdir doesn't drop reference added by grab_header when return from !dir_emit_dots path. So this cpuset offline path will wait here forever. See here for details: http://www.openwall.com/lists/oss-security/2016/11/04/13 Fixes: f0c3b509 ("[readdir] convert procfs") Reported-by: CAI Qian <caiqian@redhat.com> Tested-by: Yang Shukui <yangshukui@huawei.com> Signed-off-by: Zhou Chengming <zhouchengming1@huawei.com> Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Linus Torvalds authored
Not upstream as it is not needed there. So a patch something like this might be a safe way to fix the potential infoleak in older kernels. THIS IS UNTESTED. It's a very obvious patch, though, so if it compiles it probably works. It just initializes the output variable with 0 in the inline asm description, instead of doing it in the exception handler. It will generate slightly worse code (a few unnecessary ALU operations), but it doesn't have any interactions with the exception handler implementation. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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EunTaik Lee authored
commit 9590232b upstream. There is a use-after-free problem in the ion driver. This is caused by a race condition in the ion_ioctl() function. A handle has ref count of 1 and two tasks on different cpus calls ION_IOC_FREE simultaneously. cpu 0 cpu 1 ------------------------------------------------------- ion_handle_get_by_id() (ref == 2) ion_handle_get_by_id() (ref == 3) ion_free() (ref == 2) ion_handle_put() (ref == 1) ion_free() (ref == 0 so ion_handle_destroy() is called and the handle is freed.) ion_handle_put() is called and it decreases the slub's next free pointer The problem is detected as an unaligned access in the spin lock functions since it uses load exclusive instruction. In some cases it corrupts the slub's free pointer which causes a mis-aligned access to the next free pointer.(kmalloc returns a pointer like ffffc0745b4580aa). And it causes lots of other hard-to-debug problems. This symptom is caused since the first member in the ion_handle structure is the reference count and the ion driver decrements the reference after it has been freed. To fix this problem client->lock mutex is extended to protect all the codes that uses the handle. Signed-off-by: Eun Taik Lee <eun.taik.lee@samsung.com> Reviewed-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Eric Dumazet authored
commit ac6e7800 upstream. With syzkaller help, Marco Grassi found a bug in TCP stack, crashing in tcp_collapse() Root cause is that sk_filter() can truncate the incoming skb, but TCP stack was not really expecting this to happen. It probably was expecting a simple DROP or ACCEPT behavior. We first need to make sure no part of TCP header could be removed. Then we need to adjust TCP_SKB_CB(skb)->end_seq Many thanks to syzkaller team and Marco for giving us a reproducer. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Marco Grassi <marco.gra@gmail.com> Reported-by: Vladis Dronov <vdronov@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Willem de Bruijn authored
commit 4f0c40d9 upstream. Dccp verifies packet integrity, including length, at initial rcv in dccp_invalid_packet, later pulls headers in dccp_enqueue_skb. A call to sk_filter in-between can cause __skb_pull to wrap skb->len. skb_copy_datagram_msg interprets this as a negative value, so (correctly) fails with EFAULT. The negative length is reported in ioctl SIOCINQ or possibly in a DCCP_WARN in dccp_close. Introduce an sk_receive_skb variant that caps how small a filter program can trim packets, and call this in dccp with the header length. Excessively trimmed packets are now processed normally and queued for reception as 0B payloads. Fixes: 7c657876 ("[DCCP]: Initial implementation") Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Willem de Bruijn authored
commit f4979fce upstream. Sockets can have a filter program attached that drops or trims incoming packets based on the filter program return value. Rose requires data packets to have at least ROSE_MIN_LEN bytes. It verifies this on arrival in rose_route_frame and unconditionally pulls the bytes in rose_recvmsg. The filter can trim packets to below this value in-between, causing pull to fail, leaving the partial header at the time of skb_copy_datagram_msg. Place a lower bound on the size to which sk_filter may trim packets by introducing sk_filter_trim_cap and call this for rose packets. Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net> [bwh: Backported to 3.16: adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Ben Hutchings authored
Extraxcted from commit e6afc8ac "udp: remove headers from UDP packets before queueing". Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Kees Cook authored
commit 2dc705a9 upstream. Copying color maps to userspace doesn't check the value of to->start, which will cause kernel heap buffer OOB read due to signedness wraps. CVE-2016-8405 Link: http://lkml.kernel.org/r/20170105224249.GA50925@beast Fixes: 1da177e4 ("Linux-2.6.12-rc2") Signed-off-by: Kees Cook <keescook@chromium.org> Reported-by: Peter Pi (@heisecode) of Trend Micro Cc: Min Chong <mchong@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: Tomi Valkeinen <tomi.valkeinen@ti.com> Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Phil Turnbull authored
commit c58d6c93 upstream. If nlh->nlmsg_len is zero then an infinite loop is triggered because 'skb_pull(skb, msglen);' pulls zero bytes. The calculation in nlmsg_len() underflows if 'nlh->nlmsg_len < NLMSG_HDRLEN' which bypasses the length validation and will later trigger an out-of-bound read. If the length validation does fail then the malformed batch message is copied back to userspace. However, we cannot do this because the nlh->nlmsg_len can be invalid. This leads to an out-of-bounds read in netlink_ack: [ 41.455421] ================================================================== [ 41.456431] BUG: KASAN: slab-out-of-bounds in memcpy+0x1d/0x40 at addr ffff880119e79340 [ 41.456431] Read of size 4294967280 by task a.out/987 [ 41.456431] ============================================================================= [ 41.456431] BUG kmalloc-512 (Not tainted): kasan: bad access detected [ 41.456431] ----------------------------------------------------------------------------- ... [ 41.456431] Bytes b4 ffff880119e79310: 00 00 00 00 d5 03 00 00 b0 fb fe ff 00 00 00 00 ................ [ 41.456431] Object ffff880119e79320: 20 00 00 00 10 00 05 00 00 00 00 00 00 00 00 00 ............... [ 41.456431] Object ffff880119e79330: 14 00 0a 00 01 03 fc 40 45 56 11 22 33 10 00 05 .......@EV."3... [ 41.456431] Object ffff880119e79340: f0 ff ff ff 88 99 aa bb 00 14 00 0a 00 06 fe fb ................ ^^ start of batch nlmsg with nlmsg_len=4294967280 ... [ 41.456431] Memory state around the buggy address: [ 41.456431] ffff880119e79400: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 41.456431] ffff880119e79480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 41.456431] >ffff880119e79500: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc [ 41.456431] ^ [ 41.456431] ffff880119e79580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc [ 41.456431] ffff880119e79600: fc fc fc fc fc fc fc fc fc fc fb fb fb fb fb fb [ 41.456431] ================================================================== Fix this with better validation of nlh->nlmsg_len and by setting NFNL_BATCH_FAILURE if any batch message fails length validation. CAP_NET_ADMIN is required to trigger the bugs. Fixes: 9ea2aa8b ("netfilter: nfnetlink: validate nfnetlink header from batch") Signed-off-by: Phil Turnbull <phil.turnbull@oracle.com> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> [bwh: Backported to 3.16: - We don't have an error list so don't call nfnl_err_reset() - Set 'success' variable instead of 'status'] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Benjamin Tissoires authored
commit 50220dea upstream. Plugging a Logitech DJ receiver with KASAN activated raises a bunch of out-of-bound readings. The fields are allocated up to MAX_USAGE, meaning that potentially, we do not have enough fields to fit the incoming values. Add checks and silence KASAN. Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Jiri Kosina <jkosina@suse.cz> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Lars-Peter Clausen authored
commit 38740a5b upstream. When using asynchronous read or write operations on the USB endpoints the issuer of the IO request is notified by calling the ki_complete() callback of the submitted kiocb when the URB has been completed. Calling this ki_complete() callback will free kiocb. Make sure that the structure is no longer accessed beyond that point, otherwise undefined behaviour might occur. Fixes: 2e4c7553 ("usb: gadget: f_fs: add aio support") Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com> [bwh: Backported to 3.16: - Adjust filename - We only use kiocb::private, not kiocb::ki_flags] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Peter Zijlstra authored
commit 321027c1 upstream. Di Shen reported a race between two concurrent sys_perf_event_open() calls where both try and move the same pre-existing software group into a hardware context. The problem is exactly that described in commit: f63a8daa ("perf: Fix event->ctx locking") ... where, while we wait for a ctx->mutex acquisition, the event->ctx relation can have changed under us. That very same commit failed to recognise sys_perf_event_context() as an external access vector to the events and thereby didn't apply the established locking rules correctly. So while one sys_perf_event_open() call is stuck waiting on mutex_lock_double(), the other (which owns said locks) moves the group about. So by the time the former sys_perf_event_open() acquires the locks, the context we've acquired is stale (and possibly dead). Apply the established locking rules as per perf_event_ctx_lock_nested() to the mutex_lock_double() for the 'move_group' case. This obviously means we need to validate state after we acquire the locks. Reported-by: Di Shen (Keen Lab) Tested-by: John Dias <joaodias@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kees Cook <keescook@chromium.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Min Chong <mchong@google.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: f63a8daa ("perf: Fix event->ctx locking") Link: http://lkml.kernel.org/r/20170106131444.GZ3174@twins.programming.kicks-ass.netSigned-off-by: Ingo Molnar <mingo@kernel.org> [bwh: Backported to 3.16: - Use ACCESS_ONCE() instead of READ_ONCE() - Test perf_event::group_flags instead of group_caps - Add the err_locked cleanup block, which we didn't need before - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Peter Zijlstra authored
commit 13005627 upstream. In case of: err_file: fput(event_file), we'll end up calling perf_release() which in turn will free the event. Do not then free the event _again_. Tested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: dvyukov@google.com Cc: eranian@google.com Cc: oleg@redhat.com Cc: panand@redhat.com Cc: sasha.levin@oracle.com Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160224174947.697350349@infradead.orgSigned-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Peter Zijlstra authored
commit f63a8daa upstream. There have been a few reported issues wrt. the lack of locking around changing event->ctx. This patch tries to address those. It avoids the whole rwsem thing; and while it appears to work, please give it some thought in review. What I did fail at is sensible runtime checks on the use of event->ctx, the RCU use makes it very hard. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20150123125834.209535886@infradead.orgSigned-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Peter Hurley authored
commit dd42bf11 upstream. Line discipline drivers may mistakenly misuse ldisc-related fields when initializing. For example, a failure to initialize tty->receive_room in the N_GIGASET_M101 line discipline was recently found and fixed [1]. Now, the N_X25 line discipline has been discovered accessing the previous line discipline's already-freed private data [2]. Harden the ldisc interface against misuse by initializing revelant tty fields before instancing the new line discipline. [1] commit fd98e941 Author: Tilman Schmidt <tilman@imap.cc> Date: Tue Jul 14 00:37:13 2015 +0200 isdn/gigaset: reset tty->receive_room when attaching ser_gigaset [2] Report from Sasha Levin <sasha.levin@oracle.com> [ 634.336761] ================================================================== [ 634.338226] BUG: KASAN: use-after-free in x25_asy_open_tty+0x13d/0x490 at addr ffff8800a743efd0 [ 634.339558] Read of size 4 by task syzkaller_execu/8981 [ 634.340359] ============================================================================= [ 634.341598] BUG kmalloc-512 (Not tainted): kasan: bad access detected ... [ 634.405018] Call Trace: [ 634.405277] dump_stack (lib/dump_stack.c:52) [ 634.405775] print_trailer (mm/slub.c:655) [ 634.406361] object_err (mm/slub.c:662) [ 634.406824] kasan_report_error (mm/kasan/report.c:138 mm/kasan/report.c:236) [ 634.409581] __asan_report_load4_noabort (mm/kasan/report.c:279) [ 634.411355] x25_asy_open_tty (drivers/net/wan/x25_asy.c:559 (discriminator 1)) [ 634.413997] tty_ldisc_open.isra.2 (drivers/tty/tty_ldisc.c:447) [ 634.414549] tty_set_ldisc (drivers/tty/tty_ldisc.c:567) [ 634.415057] tty_ioctl (drivers/tty/tty_io.c:2646 drivers/tty/tty_io.c:2879) [ 634.423524] do_vfs_ioctl (fs/ioctl.c:43 fs/ioctl.c:607) [ 634.427491] SyS_ioctl (fs/ioctl.c:622 fs/ioctl.c:613) [ 634.427945] entry_SYSCALL_64_fastpath (arch/x86/entry/entry_64.S:188) Cc: Tilman Schmidt <tilman@imap.cc> Cc: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Peter Zijlstra authored
commit 12ca6ad2 upstream. There's a race on CPU unplug where we free the swevent hash array while it can still have events on. This will result in a use-after-free which is BAD. Simply do not free the hash array on unplug. This leaves the thing around and no use-after-free takes place. When the last swevent dies, we do a for_each_possible_cpu() iteration anyway to clean these up, at which time we'll free it, so no leakage will occur. Reported-by: Sasha Levin <sasha.levin@oracle.com> Tested-by: Sasha Levin <sasha.levin@oracle.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Calvin Owens authored
commit f3951a37 upstream. In sg_common_write(), we free the block request and return -ENODEV if the device is detached in the middle of the SG_IO ioctl(). Unfortunately, sg_finish_rem_req() also tries to free srp->rq, so we end up freeing rq->cmd in the already free rq object, and then free the object itself out from under the current user. This ends up corrupting random memory via the list_head on the rq object. The most common crash trace I saw is this: ------------[ cut here ]------------ kernel BUG at block/blk-core.c:1420! Call Trace: [<ffffffff81281eab>] blk_put_request+0x5b/0x80 [<ffffffffa0069e5b>] sg_finish_rem_req+0x6b/0x120 [sg] [<ffffffffa006bcb9>] sg_common_write.isra.14+0x459/0x5a0 [sg] [<ffffffff8125b328>] ? selinux_file_alloc_security+0x48/0x70 [<ffffffffa006bf95>] sg_new_write.isra.17+0x195/0x2d0 [sg] [<ffffffffa006cef4>] sg_ioctl+0x644/0xdb0 [sg] [<ffffffff81170f80>] do_vfs_ioctl+0x90/0x520 [<ffffffff81258967>] ? file_has_perm+0x97/0xb0 [<ffffffff811714a1>] SyS_ioctl+0x91/0xb0 [<ffffffff81602afb>] tracesys+0xdd/0xe2 RIP [<ffffffff81281e04>] __blk_put_request+0x154/0x1a0 The solution is straightforward: just set srp->rq to NULL in the failure branch so that sg_finish_rem_req() doesn't attempt to re-free it. Additionally, since sg_rq_end_io() will never be called on the object when this happens, we need to free memory backing ->cmd if it isn't embedded in the object itself. KASAN was extremely helpful in finding the root cause of this bug. Signed-off-by: Calvin Owens <calvinowens@fb.com> Acked-by: Douglas Gilbert <dgilbert@interlog.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> [bwh: Backported to 3.16: - sg_finish_rem_req() would not free srp->rq->cmd so don't do it here either - Adjust context] Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Dan Carpenter authored
commit 93a97c50 upstream. If we can't allocate the resources in gigaset_initdriver() then we should return -ENOMEM instead of zero. Fixes: 2869b23e ("[PATCH] drivers/isdn/gigaset: new M101 driver (v2)") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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추지호 authored
commit b67d0dd7 upstream. Fix for bad memory access while disconnecting. netdev is freed before private data free, and dev is accessed after freeing netdev. This makes a slub problem, and it raise kernel oops with slub debugger config. Signed-off-by: Jiho Chu <jiho.chu@samsung.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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Marc Kleine-Budde authored
commit 332b05ca upstream. This patch adds a check to limit the number of can_filters that can be set via setsockopt on CAN_RAW sockets. Otherwise allocations > MAX_ORDER are not prevented resulting in a warning. Reference: https://lkml.org/lkml/2016/12/2/230Reported-by: Andrey Konovalov <andreyknvl@google.com> Tested-by: Andrey Konovalov <andreyknvl@google.com> Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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John David Anglin authored
commit febe4296 upstream. We have four routines in pacache.S that use temporary alias pages: copy_user_page_asm(), clear_user_page_asm(), flush_dcache_page_asm() and flush_icache_page_asm(). copy_user_page_asm() and clear_user_page_asm() don't purge the TLB entry used for the operation. flush_dcache_page_asm() and flush_icache_page_asm do purge the entry. Presumably, this was thought to optimize TLB use. However, the operation is quite heavy weight on PA 1.X processors as we need to take the TLB lock and a TLB broadcast is sent to all processors. This patch removes the purges from flush_dcache_page_asm() and flush_icache_page_asm. Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de> Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
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