user/sven/linux.git/include, branch v4.14.181

x86: Fix early boot crash on gcc-10, third try

2020-05-20T06:17:15Z

commit a9a3ed1eff3601b63aea4fb462d8b3b92c7c1e7e upstream. ... or the odyssey of trying to disable the stack protector for the function which generates the stack canary value. The whole story started with Sergei reporting a boot crash with a kernel built with gcc-10: Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139 Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013 Call Trace: dump_stack panic ? start_secondary __stack_chk_fail start_secondary secondary_startup_64 -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary This happens because gcc-10 tail-call optimizes the last function call in start_secondary() - cpu_startup_entry() - and thus emits a stack canary check which fails because the canary value changes after the boot_init_stack_canary() call. To fix that, the initial attempt was to mark the one function which generates the stack canary with: __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused) however, using the optimize attribute doesn't work cumulatively as the attribute does not add to but rather replaces previously supplied optimization options - roughly all -fxxx options. The key one among them being -fno-omit-frame-pointer and thus leading to not present frame pointer - frame pointer which the kernel needs. The next attempt to prevent compilers from tail-call optimizing the last function call cpu_startup_entry(), shy of carving out start_secondary() into a separate compilation unit and building it with -fno-stack-protector, was to add an empty asm(""). This current solution was short and sweet, and reportedly, is supported by both compilers but we didn't get very far this time: future (LTO?) optimization passes could potentially eliminate this, which leads us to the third attempt: having an actual memory barrier there which the compiler cannot ignore or move around etc. That should hold for a long time, but hey we said that about the other two solutions too so... Reported-by: Sergei Trofimovich Signed-off-by: Borislav Petkov Tested-by: Kalle Valo Cc: Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org Signed-off-by: Greg Kroah-Hartman

ALSA: rawmidi: Fix racy buffer resize under concurrent accesses

2020-05-20T06:17:14Z

commit c1f6e3c818dd734c30f6a7eeebf232ba2cf3181d upstream. The rawmidi core allows user to resize the runtime buffer via ioctl, and this may lead to UAF when performed during concurrent reads or writes: the read/write functions unlock the runtime lock temporarily during copying form/to user-space, and that's the race window. This patch fixes the hole by introducing a reference counter for the runtime buffer read/write access and returns -EBUSY error when the resize is performed concurrently against read/write. Note that the ref count field is a simple integer instead of refcount_t here, since the all contexts accessing the buffer is basically protected with a spinlock, hence we need no expensive atomic ops. Also, note that this busy check is needed only against read / write functions, and not in receive/transmit callbacks; the race can happen only at the spinlock hole mentioned in the above, while the whole function is protected for receive / transmit callbacks. Reported-by: butt3rflyh4ck Cc: Link: https://lore.kernel.org/r/CAFcO6XMWpUVK_yzzCpp8_XP7+=oUpQvuBeCbMffEDkpe8jWrfg@mail.gmail.com Link: https://lore.kernel.org/r/s5heerw3r5z.wl-tiwai@suse.de Signed-off-by: Takashi Iwai Signed-off-by: Greg Kroah-Hartman

gcc-10 warnings: fix low-hanging fruit

2020-05-20T06:17:09Z

commit 9d82973e032e246ff5663c9805fbb5407ae932e3 upstream. Due to a bug-report that was compiler-dependent, I updated one of my machines to gcc-10. That shows a lot of new warnings. Happily they seem to be mostly the valid kind, but it's going to cause a round of churn for getting rid of them.. This is the really low-hanging fruit of removing a couple of zero-sized arrays in some core code. We have had a round of these patches before, and we'll have many more coming, and there is nothing special about these except that they were particularly trivial, and triggered more warnings than most. Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

pnp: Use list_for_each_entry() instead of open coding

2020-05-20T06:17:09Z

commit 01b2bafe57b19d9119413f138765ef57990921ce upstream. Aside from good practice, this avoids a warning from gcc 10: ./include/linux/kernel.h:997:3: warning: array subscript -31 is outside array bounds of ‘struct list_head[1]’ [-Warray-bounds] 997 | ((type *)(__mptr - offsetof(type, member))); }) | ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ./include/linux/list.h:493:2: note: in expansion of macro ‘container_of’ 493 | container_of(ptr, type, member) | ^~~~~~~~~~~~ ./include/linux/pnp.h:275:30: note: in expansion of macro ‘list_entry’ 275 | #define global_to_pnp_dev(n) list_entry(n, struct pnp_dev, global_list) | ^~~~~~~~~~ ./include/linux/pnp.h:281:11: note: in expansion of macro ‘global_to_pnp_dev’ 281 | (dev) != global_to_pnp_dev(&pnp_global); \ | ^~~~~~~~~~~~~~~~~ arch/x86/kernel/rtc.c:189:2: note: in expansion of macro ‘pnp_for_each_dev’ 189 | pnp_for_each_dev(dev) { Because the common code doesn't cast the starting list_head to the containing struct. Signed-off-by: Jason Gunthorpe [ rjw: Whitespace adjustments ] Signed-off-by: Rafael J. Wysocki Signed-off-by: Greg Kroah-Hartman

netfilter: conntrack: avoid gcc-10 zero-length-bounds warning

2020-05-20T06:17:09Z

[ Upstream commit 2c407aca64977ede9b9f35158e919773cae2082f ] gcc-10 warns around a suspicious access to an empty struct member: net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_alloc': net/netfilter/nf_conntrack_core.c:1522:9: warning: array subscript 0 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[0]'} [-Wzero-length-bounds] 1522 | memset(&ct->__nfct_init_offset[0], 0, | ^~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from net/netfilter/nf_conntrack_core.c:37: include/net/netfilter/nf_conntrack.h:90:5: note: while referencing '__nfct_init_offset' 90 | u8 __nfct_init_offset[0]; | ^~~~~~~~~~~~~~~~~~ The code is correct but a bit unusual. Rework it slightly in a way that does not trigger the warning, using an empty struct instead of an empty array. There are probably more elegant ways to do this, but this is the smallest change. Fixes: c41884ce0562 ("netfilter: conntrack: avoid zeroing timer") Signed-off-by: Arnd Bergmann Signed-off-by: Pablo Neira Ayuso Signed-off-by: Sasha Levin

blktrace: Protect q->blk_trace with RCU

2020-05-20T06:17:03Z

commit c780e86dd48ef6467a1146cf7d0fe1e05a635039 upstream. KASAN is reporting that __blk_add_trace() has a use-after-free issue when accessing q->blk_trace. Indeed the switching of block tracing (and thus eventual freeing of q->blk_trace) is completely unsynchronized with the currently running tracing and thus it can happen that the blk_trace structure is being freed just while __blk_add_trace() works on it. Protect accesses to q->blk_trace by RCU during tracing and make sure we wait for the end of RCU grace period when shutting down tracing. Luckily that is rare enough event that we can afford that. Note that postponing the freeing of blk_trace to an RCU callback should better be avoided as it could have unexpected user visible side-effects as debugfs files would be still existing for a short while block tracing has been shut down. Link: https://bugzilla.kernel.org/show_bug.cgi?id=205711 CC: stable@vger.kernel.org Reviewed-by: Chaitanya Kulkarni Reviewed-by: Ming Lei Tested-by: Ming Lei Reviewed-by: Bart Van Assche Reported-by: Tristan Madani Signed-off-by: Jan Kara Signed-off-by: Jens Axboe [bwh: Backported to 4.14: adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

net: ipv6_stub: use ip6_dst_lookup_flow instead of ip6_dst_lookup

2020-05-20T06:17:02Z

commit 6c8991f41546c3c472503dff1ea9daaddf9331c2 upstream. ipv6_stub uses the ip6_dst_lookup function to allow other modules to perform IPv6 lookups. However, this function skips the XFRM layer entirely. All users of ipv6_stub->ip6_dst_lookup use ip_route_output_flow (via the ip_route_output_key and ip_route_output helpers) for their IPv4 lookups, which calls xfrm_lookup_route(). This patch fixes this inconsistent behavior by switching the stub to ip6_dst_lookup_flow, which also calls xfrm_lookup_route(). This requires some changes in all the callers, as these two functions take different arguments and have different return types. Fixes: 5f81bd2e5d80 ("ipv6: export a stub for IPv6 symbols used by vxlan") Reported-by: Xiumei Mu Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller [bwh: Backported to 4.14: - Drop change in lwt_bpf.c - Delete now-unused "ret" in mlx5e_route_lookup_ipv6() - Initialise "out_dev" in mlx5e_create_encap_header_ipv6() to avoid introducing a spurious "may be used uninitialised" warning - Adjust filenames, context, indentation] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

net: ipv6: add net argument to ip6_dst_lookup_flow

2020-05-20T06:17:02Z

commit c4e85f73afb6384123e5ef1bba3315b2e3ad031e upstream. This will be used in the conversion of ipv6_stub to ip6_dst_lookup_flow, as some modules currently pass a net argument without a socket to ip6_dst_lookup. This is equivalent to commit 343d60aada5a ("ipv6: change ipv6_stub_impl.ipv6_dst_lookup to take net argument"). Signed-off-by: Sabrina Dubroca Signed-off-by: David S. Miller [bwh: Backported to 4.14: adjust context] Signed-off-by: Ben Hutchings Signed-off-by: Greg Kroah-Hartman

net: stricter validation of untrusted gso packets

2020-05-20T06:16:56Z

[ Upstream commit 9274124f023b5c56dc4326637d4f787968b03607 ] Syzkaller again found a path to a kernel crash through bad gso input: a packet with transport header extending beyond skb_headlen(skb). Tighten validation at kernel entry: - Verify that the transport header lies within the linear section. To avoid pulling linux/tcp.h, verify just sizeof tcphdr. tcp_gso_segment will call pskb_may_pull (th->doff * 4) before use. - Match the gso_type against the ip_proto found by the flow dissector. Fixes: bfd5f4a3d605 ("packet: Add GSO/csum offload support.") Reported-by: syzbot Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

mac80211: add ieee80211_is_any_nullfunc()

2020-05-10T08:29:03Z

commit 30b2f0be23fb40e58d0ad2caf8702c2a44cda2e1 upstream. commit 08a5bdde3812 ("mac80211: consider QoS Null frames for STA_NULLFUNC_ACKED") Fixed a bug where we failed to take into account a nullfunc frame can be either non-QoS or QoS. It turns out there is at least one more bug in ieee80211_sta_tx_notify(), introduced in commit 7b6ddeaf27ec ("mac80211: use QoS NDP for AP probing"), where we forgot to check for the QoS variant and so assumed the QoS nullfunc frame never went out Fix this by adding a helper ieee80211_is_any_nullfunc() which consolidates the check for non-QoS and QoS nullfunc frames. Replace existing compound conditionals and add a couple more missing checks for QoS variant. Signed-off-by: Thomas Pedersen Link: https://lore.kernel.org/r/20200114055940.18502-3-thomas@adapt-ip.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman