linux-stable.git/include, branch v3.17.4 Linux kernel stable tree net: sctp: fix skb_over_panic when receiving malformed ASCONF chunks 2014-11-21T17:23:16+00:00 Daniel Borkmann dborkman@redhat.com 2014-10-09T20:55:31+00:00 35e95fae72ddb67ef94395d99abc48589ce17875 commit 9de7922bc709eee2f609cd01d98aaedc4cf5ea74 upstream. Commit 6f4c618ddb0 ("SCTP : Add paramters validity check for ASCONF chunk") added basic verification of ASCONF chunks, however, it is still possible to remotely crash a server by sending a special crafted ASCONF chunk, even up to pre 2.6.12 kernels: skb_over_panic: text:ffffffffa01ea1c3 len:31056 put:30768 head:ffff88011bd81800 data:ffff88011bd81800 tail:0x7950 end:0x440 dev:<NULL> ------------[ cut here ]------------ kernel BUG at net/core/skbuff.c:129! [...] Call Trace: <IRQ> [<ffffffff8144fb1c>] skb_put+0x5c/0x70 [<ffffffffa01ea1c3>] sctp_addto_chunk+0x63/0xd0 [sctp] [<ffffffffa01eadaf>] sctp_process_asconf+0x1af/0x540 [sctp] [<ffffffff8152d025>] ? _read_unlock_bh+0x15/0x20 [<ffffffffa01e0038>] sctp_sf_do_asconf+0x168/0x240 [sctp] [<ffffffffa01e3751>] sctp_do_sm+0x71/0x1210 [sctp] [<ffffffff8147645d>] ? fib_rules_lookup+0xad/0xf0 [<ffffffffa01e6b22>] ? sctp_cmp_addr_exact+0x32/0x40 [sctp] [<ffffffffa01e8393>] sctp_assoc_bh_rcv+0xd3/0x180 [sctp] [<ffffffffa01ee986>] sctp_inq_push+0x56/0x80 [sctp] [<ffffffffa01fcc42>] sctp_rcv+0x982/0xa10 [sctp] [<ffffffffa01d5123>] ? ipt_local_in_hook+0x23/0x28 [iptable_filter] [<ffffffff8148bdc9>] ? nf_iterate+0x69/0xb0 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0 [<ffffffff8148bf86>] ? nf_hook_slow+0x76/0x120 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0 [<ffffffff81496ded>] ip_local_deliver_finish+0xdd/0x2d0 [<ffffffff81497078>] ip_local_deliver+0x98/0xa0 [<ffffffff8149653d>] ip_rcv_finish+0x12d/0x440 [<ffffffff81496ac5>] ip_rcv+0x275/0x350 [<ffffffff8145c88b>] __netif_receive_skb+0x4ab/0x750 [<ffffffff81460588>] netif_receive_skb+0x58/0x60 This can be triggered e.g., through a simple scripted nmap connection scan injecting the chunk after the handshake, for example, ... -------------- INIT[ASCONF; ASCONF_ACK] -------------> <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------ -------------------- COOKIE-ECHO --------------------> <-------------------- COOKIE-ACK --------------------- ------------------ ASCONF; UNKNOWN ------------------> ... where ASCONF chunk of length 280 contains 2 parameters ... 1) Add IP address parameter (param length: 16) 2) Add/del IP address parameter (param length: 255) ... followed by an UNKNOWN chunk of e.g. 4 bytes. Here, the Address Parameter in the ASCONF chunk is even missing, too. This is just an example and similarly-crafted ASCONF chunks could be used just as well. The ASCONF chunk passes through sctp_verify_asconf() as all parameters passed sanity checks, and after walking, we ended up successfully at the chunk end boundary, and thus may invoke sctp_process_asconf(). Parameter walking is done with WORD_ROUND() to take padding into account. In sctp_process_asconf()'s TLV processing, we may fail in sctp_process_asconf_param() e.g., due to removal of the IP address that is also the source address of the packet containing the ASCONF chunk, and thus we need to add all TLVs after the failure to our ASCONF response to remote via helper function sctp_add_asconf_response(), which basically invokes a sctp_addto_chunk() adding the error parameters to the given skb. When walking to the next parameter this time, we proceed with ... length = ntohs(asconf_param->param_hdr.length); asconf_param = (void *)asconf_param + length; ... instead of the WORD_ROUND()'ed length, thus resulting here in an off-by-one that leads to reading the follow-up garbage parameter length of 12336, and thus throwing an skb_over_panic for the reply when trying to sctp_addto_chunk() next time, which implicitly calls the skb_put() with that length. Fix it by using sctp_walk_params() [ which is also used in INIT parameter processing ] macro in the verification *and* in ASCONF processing: it will make sure we don't spill over, that we walk parameters WORD_ROUND()'ed. Moreover, we're being more defensive and guard against unknown parameter types and missized addresses. Joint work with Vlad Yasevich. Fixes: b896b82be4ae ("[SCTP] ADDIP: Support for processing incoming ASCONF_ACK chunks.") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Acked-by: Neil Horman <nhorman@tuxdriver.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 9de7922bc709eee2f609cd01d98aaedc4cf5ea74 upstream.

Commit 6f4c618ddb0 ("SCTP : Add paramters validity check for
ASCONF chunk") added basic verification of ASCONF chunks, however,
it is still possible to remotely crash a server by sending a
special crafted ASCONF chunk, even up to pre 2.6.12 kernels:

skb_over_panic: text:ffffffffa01ea1c3 len:31056 put:30768
 head:ffff88011bd81800 data:ffff88011bd81800 tail:0x7950
 end:0x440 dev:<NULL>
 ------------[ cut here ]------------
kernel BUG at net/core/skbuff.c:129!
[...]
Call Trace:
 <IRQ>
 [<ffffffff8144fb1c>] skb_put+0x5c/0x70
 [<ffffffffa01ea1c3>] sctp_addto_chunk+0x63/0xd0 [sctp]
 [<ffffffffa01eadaf>] sctp_process_asconf+0x1af/0x540 [sctp]
 [<ffffffff8152d025>] ? _read_unlock_bh+0x15/0x20
 [<ffffffffa01e0038>] sctp_sf_do_asconf+0x168/0x240 [sctp]
 [<ffffffffa01e3751>] sctp_do_sm+0x71/0x1210 [sctp]
 [<ffffffff8147645d>] ? fib_rules_lookup+0xad/0xf0
 [<ffffffffa01e6b22>] ? sctp_cmp_addr_exact+0x32/0x40 [sctp]
 [<ffffffffa01e8393>] sctp_assoc_bh_rcv+0xd3/0x180 [sctp]
 [<ffffffffa01ee986>] sctp_inq_push+0x56/0x80 [sctp]
 [<ffffffffa01fcc42>] sctp_rcv+0x982/0xa10 [sctp]
 [<ffffffffa01d5123>] ? ipt_local_in_hook+0x23/0x28 [iptable_filter]
 [<ffffffff8148bdc9>] ? nf_iterate+0x69/0xb0
 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0
 [<ffffffff8148bf86>] ? nf_hook_slow+0x76/0x120
 [<ffffffff81496d10>] ? ip_local_deliver_finish+0x0/0x2d0
 [<ffffffff81496ded>] ip_local_deliver_finish+0xdd/0x2d0
 [<ffffffff81497078>] ip_local_deliver+0x98/0xa0
 [<ffffffff8149653d>] ip_rcv_finish+0x12d/0x440
 [<ffffffff81496ac5>] ip_rcv+0x275/0x350
 [<ffffffff8145c88b>] __netif_receive_skb+0x4ab/0x750
 [<ffffffff81460588>] netif_receive_skb+0x58/0x60

This can be triggered e.g., through a simple scripted nmap
connection scan injecting the chunk after the handshake, for
example, ...

  -------------- INIT[ASCONF; ASCONF_ACK] ------------->
  <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------
  -------------------- COOKIE-ECHO -------------------->
  <-------------------- COOKIE-ACK ---------------------
  ------------------ ASCONF; UNKNOWN ------------------>

... where ASCONF chunk of length 280 contains 2 parameters ...

  1) Add IP address parameter (param length: 16)
  2) Add/del IP address parameter (param length: 255)

... followed by an UNKNOWN chunk of e.g. 4 bytes. Here, the
Address Parameter in the ASCONF chunk is even missing, too.
This is just an example and similarly-crafted ASCONF chunks
could be used just as well.

The ASCONF chunk passes through sctp_verify_asconf() as all
parameters passed sanity checks, and after walking, we ended
up successfully at the chunk end boundary, and thus may invoke
sctp_process_asconf(). Parameter walking is done with
WORD_ROUND() to take padding into account.

In sctp_process_asconf()'s TLV processing, we may fail in
sctp_process_asconf_param() e.g., due to removal of the IP
address that is also the source address of the packet containing
the ASCONF chunk, and thus we need to add all TLVs after the
failure to our ASCONF response to remote via helper function
sctp_add_asconf_response(), which basically invokes a
sctp_addto_chunk() adding the error parameters to the given
skb.

When walking to the next parameter this time, we proceed
with ...

  length = ntohs(asconf_param->param_hdr.length);
  asconf_param = (void *)asconf_param + length;

... instead of the WORD_ROUND()'ed length, thus resulting here
in an off-by-one that leads to reading the follow-up garbage
parameter length of 12336, and thus throwing an skb_over_panic
for the reply when trying to sctp_addto_chunk() next time,
which implicitly calls the skb_put() with that length.

Fix it by using sctp_walk_params() [ which is also used in
INIT parameter processing ] macro in the verification *and*
in ASCONF processing: it will make sure we don't spill over,
that we walk parameters WORD_ROUND()'ed. Moreover, we're being
more defensive and guard against unknown parameter types and
missized addresses.

Joint work with Vlad Yasevich.

Fixes: b896b82be4ae ("[SCTP] ADDIP: Support for processing incoming ASCONF_ACK chunks.")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
net: sctp: fix panic on duplicate ASCONF chunks 2014-11-21T17:23:16+00:00 Daniel Borkmann dborkman@redhat.com 2014-10-09T20:55:32+00:00 dd8aaf1f380e008044857d7d2293e8e2824772b8 commit b69040d8e39f20d5215a03502a8e8b4c6ab78395 upstream. When receiving a e.g. semi-good formed connection scan in the form of ... -------------- INIT[ASCONF; ASCONF_ACK] -------------> <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------ -------------------- COOKIE-ECHO --------------------> <-------------------- COOKIE-ACK --------------------- ---------------- ASCONF_a; ASCONF_b -----------------> ... where ASCONF_a equals ASCONF_b chunk (at least both serials need to be equal), we panic an SCTP server! The problem is that good-formed ASCONF chunks that we reply with ASCONF_ACK chunks are cached per serial. Thus, when we receive a same ASCONF chunk twice (e.g. through a lost ASCONF_ACK), we do not need to process them again on the server side (that was the idea, also proposed in the RFC). Instead, we know it was cached and we just resend the cached chunk instead. So far, so good. Where things get nasty is in SCTP's side effect interpreter, that is, sctp_cmd_interpreter(): While incoming ASCONF_a (chunk = event_arg) is being marked !end_of_packet and !singleton, and we have an association context, we do not flush the outqueue the first time after processing the ASCONF_ACK singleton chunk via SCTP_CMD_REPLY. Instead, we keep it queued up, although we set local_cork to 1. Commit 2e3216cd54b1 changed the precedence, so that as long as we get bundled, incoming chunks we try possible bundling on outgoing queue as well. Before this commit, we would just flush the output queue. Now, while ASCONF_a's ASCONF_ACK sits in the corked outq, we continue to process the same ASCONF_b chunk from the packet. As we have cached the previous ASCONF_ACK, we find it, grab it and do another SCTP_CMD_REPLY command on it. So, effectively, we rip the chunk->list pointers and requeue the same ASCONF_ACK chunk another time. Since we process ASCONF_b, it's correctly marked with end_of_packet and we enforce an uncork, and thus flush, thus crashing the kernel. Fix it by testing if the ASCONF_ACK is currently pending and if that is the case, do not requeue it. When flushing the output queue we may relink the chunk for preparing an outgoing packet, but eventually unlink it when it's copied into the skb right before transmission. Joint work with Vlad Yasevich. Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet") Signed-off-by: Daniel Borkmann <dborkman@redhat.com> Signed-off-by: Vlad Yasevich <vyasevich@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net> Cc: Josh Boyer <jwboyer@fedoraproject.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit b69040d8e39f20d5215a03502a8e8b4c6ab78395 upstream.

When receiving a e.g. semi-good formed connection scan in the
form of ...

  -------------- INIT[ASCONF; ASCONF_ACK] ------------->
  <----------- INIT-ACK[ASCONF; ASCONF_ACK] ------------
  -------------------- COOKIE-ECHO -------------------->
  <-------------------- COOKIE-ACK ---------------------
  ---------------- ASCONF_a; ASCONF_b ----------------->

... where ASCONF_a equals ASCONF_b chunk (at least both serials
need to be equal), we panic an SCTP server!

The problem is that good-formed ASCONF chunks that we reply with
ASCONF_ACK chunks are cached per serial. Thus, when we receive a
same ASCONF chunk twice (e.g. through a lost ASCONF_ACK), we do
not need to process them again on the server side (that was the
idea, also proposed in the RFC). Instead, we know it was cached
and we just resend the cached chunk instead. So far, so good.

Where things get nasty is in SCTP's side effect interpreter, that
is, sctp_cmd_interpreter():

While incoming ASCONF_a (chunk = event_arg) is being marked
!end_of_packet and !singleton, and we have an association context,
we do not flush the outqueue the first time after processing the
ASCONF_ACK singleton chunk via SCTP_CMD_REPLY. Instead, we keep it
queued up, although we set local_cork to 1. Commit 2e3216cd54b1
changed the precedence, so that as long as we get bundled, incoming
chunks we try possible bundling on outgoing queue as well. Before
this commit, we would just flush the output queue.

Now, while ASCONF_a's ASCONF_ACK sits in the corked outq, we
continue to process the same ASCONF_b chunk from the packet. As
we have cached the previous ASCONF_ACK, we find it, grab it and
do another SCTP_CMD_REPLY command on it. So, effectively, we rip
the chunk->list pointers and requeue the same ASCONF_ACK chunk
another time. Since we process ASCONF_b, it's correctly marked
with end_of_packet and we enforce an uncork, and thus flush, thus
crashing the kernel.

Fix it by testing if the ASCONF_ACK is currently pending and if
that is the case, do not requeue it. When flushing the output
queue we may relink the chunk for preparing an outgoing packet,
but eventually unlink it when it's copied into the skb right
before transmission.

Joint work with Vlad Yasevich.

Fixes: 2e3216cd54b1 ("sctp: Follow security requirement of responding with 1 packet")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Vlad Yasevich <vyasevich@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Cc: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mm, thp: fix collapsing of hugepages on madvise 2014-11-21T17:23:15+00:00 David Rientjes rientjes@google.com 2014-10-29T21:50:31+00:00 1cc4ca2591fd14d2899dcf4f409a3f76febf9103 commit 6d50e60cd2edb5a57154db5a6f64eef5aa59b751 upstream. If an anonymous mapping is not allowed to fault thp memory and then madvise(MADV_HUGEPAGE) is used after fault, khugepaged will never collapse this memory into thp memory. This occurs because the madvise(2) handler for thp, hugepage_madvise(), clears VM_NOHUGEPAGE on the stack and it isn't stored in vma->vm_flags until the final action of madvise_behavior(). This causes the khugepaged_enter_vma_merge() to be a no-op in hugepage_madvise() when the vma had previously had VM_NOHUGEPAGE set. Fix this by passing the correct vma flags to the khugepaged mm slot handler. There's no chance khugepaged can run on this vma until after madvise_behavior() returns since we hold mm->mmap_sem. It would be possible to clear VM_NOHUGEPAGE directly from vma->vm_flags in hugepage_advise(), but I didn't want to introduce special case behavior into madvise_behavior(). I think it's best to just let it always set vma->vm_flags itself. Signed-off-by: David Rientjes <rientjes@google.com> Reported-by: Suleiman Souhlal <suleiman@google.com> Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 6d50e60cd2edb5a57154db5a6f64eef5aa59b751 upstream.

If an anonymous mapping is not allowed to fault thp memory and then
madvise(MADV_HUGEPAGE) is used after fault, khugepaged will never
collapse this memory into thp memory.

This occurs because the madvise(2) handler for thp, hugepage_madvise(),
clears VM_NOHUGEPAGE on the stack and it isn't stored in vma->vm_flags
until the final action of madvise_behavior().  This causes the
khugepaged_enter_vma_merge() to be a no-op in hugepage_madvise() when
the vma had previously had VM_NOHUGEPAGE set.

Fix this by passing the correct vma flags to the khugepaged mm slot
handler.  There's no chance khugepaged can run on this vma until after
madvise_behavior() returns since we hold mm->mmap_sem.

It would be possible to clear VM_NOHUGEPAGE directly from vma->vm_flags
in hugepage_advise(), but I didn't want to introduce special case
behavior into madvise_behavior().  I think it's best to just let it
always set vma->vm_flags itself.

Signed-off-by: David Rientjes <rientjes@google.com>
Reported-by: Suleiman Souhlal <suleiman@google.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
netfilter: xt_bpf: add mising opaque struct sk_filter definition 2014-11-21T17:23:15+00:00 Pablo Neira pablo@netfilter.org 2014-07-29T16:12:15+00:00 5aa67e1743992a470e8187dbb2e9bd3a66e385d0 commit e10038a8ec06ac819b7552bb67aaa6d2d6f850c1 upstream. This structure is not exposed to userspace, so fix this by defining struct sk_filter; so we skip the casting in kernelspace. This is safe since userspace has no way to lurk with that internal pointer. Fixes: e6f30c7 ("netfilter: x_tables: add xt_bpf match") Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e10038a8ec06ac819b7552bb67aaa6d2d6f850c1 upstream.

This structure is not exposed to userspace, so fix this by defining
struct sk_filter; so we skip the casting in kernelspace. This is safe
since userspace has no way to lurk with that internal pointer.

Fixes: e6f30c7 ("netfilter: x_tables: add xt_bpf match")
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
clocksource: Remove "weak" from clocksource_default_clock() declaration 2014-11-21T17:23:14+00:00 Bjorn Helgaas bhelgaas@google.com 2014-10-14T00:59:09+00:00 fefd9bdc44e64c55da24e2a7d96faaeb0d5aea1e commit 96a2adbc6f501996418da9f7afe39bf0e4d006a9 upstream. kernel/time/jiffies.c provides a default clocksource_default_clock() definition explicitly marked "weak". arch/s390 provides its own definition intended to override the default, but the "weak" attribute on the declaration applied to the s390 definition as well, so the linker chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node decl")). Remove the "weak" attribute from the clocksource_default_clock() declaration so we always prefer a non-weak definition over the weak one, independent of link order. Fixes: f1b82746c1e9 ("clocksource: Cleanup clocksource selection") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: John Stultz <john.stultz@linaro.org> Acked-by: Ingo Molnar <mingo@kernel.org> CC: Daniel Lezcano <daniel.lezcano@linaro.org> CC: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 96a2adbc6f501996418da9f7afe39bf0e4d006a9 upstream.

kernel/time/jiffies.c provides a default clocksource_default_clock()
definition explicitly marked "weak".  arch/s390 provides its own definition
intended to override the default, but the "weak" attribute on the
declaration applied to the s390 definition as well, so the linker chose one
based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from
pcibios_get_phb_of_node decl")).

Remove the "weak" attribute from the clocksource_default_clock()
declaration so we always prefer a non-weak definition over the weak one,
independent of link order.

Fixes: f1b82746c1e9 ("clocksource: Cleanup clocksource selection")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: John Stultz <john.stultz@linaro.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
CC: Daniel Lezcano <daniel.lezcano@linaro.org>
CC: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kgdb: Remove "weak" from kgdb_arch_pc() declaration 2014-11-21T17:23:14+00:00 Bjorn Helgaas bhelgaas@google.com 2014-10-14T01:00:25+00:00 401fc9d4842ecf2f5befd91ab0c92a126118e013 commit 107bcc6d566cb40184068d888637f9aefe6252dd upstream. kernel/debug/debug_core.c provides a default kgdb_arch_pc() definition explicitly marked "weak". Several architectures provide their own definitions intended to override the default, but the "weak" attribute on the declaration applied to the arch definitions as well, so the linker chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node decl")). Remove the "weak" attribute from the declaration so we always prefer a non-weak definition over the weak one, independent of link order. Fixes: 688b744d8bc8 ("kgdb: fix signedness mixmatches, add statics, add declaration to header") Tested-by: Vineet Gupta <vgupta@synopsys.com> # for ARC build Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Harvey Harrison <harvey.harrison@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 107bcc6d566cb40184068d888637f9aefe6252dd upstream.

kernel/debug/debug_core.c provides a default kgdb_arch_pc() definition
explicitly marked "weak".  Several architectures provide their own
definitions intended to override the default, but the "weak" attribute on
the declaration applied to the arch definitions as well, so the linker
chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak
annotation from pcibios_get_phb_of_node decl")).

Remove the "weak" attribute from the declaration so we always prefer a
non-weak definition over the weak one, independent of link order.

Fixes: 688b744d8bc8 ("kgdb: fix signedness mixmatches, add statics, add declaration to header")
Tested-by: Vineet Gupta <vgupta@synopsys.com>	# for ARC build
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
vmcore: Remove "weak" from function declarations 2014-11-21T17:23:14+00:00 Bjorn Helgaas bhelgaas@google.com 2014-10-14T00:59:41+00:00 0e46aef546ad5f89664fe09622b723117299b51d commit 5ab03ac5aaa1f032e071f1b3dc433b7839359c03 upstream. For the following functions: elfcorehdr_alloc() elfcorehdr_free() elfcorehdr_read() elfcorehdr_read_notes() remap_oldmem_pfn_range() fs/proc/vmcore.c provides default definitions explicitly marked "weak". arch/s390 provides its own definitions intended to override the default ones, but the "weak" attribute on the declarations applied to the s390 definitions as well, so the linker chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node decl")). Remove the "weak" attribute from the declarations so we always prefer a non-weak definition over the weak one, independent of link order. Fixes: be8a8d069e50 ("vmcore: introduce ELF header in new memory feature") Fixes: 9cb218131de1 ("vmcore: introduce remap_oldmem_pfn_range()") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Vivek Goyal <vgoyal@redhat.com> CC: Michael Holzheu <holzheu@linux.vnet.ibm.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 5ab03ac5aaa1f032e071f1b3dc433b7839359c03 upstream.

For the following functions:

  elfcorehdr_alloc()
  elfcorehdr_free()
  elfcorehdr_read()
  elfcorehdr_read_notes()
  remap_oldmem_pfn_range()

fs/proc/vmcore.c provides default definitions explicitly marked "weak".
arch/s390 provides its own definitions intended to override the default
ones, but the "weak" attribute on the declarations applied to the s390
definitions as well, so the linker chose one based on link order (see
10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node
decl")).

Remove the "weak" attribute from the declarations so we always prefer a
non-weak definition over the weak one, independent of link order.

Fixes: be8a8d069e50 ("vmcore: introduce ELF header in new memory feature")
Fixes: 9cb218131de1 ("vmcore: introduce remap_oldmem_pfn_range()")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
CC: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
memory-hotplug: Remove "weak" from memory_block_size_bytes() declaration 2014-11-21T17:23:14+00:00 Bjorn Helgaas bhelgaas@google.com 2014-10-14T01:00:47+00:00 6ba4331bc4ff1c4c0022d1efab4efb2ac582e561 commit e0a8400c6923a163265d52798cdd4c33f3f8ab5a upstream. drivers/base/memory.c provides a default memory_block_size_bytes() definition explicitly marked "weak". Several architectures provide their own definitions intended to override the default, but the "weak" attribute on the declaration applied to the arch definitions as well, so the linker chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak annotation from pcibios_get_phb_of_node decl")). Remove the "weak" attribute from the declaration so we always prefer a non-weak definition over the weak one, independent of link order. Fixes: 41f107266b19 ("drivers: base: Add prototype declaration to the header file") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> CC: Rashika Kheria <rashika.kheria@gmail.com> CC: Nathan Fontenot <nfont@austin.ibm.com> CC: Anton Blanchard <anton@au1.ibm.com> CC: Heiko Carstens <heiko.carstens@de.ibm.com> CC: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit e0a8400c6923a163265d52798cdd4c33f3f8ab5a upstream.

drivers/base/memory.c provides a default memory_block_size_bytes()
definition explicitly marked "weak".  Several architectures provide their
own definitions intended to override the default, but the "weak" attribute
on the declaration applied to the arch definitions as well, so the linker
chose one based on link order (see 10629d711ed7 ("PCI: Remove __weak
annotation from pcibios_get_phb_of_node decl")).

Remove the "weak" attribute from the declaration so we always prefer a
non-weak definition over the weak one, independent of link order.

Fixes: 41f107266b19 ("drivers: base: Add prototype declaration to the header file")
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Andrew Morton <akpm@linux-foundation.org>
CC: Rashika Kheria <rashika.kheria@gmail.com>
CC: Nathan Fontenot <nfont@austin.ibm.com>
CC: Anton Blanchard <anton@au1.ibm.com>
CC: Heiko Carstens <heiko.carstens@de.ibm.com>
CC: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
power: charger-manager: Fix accessing invalidated power supply after charger unbind 2014-11-21T17:23:13+00:00 Krzysztof Kozlowski k.kozlowski@samsung.com 2014-10-13T13:34:31+00:00 e5cb3367b6fde0c21983cf4deb38c9972a390c42 commit cdaf3e15385d3232b52287e50692506f8fd01a09 upstream. The charger manager obtained in probe references to power supplies for all chargers with power_supply_get_by_name() for later usage. However if such charger driver was removed then this reference would point to old power supply (from driver which was removed). This lead to accessing invalid memory which could be observed with: $ echo "max77693-charger" > /sys/bus/platform/drivers/max77693-charger/unbind $ grep . /sys/devices/virtual/power_supply/battery/charger.0/* $ grep . /sys/devices/virtual/power_supply/battery/* [ 15.339817] Unable to handle kernel paging request at virtual address 0001c12c [ 15.346187] pgd = edd08000 [ 15.348814] [0001c12c] *pgd=6dce2831, *pte=00000000, *ppte=00000000 [ 15.355075] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM [ 15.360967] Modules linked in: [ 15.364010] CPU: 2 PID: 1388 Comm: grep Not tainted 3.17.0-next-20141007-00027-ga95e761db1b0 #245 [ 15.372859] task: ee03ad00 ti: edcf6000 task.ti: edcf6000 [ 15.378241] PC is at 0x1c12c [ 15.381113] LR is at is_ext_pwr_online+0x30/0x6c [ 15.385706] pc : [<0001c12c>] lr : [<c0339fc4>] psr: a0000013 [ 15.385706] sp : edcf7e88 ip : 00000000 fp : 00000000 [ 15.397161] r10: eeb02c08 r9 : c04b1f84 r8 : eeb02c00 [ 15.402369] r7 : edc69a10 r6 : eea6ac10 r5 : eea6ac10 r4 : 00000004 [ 15.408878] r3 : 0001c12c r2 : edcf7e8c r1 : 00000004 r0 : ee914418 [ 15.415390] Flags: NzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 15.422506] Control: 10c5387d Table: 6dd0804a DAC: 00000015 [ 15.428236] Process grep (pid: 1388, stack limit = 0xedcf6240) [ 15.434050] Stack: (0xedcf7e88 to 0xedcf8000) [ 15.438395] 7e80: ee03ad00 00000000 edcf7f80 eea6aca8 edcf7ec4 c033b7b0 [ 15.446554] 7ea0: 00000001 ee1cc3f0 00000004 c06e1e44 eebdc000 c06e1e44 eeb02c00 c0337144 [ 15.454713] 7ec0: ee2dac68 c005cffc ee1cc3c0 c06e1e44 00000fff 00001000 eebdc000 c0278ca8 [ 15.462872] 7ee0: c0278c8c ee1cc3c0 eeb7ce00 c014422c edcf7f20 00008000 ee1cc3c0 ee9a48c0 [ 15.471030] 7f00: 00000001 00000001 edcf7f80 c0142d94 c0142d70 c01060f4 00021000 ee1cc3f0 [ 15.479190] 7f20: 00000000 00000000 c06a2150 eebdc000 2e7ec000 ee9a48c0 00008000 00021000 [ 15.487349] 7f40: edcf7f80 00008000 edcf6000 00021000 00021000 c00e39a4 00000000 ee9a48c0 [ 15.495508] 7f60: 00004000 00000000 00000000 ee9a48c0 ee9a48c0 00008000 00021000 c00e3aa0 [ 15.503668] 7f80: 00000000 00000000 0001f2e0 0001f2e0 00021000 00001000 00000003 c000f364 [ 15.511826] 7fa0: 00000000 c000f1a0 0001f2e0 00021000 00000003 00021000 00008000 00000000 [ 15.519986] 7fc0: 0001f2e0 00021000 00001000 00000003 00000001 000205e8 00000000 00021000 [ 15.528145] 7fe0: 00008000 bebbe910 0000a7ad b6edc49c 60000010 00000003 aaaaaaaa aaaaaaaa [ 15.536320] [<c0339fc4>] (is_ext_pwr_online) from [<c033b7b0>] (charger_get_property+0x170/0x314) [ 15.545164] [<c033b7b0>] (charger_get_property) from [<c0337144>] (power_supply_show_property+0x48/0x20c) [ 15.554719] [<c0337144>] (power_supply_show_property) from [<c0278ca8>] (dev_attr_show+0x1c/0x48) [ 15.563577] [<c0278ca8>] (dev_attr_show) from [<c014422c>] (sysfs_kf_seq_show+0x84/0x104) [ 15.571725] [<c014422c>] (sysfs_kf_seq_show) from [<c0142d94>] (kernfs_seq_show+0x24/0x28) [ 15.579973] [<c0142d94>] (kernfs_seq_show) from [<c01060f4>] (seq_read+0x1b0/0x484) [ 15.587614] [<c01060f4>] (seq_read) from [<c00e39a4>] (vfs_read+0x88/0x144) [ 15.594552] [<c00e39a4>] (vfs_read) from [<c00e3aa0>] (SyS_read+0x40/0x8c) [ 15.601417] [<c00e3aa0>] (SyS_read) from [<c000f1a0>] (ret_fast_syscall+0x0/0x48) [ 15.608877] Code: bad PC value [ 15.611991] ---[ end trace a88fcc95208db283 ]--- The charger-manager should get reference to charger power supply on each use of get_property callback. Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Fixes: 3bb3dbbd56ea ("power_supply: Add initial Charger-Manager driver") Signed-off-by: Sebastian Reichel <sre@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit cdaf3e15385d3232b52287e50692506f8fd01a09 upstream.

The charger manager obtained in probe references to power supplies for
all chargers with power_supply_get_by_name() for later usage. However
if such charger driver was removed then this reference would point to
old power supply (from driver which was removed).

This lead to accessing invalid memory which could be observed with:
$ echo "max77693-charger" > /sys/bus/platform/drivers/max77693-charger/unbind
$ grep . /sys/devices/virtual/power_supply/battery/charger.0/*
$ grep . /sys/devices/virtual/power_supply/battery/*
[   15.339817] Unable to handle kernel paging request at virtual address 0001c12c
[   15.346187] pgd = edd08000
[   15.348814] [0001c12c] *pgd=6dce2831, *pte=00000000, *ppte=00000000
[   15.355075] Internal error: Oops: 80000007 [#1] PREEMPT SMP ARM
[   15.360967] Modules linked in:
[   15.364010] CPU: 2 PID: 1388 Comm: grep Not tainted 3.17.0-next-20141007-00027-ga95e761db1b0 #245
[   15.372859] task: ee03ad00 ti: edcf6000 task.ti: edcf6000
[   15.378241] PC is at 0x1c12c
[   15.381113] LR is at is_ext_pwr_online+0x30/0x6c
[   15.385706] pc : [<0001c12c>]    lr : [<c0339fc4>]    psr: a0000013
[   15.385706] sp : edcf7e88  ip : 00000000  fp : 00000000
[   15.397161] r10: eeb02c08  r9 : c04b1f84  r8 : eeb02c00
[   15.402369] r7 : edc69a10  r6 : eea6ac10  r5 : eea6ac10  r4 : 00000004
[   15.408878] r3 : 0001c12c  r2 : edcf7e8c  r1 : 00000004  r0 : ee914418
[   15.415390] Flags: NzCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment user
[   15.422506] Control: 10c5387d  Table: 6dd0804a  DAC: 00000015
[   15.428236] Process grep (pid: 1388, stack limit = 0xedcf6240)
[   15.434050] Stack: (0xedcf7e88 to 0xedcf8000)
[   15.438395] 7e80:                   ee03ad00 00000000 edcf7f80 eea6aca8 edcf7ec4 c033b7b0
[   15.446554] 7ea0: 00000001 ee1cc3f0 00000004 c06e1e44 eebdc000 c06e1e44 eeb02c00 c0337144
[   15.454713] 7ec0: ee2dac68 c005cffc ee1cc3c0 c06e1e44 00000fff 00001000 eebdc000 c0278ca8
[   15.462872] 7ee0: c0278c8c ee1cc3c0 eeb7ce00 c014422c edcf7f20 00008000 ee1cc3c0 ee9a48c0
[   15.471030] 7f00: 00000001 00000001 edcf7f80 c0142d94 c0142d70 c01060f4 00021000 ee1cc3f0
[   15.479190] 7f20: 00000000 00000000 c06a2150 eebdc000 2e7ec000 ee9a48c0 00008000 00021000
[   15.487349] 7f40: edcf7f80 00008000 edcf6000 00021000 00021000 c00e39a4 00000000 ee9a48c0
[   15.495508] 7f60: 00004000 00000000 00000000 ee9a48c0 ee9a48c0 00008000 00021000 c00e3aa0
[   15.503668] 7f80: 00000000 00000000 0001f2e0 0001f2e0 00021000 00001000 00000003 c000f364
[   15.511826] 7fa0: 00000000 c000f1a0 0001f2e0 00021000 00000003 00021000 00008000 00000000
[   15.519986] 7fc0: 0001f2e0 00021000 00001000 00000003 00000001 000205e8 00000000 00021000
[   15.528145] 7fe0: 00008000 bebbe910 0000a7ad b6edc49c 60000010 00000003 aaaaaaaa aaaaaaaa
[   15.536320] [<c0339fc4>] (is_ext_pwr_online) from [<c033b7b0>] (charger_get_property+0x170/0x314)
[   15.545164] [<c033b7b0>] (charger_get_property) from [<c0337144>] (power_supply_show_property+0x48/0x20c)
[   15.554719] [<c0337144>] (power_supply_show_property) from [<c0278ca8>] (dev_attr_show+0x1c/0x48)
[   15.563577] [<c0278ca8>] (dev_attr_show) from [<c014422c>] (sysfs_kf_seq_show+0x84/0x104)
[   15.571725] [<c014422c>] (sysfs_kf_seq_show) from [<c0142d94>] (kernfs_seq_show+0x24/0x28)
[   15.579973] [<c0142d94>] (kernfs_seq_show) from [<c01060f4>] (seq_read+0x1b0/0x484)
[   15.587614] [<c01060f4>] (seq_read) from [<c00e39a4>] (vfs_read+0x88/0x144)
[   15.594552] [<c00e39a4>] (vfs_read) from [<c00e3aa0>] (SyS_read+0x40/0x8c)
[   15.601417] [<c00e3aa0>] (SyS_read) from [<c000f1a0>] (ret_fast_syscall+0x0/0x48)
[   15.608877] Code: bad PC value
[   15.611991] ---[ end trace a88fcc95208db283 ]---

The charger-manager should get reference to charger power supply on
each use of get_property callback.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 3bb3dbbd56ea ("power_supply: Add initial Charger-Manager driver")
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
power: charger-manager: Fix accessing invalidated power supply after fuel gauge unbind 2014-11-21T17:23:13+00:00 Krzysztof Kozlowski k.kozlowski@samsung.com 2014-10-13T13:34:30+00:00 767a001799421965635c7f524cde66ff34231701 commit bdbe81445407644492b9ac69a24d35e3202d773b upstream. The charger manager obtained reference to fuel gauge power supply in probe with power_supply_get_by_name() for later usage. However if fuel gauge driver was removed and re-added then this reference would point to old power supply (from driver which was removed). This lead to accessing old (and probably invalid) memory which could be observed with: $ echo "12-0036" > /sys/bus/i2c/drivers/max17042/unbind $ echo "12-0036" > /sys/bus/i2c/drivers/max17042/bind $ cat /sys/devices/virtual/power_supply/battery/capacity [ 240.480084] INFO: task cat:1393 blocked for more than 120 seconds. [ 240.484799] Not tainted 3.17.0-next-20141007-00028-ge60b6dd79570 #203 [ 240.491782] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [ 240.499589] cat D c0469530 0 1393 1 0x00000000 [ 240.505947] [<c0469530>] (__schedule) from [<c0469d3c>] (schedule_preempt_disabled+0x14/0x20) [ 240.514449] [<c0469d3c>] (schedule_preempt_disabled) from [<c046af08>] (mutex_lock_nested+0x1bc/0x458) [ 240.523736] [<c046af08>] (mutex_lock_nested) from [<c0287a98>] (regmap_read+0x30/0x60) [ 240.531647] [<c0287a98>] (regmap_read) from [<c032238c>] (max17042_get_property+0x2e8/0x350) [ 240.540055] [<c032238c>] (max17042_get_property) from [<c03247d8>] (charger_get_property+0x264/0x348) [ 240.549252] [<c03247d8>] (charger_get_property) from [<c0320764>] (power_supply_show_property+0x48/0x1e0) [ 240.558808] [<c0320764>] (power_supply_show_property) from [<c027308c>] (dev_attr_show+0x1c/0x48) [ 240.567664] [<c027308c>] (dev_attr_show) from [<c0141fb0>] (sysfs_kf_seq_show+0x84/0x104) [ 240.575814] [<c0141fb0>] (sysfs_kf_seq_show) from [<c0140b18>] (kernfs_seq_show+0x24/0x28) [ 240.584061] [<c0140b18>] (kernfs_seq_show) from [<c0104574>] (seq_read+0x1b0/0x484) [ 240.591702] [<c0104574>] (seq_read) from [<c00e1e24>] (vfs_read+0x88/0x144) [ 240.598640] [<c00e1e24>] (vfs_read) from [<c00e1f20>] (SyS_read+0x40/0x8c) [ 240.605507] [<c00e1f20>] (SyS_read) from [<c000e760>] (ret_fast_syscall+0x0/0x48) [ 240.612952] 4 locks held by cat/1393: [ 240.616589] #0: (&p->lock){+.+.+.}, at: [<c01043f4>] seq_read+0x30/0x484 [ 240.623414] #1: (&of->mutex){+.+.+.}, at: [<c01417dc>] kernfs_seq_start+0x1c/0x8c [ 240.631086] #2: (s_active#31){++++.+}, at: [<c01417e4>] kernfs_seq_start+0x24/0x8c [ 240.638777] #3: (&map->mutex){+.+...}, at: [<c0287a98>] regmap_read+0x30/0x60 The charger-manager should get reference to fuel gauge power supply on each use of get_property callback. The thermal zone 'tzd' field of power supply should not be used because of the same reason. Additionally this change solves also the issue with nested thermal_zone_get_temp() calls and related false lockdep positive for deadlock for thermal zone's mutex [1]. When fuel gauge is used as source of temperature then the charger manager forwards its get_temp calls to fuel gauge thermal zone. So actually different mutexes are used (one for charger manager thermal zone and second for fuel gauge thermal zone) but for lockdep this is one class of mutex. The recursion is removed by retrieving temperature through power supply's get_property(). In case external thermal zone is used ('cm-thermal-zone' property is present in DTS) the recursion does not exist. Charger manager simply exports POWER_SUPPLY_PROP_TEMP_AMBIENT property (instead of POWER_SUPPLY_PROP_TEMP) thus no thermal zone is created for this power supply. [1] https://lkml.org/lkml/2014/10/6/309 Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com> Fixes: 3bb3dbbd56ea ("power_supply: Add initial Charger-Manager driver") Signed-off-by: Sebastian Reichel <sre@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit bdbe81445407644492b9ac69a24d35e3202d773b upstream.

The charger manager obtained reference to fuel gauge power supply in probe
with power_supply_get_by_name() for later usage. However if fuel gauge
driver was removed and re-added then this reference would point to old
power supply (from driver which was removed).

This lead to accessing old (and probably invalid) memory which could be
observed with:
$ echo "12-0036" > /sys/bus/i2c/drivers/max17042/unbind
$ echo "12-0036" > /sys/bus/i2c/drivers/max17042/bind
$ cat /sys/devices/virtual/power_supply/battery/capacity
[  240.480084] INFO: task cat:1393 blocked for more than 120 seconds.
[  240.484799]       Not tainted 3.17.0-next-20141007-00028-ge60b6dd79570 #203
[  240.491782] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  240.499589] cat             D c0469530     0  1393      1 0x00000000
[  240.505947] [<c0469530>] (__schedule) from [<c0469d3c>] (schedule_preempt_disabled+0x14/0x20)
[  240.514449] [<c0469d3c>] (schedule_preempt_disabled) from [<c046af08>] (mutex_lock_nested+0x1bc/0x458)
[  240.523736] [<c046af08>] (mutex_lock_nested) from [<c0287a98>] (regmap_read+0x30/0x60)
[  240.531647] [<c0287a98>] (regmap_read) from [<c032238c>] (max17042_get_property+0x2e8/0x350)
[  240.540055] [<c032238c>] (max17042_get_property) from [<c03247d8>] (charger_get_property+0x264/0x348)
[  240.549252] [<c03247d8>] (charger_get_property) from [<c0320764>] (power_supply_show_property+0x48/0x1e0)
[  240.558808] [<c0320764>] (power_supply_show_property) from [<c027308c>] (dev_attr_show+0x1c/0x48)
[  240.567664] [<c027308c>] (dev_attr_show) from [<c0141fb0>] (sysfs_kf_seq_show+0x84/0x104)
[  240.575814] [<c0141fb0>] (sysfs_kf_seq_show) from [<c0140b18>] (kernfs_seq_show+0x24/0x28)
[  240.584061] [<c0140b18>] (kernfs_seq_show) from [<c0104574>] (seq_read+0x1b0/0x484)
[  240.591702] [<c0104574>] (seq_read) from [<c00e1e24>] (vfs_read+0x88/0x144)
[  240.598640] [<c00e1e24>] (vfs_read) from [<c00e1f20>] (SyS_read+0x40/0x8c)
[  240.605507] [<c00e1f20>] (SyS_read) from [<c000e760>] (ret_fast_syscall+0x0/0x48)
[  240.612952] 4 locks held by cat/1393:
[  240.616589]  #0:  (&p->lock){+.+.+.}, at: [<c01043f4>] seq_read+0x30/0x484
[  240.623414]  #1:  (&of->mutex){+.+.+.}, at: [<c01417dc>] kernfs_seq_start+0x1c/0x8c
[  240.631086]  #2:  (s_active#31){++++.+}, at: [<c01417e4>] kernfs_seq_start+0x24/0x8c
[  240.638777]  #3:  (&map->mutex){+.+...}, at: [<c0287a98>] regmap_read+0x30/0x60

The charger-manager should get reference to fuel gauge power supply on
each use of get_property callback. The thermal zone 'tzd' field of
power supply should not be used because of the same reason.

Additionally this change solves also the issue with nested
thermal_zone_get_temp() calls and related false lockdep positive for
deadlock for thermal zone's mutex [1]. When fuel gauge is used as source of
temperature then the charger manager forwards its get_temp calls to fuel
gauge thermal zone. So actually different mutexes are used (one for
charger manager thermal zone and second for fuel gauge thermal zone) but
for lockdep this is one class of mutex.

The recursion is removed by retrieving temperature through power
supply's get_property().

In case external thermal zone is used ('cm-thermal-zone' property is
present in DTS) the recursion does not exist. Charger manager simply
exports POWER_SUPPLY_PROP_TEMP_AMBIENT property (instead of
POWER_SUPPLY_PROP_TEMP) thus no thermal zone is created for this power
supply.

[1] https://lkml.org/lkml/2014/10/6/309

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Fixes: 3bb3dbbd56ea ("power_supply: Add initial Charger-Manager driver")
Signed-off-by: Sebastian Reichel <sre@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>