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Linux kernel
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several of them using the Restructured Text markup notation.
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the problems which may result by upgrading your kernel.
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Pull arm64 fixes from Will Deacon:
"Although we're still debugging a few minor arm64-specific issues in
mainline, I didn't want to hold this lot up in the meantime.
We've got an additional KASLR fix after the previous one wasn't quite
complete, a fix for a performance regression when mapping executable
pages into userspace and some fixes for kprobe blacklisting. All
candidates for stable.
Summary:
- Fix module loading when KASLR is configured but disabled at runtime
- Fix accidental IPI when mapping user executable pages
- Ensure hyp-stub and KVM world switch code cannot be kprobed"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
arm64: hibernate: Clean the __hyp_text to PoC after resume
arm64: hyp-stub: Forbid kprobing of the hyp-stub
arm64: kprobe: Always blacklist the KVM world-switch code
arm64: kaslr: ensure randomized quantities are clean also when kaslr is off
arm64: Do not issue IPIs for user executable ptes
Pull smb3 fixes from Steve French:
"SMB3 fixes, some from this week's SMB3 test evemt, 5 for stable and a
particularly important one for queryxattr (see xfstests 70 and 117)"
* tag '5.0-rc4-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: update internal module version number
CIFS: fix use-after-free of the lease keys
CIFS: Do not consider -ENODATA as stat failure for reads
CIFS: Do not count -ENODATA as failure for query directory
CIFS: Fix trace command logging for SMB2 reads and writes
CIFS: Fix possible oops and memory leaks in async IO
cifs: limit amount of data we request for xattrs to CIFSMaxBufSize
cifs: fix computation for MAX_SMB2_HDR_SIZE
During resume hibernate restores all physical memory. Any memory
that is accessed with the MMU disabled needs to be cleaned to the
PoC.
KVMs __hyp_text was previously ommitted as it runs with the MMU
enabled, but now that the hyp-stub is located in this section,
we must clean __hyp_text too.
This ensures secondary CPUs that come online after hibernate
has finished resuming, and load KVM via the freshly written
hyp-stub see the correct instructions.
Signed-off-by: James Morse <james.morse@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
Pull apparmor bug fixes from John Johansen:
"Two bug fixes for apparmor:
- Fix aa_label_build() error handling for failed merges
- Fix warning about unused function apparmor_ipv6_postroute"
* tag 'apparmor-pr-2019-02-01' of git://git.kernel.org/pub/scm/linux/kernel/git/jj/linux-apparmor:
apparmor: Fix aa_label_build() error handling for failed merges
apparmor: Fix warning about unused function apparmor_ipv6_postroute
To 2.17
Signed-off-by: Steve French <stfrench@microsoft.com>
The hyp-stub is loaded by the kernel's early startup code at EL2
during boot, before KVM takes ownership later. The hyp-stub's
text is part of the regular kernel text, meaning it can be kprobed.
A breakpoint in the hyp-stub causes the CPU to spin in el2_sync_invalid.
Add it to the __hyp_text.
Signed-off-by: James Morse <james.morse@arm.com>
Cc: stable@vger.kernel.org
Signed-off-by: Will Deacon <will.deacon@arm.com>
Pull rdma fixes from Jason Gunthorpe:
"Still not much going on, the usual set of oops and driver fixes this
time:
- Fix two uapi breakage regressions in mlx5 drivers
- Various oops fixes in hfi1, mlx4, umem, uverbs, and ipoib
- A protocol bug fix for hfi1 preventing it from implementing the
verbs API properly, and a compatability fix for EXEC STACK user
programs
- Fix missed refcounting in the 'advise_mr' patches merged this
cycle.
- Fix wrong use of the uABI in the hns SRQ patches merged this cycle"
* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
IB/uverbs: Fix OOPs in uverbs_user_mmap_disassociate
IB/ipoib: Fix for use-after-free in ipoib_cm_tx_start
IB/uverbs: Fix ioctl query port to consider device disassociation
RDMA/mlx5: Fix flow creation on representors
IB/uverbs: Fix OOPs upon device disassociation
RDMA/umem: Add missing initialization of owning_mm
RDMA/hns: Update the kernel header file of hns
IB/mlx5: Fix how advise_mr() launches async work
RDMA/device: Expose ib_device_try_get(()
IB/hfi1: Add limit test for RC/UC send via loopback
IB/hfi1: Remove overly conservative VM_EXEC flag check
IB/{hfi1, qib}: Fix WC.byte_len calculation for UD_SEND_WITH_IMM
IB/mlx4: Fix using wrong function to destroy sqp AHs under SRIOV
RDMA/mlx5: Fix check for supported user flags when creating a QP
aa_label_merge() can return NULL for memory allocations failures
make sure to handle and set the correct error in this case.
Reported-by: Peng Hao <peng.hao2@zte.com.cn>
Signed-off-by: John Johansen <john.johansen@canonical.com>
The request buffers are freed right before copying the pointers.
Use the func args instead which are identical and still valid.
Simple reproducer (requires KASAN enabled) on a cifs mount:
echo foo > foo ; tail -f foo & rm foo
Cc: <stable@vger.kernel.org> # 4.20
Fixes: 179e44d49c2f ("smb3: add tracepoint for sending lease break responses to server")
Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.de>
On systems with VHE the kernel and KVM's world-switch code run at the
same exception level. Code that is only used on a VHE system does not
need to be annotated as __hyp_text as it can reside anywhere in the
kernel text.
__hyp_text was also used to prevent kprobes from patching breakpoint
instructions into this region, as this code runs at a different
exception level. While this is no longer true with VHE, KVM still
switches VBAR_EL1, meaning a kprobe's breakpoint executed in the
world-switch code will cause a hyp-panic.
Move the __hyp_text check in the kprobes blacklist so it applies on
VHE systems too, to cover the common code and guest enter/exit
assembly.
Fixes: 888b3c8720e0 ("arm64: Treat all entry code as non-kprobe-able")
Reviewed-by: Christoffer Dall <christoffer.dall@arm.com>
Signed-off-by: James Morse <james.morse@arm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Pull iomap fixes from Darrick Wong:
"A couple of iomap fixes to eliminate some memory corruption and hang
problems that were reported:
- fix page migration when using iomap for pagecache management
- fix a use-after-free bug in the directio code"
* tag 'iomap-5.0-fixes-1' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
iomap: fix a use after free in iomap_dio_rw
iomap: get/put the page in iomap_page_create/release()
The vma->vm_mm can become impossible to get before rdma_umap_close() is
called, in this case we must not try to get an mm that is already
undergoing process exit. In this case there is no need to wait for
anything as the VMA will be destroyed by another thread soon and is
already effectively 'unreachable' by userspace.
BUG: unable to handle kernel NULL pointer dereference at 0000000000000000
PGD 800000012bc50067 P4D 800000012bc50067 PUD 129db5067 PMD 0
Oops: 0000 [#1] SMP PTI
CPU: 1 PID: 2050 Comm: bash Tainted: G W OE 4.20.0-rc6+ #3
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
RIP: 0010:__rb_erase_color+0xb9/0x280
Code: 84 17 01 00 00 48 3b 68 10 0f 84 15 01 00 00 48 89
58 08 48 89 de 48 89 ef 4c 89 e3 e8 90 84 22 00 e9 60 ff ff ff 48 8b 5d
10 <f6> 03 01 0f 84 9c 00 00 00 48 8b 43 10 48 85 c0 74 09 f6 00 01 0f
RSP: 0018:ffffbecfc090bab8 EFLAGS: 00010246
RAX: ffff97616346cf30 RBX: 0000000000000000 RCX: 0000000000000101
RDX: 0000000000000000 RSI: ffff97623b6ca828 RDI: ffff97621ef10828
RBP: ffff97621ef10828 R08: ffff97621ef10828 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffff97623b6ca838
R13: ffffffffbb3fef50 R14: ffff97623b6ca828 R15: 0000000000000000
FS: 00007f7a5c31d740(0000) GS:ffff97623bb00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000011255a000 CR4: 00000000000006e0
Call Trace:
unlink_file_vma+0x3b/0x50
free_pgtables+0xa1/0x110
exit_mmap+0xca/0x1a0
? mlx5_ib_dealloc_pd+0x28/0x30 [mlx5_ib]
mmput+0x54/0x140
uverbs_user_mmap_disassociate+0xcc/0x160 [ib_uverbs]
uverbs_destroy_ufile_hw+0xf7/0x120 [ib_uverbs]
ib_uverbs_remove_one+0xea/0x240 [ib_uverbs]
ib_unregister_device+0xfb/0x200 [ib_core]
mlx5_ib_remove+0x51/0xe0 [mlx5_ib]
mlx5_remove_device+0xc1/0xd0 [mlx5_core]
mlx5_unregister_device+0x3d/0xb0 [mlx5_core]
remove_one+0x2a/0x90 [mlx5_core]
pci_device_remove+0x3b/0xc0
device_release_driver_internal+0x16d/0x240
unbind_store+0xb2/0x100
kernfs_fop_write+0x102/0x180
__vfs_write+0x36/0x1a0
? __alloc_fd+0xa9/0x170
? set_close_on_exec+0x49/0x70
vfs_write+0xad/0x1a0
ksys_write+0x52/0xc0
do_syscall_64+0x5b/0x180
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Cc: <stable@vger.kernel.org> # 4.19
Fixes: 5f9794dc94f5 ("RDMA/ucontext: Add a core API for mmaping driver IO memory")
Signed-off-by: Yishai Hadas <yishaih@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
when compiled without CONFIG_IPV6:
security/apparmor/lsm.c:1601:21: warning: ‘apparmor_ipv6_postroute’ defined but not used [-Wunused-function]
static unsigned int apparmor_ipv6_postroute(void *priv,
^~~~~~~~~~~~~~~~~~~~~~~
Reported-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Tested-by: Jordan Glover <Golden_Miller83@protonmail.ch>
Signed-off-by: Petr Vorel <pvorel@suse.cz>
Signed-off-by: John Johansen <john.johansen@canonical.com>
When doing reads beyound the end of a file the server returns
error STATUS_END_OF_FILE error which is mapped to -ENODATA.
Currently we report it as a failure which confuses read stats.
Change it to not consider -ENODATA as failure for stat purposes.
Signed-off-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
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