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Linux kernel
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For each device, the nosy driver allocates a pcilynx structure.
A use-after-free might happen in the following scenario:
1. Open nosy device for the first time and call ioctl with command
NOSY_IOC_START, then a new client A will be malloced and added to
doubly linked list.
2. Open nosy device for the second time and call ioctl with command
NOSY_IOC_START, then a new client B will be malloced and added to
doubly linked list.
3. Call ioctl with command NOSY_IOC_START for client A, then client A
will be readded to the doubly linked list. Now the doubly linked
list is messed up.
4. Close the first nosy device and nosy_release will be called. In
nosy_release, client A will be unlinked and freed.
5. Close the second nosy device, and client A will be referenced,
resulting in UAF.
The root cause of this bug is that the element in the doubly linked list
is reentered into the list.
Fix this bug by adding a check before inserting a client. If a client
is already in the linked list, don't insert it.
The following KASAN report reveals it:
BUG: KASAN: use-after-free in nosy_release+0x1ea/0x210
Write of size 8 at addr ffff888102ad7360 by task poc
CPU: 3 PID: 337 Comm: poc Not tainted 5.12.0-rc5+ #6
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
nosy_release+0x1ea/0x210
__fput+0x1e2/0x840
task_work_run+0xe8/0x180
exit_to_user_mode_prepare+0x114/0x120
syscall_exit_to_user_mode+0x1d/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
Allocated by task 337:
nosy_open+0x154/0x4d0
misc_open+0x2ec/0x410
chrdev_open+0x20d/0x5a0
do_dentry_open+0x40f/0xe80
path_openat+0x1cf9/0x37b0
do_filp_open+0x16d/0x390
do_sys_openat2+0x11d/0x360
__x64_sys_open+0xfd/0x1a0
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
Freed by task 337:
kfree+0x8f/0x210
nosy_release+0x158/0x210
__fput+0x1e2/0x840
task_work_run+0xe8/0x180
exit_to_user_mode_prepare+0x114/0x120
syscall_exit_to_user_mode+0x1d/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xae
The buggy address belongs to the object at ffff888102ad7300 which belongs to the cache kmalloc-128 of size 128
The buggy address is located 96 bytes inside of 128-byte region [ffff888102ad7300, ffff888102ad7380)
[ Modified to use 'list_empty()' inside proper lock - Linus ]
Link: https://lore.kernel.org/lkml/1617433116-5930-1-git-send-email-zheyuma97@gmail.com/
Reported-and-tested-by: 马哲宇 (Zheyu Ma) <zheyuma97@gmail.com>
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Cc: Greg Kroah-Hartman <greg@kroah.com>
Cc: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull OpenRISC fix from Stafford Horne:
"Fix duplicate header include in Litex SOC driver"
* tag 'for-linus' of git://github.com/openrisc/linux:
soc: litex: Remove duplicated header file inclusion
POull io_uring fix from Jens Axboe:
"Just fixing a silly braino in a previous patch, where we'd end up
failing to compile if CONFIG_BLOCK isn't enabled.
Not that a lot of people do that, but kernel bot spotted it and it's
probably prudent to just flush this out now before -rc6.
Sorry about that, none of my test compile configs have !CONFIG_BLOCK"
* tag 'io_uring-5.12-2021-04-03' of git://git.kernel.dk/linux-block:
io_uring: fix !CONFIG_BLOCK compilation failure
The header file <linux/errno.h> is already included above and can be
removed here.
Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Mateusz Holenko <mholenko@antmicro.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Pull gfs2 fixes from Andreas Gruenbacher:
"Two more gfs2 fixes"
* tag 'gfs2-v5.12-rc2-fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: report "already frozen/thawed" errors
gfs2: Flag a withdraw if init_threads() fails
kernel test robot correctly pinpoints a compilation failure if
CONFIG_BLOCK isn't set:
fs/io_uring.c: In function '__io_complete_rw':
>> fs/io_uring.c:2509:48: error: implicit declaration of function 'io_rw_should_reissue'; did you mean 'io_rw_reissue'? [-Werror=implicit-function-declaration]
2509 | if ((res == -EAGAIN || res == -EOPNOTSUPP) && io_rw_should_reissue(req)) {
| ^~~~~~~~~~~~~~~~~~~~
| io_rw_reissue
cc1: some warnings being treated as errors
Ensure that we have a stub declaration of io_rw_should_reissue() for
!CONFIG_BLOCK.
Fixes: 230d50d448ac ("io_uring: move reissue into regular IO path")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull RISC-V fixes from Palmer Dabbelt:
"A handful of fixes for 5.12:
- fix a stack tracing regression related to "const register asm"
variables, which have unexpected behavior.
- ensure the value to be written by put_user() is evaluated before
enabling access to userspace memory..
- align the exception vector table correctly, so we don't rely on the
firmware's handling of unaligned accesses.
- build fix to make NUMA depend on MMU, which triggered on some
randconfigs"
* tag 'riscv-for-linus-5.12-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Make NUMA depend on MMU
riscv: remove unneeded semicolon
riscv,entry: fix misaligned base for excp_vect_table
riscv: evaluate put_user() arg before enabling user access
riscv: Drop const annotation for sp
Before this patch, gfs2's freeze function failed to report an error
when the target file system was already frozen as it should (and as
generic vfs function freeze_super does. Similarly, gfs2's thaw function
failed to report an error when trying to thaw a file system that is not
frozen, as vfs function thaw_super does. The errors were checked, but
it always returned a 0 return code.
This patch adds the missing error return codes to gfs2 freeze and thaw.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
It's non-obvious how retry is done for block backed files, when it happens
off the kiocb done path. It also makes it tricky to deal with the iov_iter
handling.
Just mark the req as needing a reissue, and handling it from the
submission path instead. This makes it directly obvious that we're not
re-importing the iovec from userspace past the submit point, and it means
that we can just reuse our usual -EAGAIN retry path from the read/write
handling.
At some point in the future, we'll gain the ability to always reliably
return -EAGAIN through the stack. A previous attempt on the block side
didn't pan out and got reverted, hence the need to check for this
information out-of-band right now.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull perf tooling fixes from Arnaldo Carvalho de Melo:
- Avoid write of uninitialized memory when generating PERF_RECORD_MMAP*
records.
- Fix 'perf top' BPF support related crash with perf_event_paranoid=3 +
kptr_restrict.
- Validate raw event with sysfs exported format bits.
- Fix waipid on SIGCHLD delivery bugs in 'perf daemon'.
- Change to use bash for daemon test on Debian, where the default is
dash and thus fails for use of bashisms in this test.
- Fix memory leak in vDSO found using ASAN.
- Remove now useless (due to the fact that BPF now supports static
vars) failing sub test "BPF relocation checker".
- Fix auxtrace queue conflict.
- Sync linux/kvm.h with the kernel sources.
* tag 'perf-tools-fixes-for-v5.12-2020-03-28' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux:
perf test: Change to use bash for daemon test
perf record: Fix memory leak in vDSO found using ASAN
perf test: Remove now useless failing sub test "BPF relocation checker"
perf daemon: Return from kill functions
perf daemon: Force waipid for all session on SIGCHLD delivery
perf top: Fix BPF support related crash with perf_event_paranoid=3 + kptr_restrict
perf pmu: Validate raw event with sysfs exported format bits
perf synthetic events: Avoid write of uninitialized memory when generating PERF_RECORD_MMAP* records
tools headers UAPI: Sync linux/kvm.h with the kernel sources
perf synthetic-events: Fix uninitialized 'kernel_thread' variable
perf auxtrace: Fix auxtrace queue conflict
Pull powerpc fixes from Michael Ellerman:
"Fix a bug on pseries where spurious wakeups from H_PROD would prevent
partition migration from succeeding.
Fix oopses seen in pcpu_alloc(), caused by parallel faults of the
percpu mapping causing us to corrupt the protection key used for the
mapping, and cause a fatal key fault.
Thanks to Aneesh Kumar K.V, Murilo Opsfelder Araujo, and Nathan Lynch"
* tag 'powerpc-5.12-5' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
powerpc/mm/book3s64: Use the correct storage key value when calling H_PROTECT
powerpc/pseries/mobility: handle premature return from H_JOIN
powerpc/pseries/mobility: use struct for shared state
NUMA is useless when NOMMU, and it leads some build error,
make it depend on MMU.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
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