| CVE |
Vendors |
Products |
Updated |
CVSS v3.1 |
| In the Linux kernel, the following vulnerability has been resolved:
usb: dwc3: core: Prevent USB core invalid event buffer address access
This commit addresses an issue where the USB core could access an
invalid event buffer address during runtime suspend, potentially causing
SMMU faults and other memory issues in Exynos platforms. The problem
arises from the following sequence.
1. In dwc3_gadget_suspend, there is a chance of a timeout when
moving the USB core to the halt state after clearing the
run/stop bit by software.
2. In dwc3_core_exit, the event buffer is cleared regardless of
the USB core's status, which may lead to an SMMU faults and
other memory issues. if the USB core tries to access the event
buffer address.
To prevent this hardware quirk on Exynos platforms, this commit ensures
that the event buffer address is not cleared by software when the USB
core is active during runtime suspend by checking its status before
clearing the buffer address. |
| In the Linux kernel, the following vulnerability has been resolved:
gpio: prevent potential speculation leaks in gpio_device_get_desc()
Userspace may trigger a speculative read of an address outside the gpio
descriptor array.
Users can do that by calling gpio_ioctl() with an offset out of range.
Offset is copied from user and then used as an array index to get
the gpio descriptor without sanitization in gpio_device_get_desc().
This change ensures that the offset is sanitized by using
array_index_nospec() to mitigate any possibility of speculative
information leaks.
This bug was discovered and resolved using Coverity Static Analysis
Security Testing (SAST) by Synopsys, Inc. |
| In the Linux kernel, the following vulnerability has been resolved:
dev/parport: fix the array out-of-bounds risk
Fixed array out-of-bounds issues caused by sprintf
by replacing it with snprintf for safer data copying,
ensuring the destination buffer is not overflowed.
Below is the stack trace I encountered during the actual issue:
[ 66.575408s] [pid:5118,cpu4,QThread,4]Kernel panic - not syncing: stack-protector:
Kernel stack is corrupted in: do_hardware_base_addr+0xcc/0xd0 [parport]
[ 66.575408s] [pid:5118,cpu4,QThread,5]CPU: 4 PID: 5118 Comm:
QThread Tainted: G S W O 5.10.97-arm64-desktop #7100.57021.2
[ 66.575439s] [pid:5118,cpu4,QThread,6]TGID: 5087 Comm: EFileApp
[ 66.575439s] [pid:5118,cpu4,QThread,7]Hardware name: HUAWEI HUAWEI QingYun
PGUX-W515x-B081/SP1PANGUXM, BIOS 1.00.07 04/29/2024
[ 66.575439s] [pid:5118,cpu4,QThread,8]Call trace:
[ 66.575469s] [pid:5118,cpu4,QThread,9] dump_backtrace+0x0/0x1c0
[ 66.575469s] [pid:5118,cpu4,QThread,0] show_stack+0x14/0x20
[ 66.575469s] [pid:5118,cpu4,QThread,1] dump_stack+0xd4/0x10c
[ 66.575500s] [pid:5118,cpu4,QThread,2] panic+0x1d8/0x3bc
[ 66.575500s] [pid:5118,cpu4,QThread,3] __stack_chk_fail+0x2c/0x38
[ 66.575500s] [pid:5118,cpu4,QThread,4] do_hardware_base_addr+0xcc/0xd0 [parport] |
| In the Linux kernel, the following vulnerability has been resolved:
mm: avoid overflows in dirty throttling logic
The dirty throttling logic is interspersed with assumptions that dirty
limits in PAGE_SIZE units fit into 32-bit (so that various multiplications
fit into 64-bits). If limits end up being larger, we will hit overflows,
possible divisions by 0 etc. Fix these problems by never allowing so
large dirty limits as they have dubious practical value anyway. For
dirty_bytes / dirty_background_bytes interfaces we can just refuse to set
so large limits. For dirty_ratio / dirty_background_ratio it isn't so
simple as the dirty limit is computed from the amount of available memory
which can change due to memory hotplug etc. So when converting dirty
limits from ratios to numbers of pages, we just don't allow the result to
exceed UINT_MAX.
This is root-only triggerable problem which occurs when the operator
sets dirty limits to >16 TB. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Take return from set_memory_ro() into account with bpf_prog_lock_ro()
set_memory_ro() can fail, leaving memory unprotected.
Check its return and take it into account as an error. |
| In the Linux kernel, the following vulnerability has been resolved:
bpf: Mark bpf prog stack with kmsan_unposion_memory in interpreter mode
syzbot reported uninit memory usages during map_{lookup,delete}_elem.
==========
BUG: KMSAN: uninit-value in __dev_map_lookup_elem kernel/bpf/devmap.c:441 [inline]
BUG: KMSAN: uninit-value in dev_map_lookup_elem+0xf3/0x170 kernel/bpf/devmap.c:796
__dev_map_lookup_elem kernel/bpf/devmap.c:441 [inline]
dev_map_lookup_elem+0xf3/0x170 kernel/bpf/devmap.c:796
____bpf_map_lookup_elem kernel/bpf/helpers.c:42 [inline]
bpf_map_lookup_elem+0x5c/0x80 kernel/bpf/helpers.c:38
___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997
__bpf_prog_run256+0xb5/0xe0 kernel/bpf/core.c:2237
==========
The reproducer should be in the interpreter mode.
The C reproducer is trying to run the following bpf prog:
0: (18) r0 = 0x0
2: (18) r1 = map[id:49]
4: (b7) r8 = 16777216
5: (7b) *(u64 *)(r10 -8) = r8
6: (bf) r2 = r10
7: (07) r2 += -229
^^^^^^^^^^
8: (b7) r3 = 8
9: (b7) r4 = 0
10: (85) call dev_map_lookup_elem#1543472
11: (95) exit
It is due to the "void *key" (r2) passed to the helper. bpf allows uninit
stack memory access for bpf prog with the right privileges. This patch
uses kmsan_unpoison_memory() to mark the stack as initialized.
This should address different syzbot reports on the uninit "void *key"
argument during map_{lookup,delete}_elem. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: strict bound check before memcmp in ocfs2_xattr_find_entry()
xattr in ocfs2 maybe 'non-indexed', which saved with additional space
requested. It's better to check if the memory is out of bound before
memcmp, although this possibility mainly comes from crafted poisonous
images. |
| In the Linux kernel, the following vulnerability has been resolved:
ocfs2: add bounds checking to ocfs2_check_dir_entry()
This adds sanity checks for ocfs2_dir_entry to make sure all members of
ocfs2_dir_entry don't stray beyond valid memory region. |
| In the Linux kernel, the following vulnerability has been resolved:
xfs: add bounds checking to xlog_recover_process_data
There is a lack of verification of the space occupied by fixed members
of xlog_op_header in the xlog_recover_process_data.
We can create a crafted image to trigger an out of bounds read by
following these steps:
1) Mount an image of xfs, and do some file operations to leave records
2) Before umounting, copy the image for subsequent steps to simulate
abnormal exit. Because umount will ensure that tail_blk and
head_blk are the same, which will result in the inability to enter
xlog_recover_process_data
3) Write a tool to parse and modify the copied image in step 2
4) Make the end of the xlog_op_header entries only 1 byte away from
xlog_rec_header->h_size
5) xlog_rec_header->h_num_logops++
6) Modify xlog_rec_header->h_crc
Fix:
Add a check to make sure there is sufficient space to access fixed members
of xlog_op_header. |
| In the Linux kernel, the following vulnerability has been resolved:
xfs: don't walk off the end of a directory data block
This adds sanity checks for xfs_dir2_data_unused and xfs_dir2_data_entry
to make sure don't stray beyond valid memory region. Before patching, the
loop simply checks that the start offset of the dup and dep is within the
range. So in a crafted image, if last entry is xfs_dir2_data_unused, we
can change dup->length to dup->length-1 and leave 1 byte of space. In the
next traversal, this space will be considered as dup or dep. We may
encounter an out of bound read when accessing the fixed members.
In the patch, we make sure that the remaining bytes large enough to hold
an unused entry before accessing xfs_dir2_data_unused and
xfs_dir2_data_unused is XFS_DIR2_DATA_ALIGN byte aligned. We also make
sure that the remaining bytes large enough to hold a dirent with a
single-byte name before accessing xfs_dir2_data_entry. |
| In the Linux kernel, the following vulnerability has been resolved:
drm/radeon: fix UBSAN warning in kv_dpm.c
Adds bounds check for sumo_vid_mapping_entry. |
| In the Linux kernel, the following vulnerability has been resolved:
scsi: qedi: Fix crash while reading debugfs attribute
The qedi_dbg_do_not_recover_cmd_read() function invokes sprintf() directly
on a __user pointer, which results into the crash.
To fix this issue, use a small local stack buffer for sprintf() and then
call simple_read_from_buffer(), which in turns make the copy_to_user()
call.
BUG: unable to handle page fault for address: 00007f4801111000
PGD 8000000864df6067 P4D 8000000864df6067 PUD 864df7067 PMD 846028067 PTE 0
Oops: 0002 [#1] PREEMPT SMP PTI
Hardware name: HPE ProLiant DL380 Gen10/ProLiant DL380 Gen10, BIOS U30 06/15/2023
RIP: 0010:memcpy_orig+0xcd/0x130
RSP: 0018:ffffb7a18c3ffc40 EFLAGS: 00010202
RAX: 00007f4801111000 RBX: 00007f4801111000 RCX: 000000000000000f
RDX: 000000000000000f RSI: ffffffffc0bfd7a0 RDI: 00007f4801111000
RBP: ffffffffc0bfd7a0 R08: 725f746f6e5f6f64 R09: 3d7265766f636572
R10: ffffb7a18c3ffd08 R11: 0000000000000000 R12: 00007f4881110fff
R13: 000000007fffffff R14: ffffb7a18c3ffca0 R15: ffffffffc0bfd7af
FS: 00007f480118a740(0000) GS:ffff98e38af00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f4801111000 CR3: 0000000864b8e001 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
<TASK>
? __die_body+0x1a/0x60
? page_fault_oops+0x183/0x510
? exc_page_fault+0x69/0x150
? asm_exc_page_fault+0x22/0x30
? memcpy_orig+0xcd/0x130
vsnprintf+0x102/0x4c0
sprintf+0x51/0x80
qedi_dbg_do_not_recover_cmd_read+0x2f/0x50 [qedi 6bcfdeeecdea037da47069eca2ba717c84a77324]
full_proxy_read+0x50/0x80
vfs_read+0xa5/0x2e0
? folio_add_new_anon_rmap+0x44/0xa0
? set_pte_at+0x15/0x30
? do_pte_missing+0x426/0x7f0
ksys_read+0xa5/0xe0
do_syscall_64+0x58/0x80
? __count_memcg_events+0x46/0x90
? count_memcg_event_mm+0x3d/0x60
? handle_mm_fault+0x196/0x2f0
? do_user_addr_fault+0x267/0x890
? exc_page_fault+0x69/0x150
entry_SYSCALL_64_after_hwframe+0x72/0xdc
RIP: 0033:0x7f4800f20b4d |
| In the Linux kernel, the following vulnerability has been resolved:
powerpc/pseries: Enforce hcall result buffer validity and size
plpar_hcall(), plpar_hcall9(), and related functions expect callers to
provide valid result buffers of certain minimum size. Currently this
is communicated only through comments in the code and the compiler has
no idea.
For example, if I write a bug like this:
long retbuf[PLPAR_HCALL_BUFSIZE]; // should be PLPAR_HCALL9_BUFSIZE
plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf, ...);
This compiles with no diagnostics emitted, but likely results in stack
corruption at runtime when plpar_hcall9() stores results past the end
of the array. (To be clear this is a contrived example and I have not
found a real instance yet.)
To make this class of error less likely, we can use explicitly-sized
array parameters instead of pointers in the declarations for the hcall
APIs. When compiled with -Warray-bounds[1], the code above now
provokes a diagnostic like this:
error: array argument is too small;
is of size 32, callee requires at least 72 [-Werror,-Warray-bounds]
60 | plpar_hcall9(H_ALLOCATE_VAS_WINDOW, retbuf,
| ^ ~~~~~~
[1] Enabled for LLVM builds but not GCC for now. See commit
0da6e5fd6c37 ("gcc: disable '-Warray-bounds' for gcc-13 too") and
related changes. |
| In the Linux kernel, the following vulnerability has been resolved:
jfs: xattr: fix buffer overflow for invalid xattr
When an xattr size is not what is expected, it is printed out to the
kernel log in hex format as a form of debugging. But when that xattr
size is bigger than the expected size, printing it out can cause an
access off the end of the buffer.
Fix this all up by properly restricting the size of the debug hex dump
in the kernel log. |
| In the Linux kernel, the following vulnerability has been resolved:
kdb: Fix buffer overflow during tab-complete
Currently, when the user attempts symbol completion with the Tab key, kdb
will use strncpy() to insert the completed symbol into the command buffer.
Unfortunately it passes the size of the source buffer rather than the
destination to strncpy() with predictably horrible results. Most obviously
if the command buffer is already full but cp, the cursor position, is in
the middle of the buffer, then we will write past the end of the supplied
buffer.
Fix this by replacing the dubious strncpy() calls with memmove()/memcpy()
calls plus explicit boundary checks to make sure we have enough space
before we start moving characters around. |
| In the Linux kernel, the following vulnerability has been resolved:
s390/ap: Fix crash in AP internal function modify_bitmap()
A system crash like this
Failing address: 200000cb7df6f000 TEID: 200000cb7df6f403
Fault in home space mode while using kernel ASCE.
AS:00000002d71bc007 R3:00000003fe5b8007 S:000000011a446000 P:000000015660c13d
Oops: 0038 ilc:3 [#1] PREEMPT SMP
Modules linked in: mlx5_ib ...
CPU: 8 PID: 7556 Comm: bash Not tainted 6.9.0-rc7 #8
Hardware name: IBM 3931 A01 704 (LPAR)
Krnl PSW : 0704e00180000000 0000014b75e7b606 (ap_parse_bitmap_str+0x10e/0x1f8)
R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:2 PM:0 RI:0 EA:3
Krnl GPRS: 0000000000000001 ffffffffffffffc0 0000000000000001 00000048f96b75d3
000000cb00000100 ffffffffffffffff ffffffffffffffff 000000cb7df6fce0
000000cb7df6fce0 00000000ffffffff 000000000000002b 00000048ffffffff
000003ff9b2dbc80 200000cb7df6fcd8 0000014bffffffc0 000000cb7df6fbc8
Krnl Code: 0000014b75e7b5fc: a7840047 brc 8,0000014b75e7b68a
0000014b75e7b600: 18b2 lr %r11,%r2
#0000014b75e7b602: a7f4000a brc 15,0000014b75e7b616
>0000014b75e7b606: eb22d00000e6 laog %r2,%r2,0(%r13)
0000014b75e7b60c: a7680001 lhi %r6,1
0000014b75e7b610: 187b lr %r7,%r11
0000014b75e7b612: 84960021 brxh %r9,%r6,0000014b75e7b654
0000014b75e7b616: 18e9 lr %r14,%r9
Call Trace:
[<0000014b75e7b606>] ap_parse_bitmap_str+0x10e/0x1f8
([<0000014b75e7b5dc>] ap_parse_bitmap_str+0xe4/0x1f8)
[<0000014b75e7b758>] apmask_store+0x68/0x140
[<0000014b75679196>] kernfs_fop_write_iter+0x14e/0x1e8
[<0000014b75598524>] vfs_write+0x1b4/0x448
[<0000014b7559894c>] ksys_write+0x74/0x100
[<0000014b7618a440>] __do_syscall+0x268/0x328
[<0000014b761a3558>] system_call+0x70/0x98
INFO: lockdep is turned off.
Last Breaking-Event-Address:
[<0000014b75e7b636>] ap_parse_bitmap_str+0x13e/0x1f8
Kernel panic - not syncing: Fatal exception: panic_on_oops
occured when /sys/bus/ap/a[pq]mask was updated with a relative mask value
(like +0x10-0x12,+60,-90) with one of the numeric values exceeding INT_MAX.
The fix is simple: use unsigned long values for the internal variables. The
correct checks are already in place in the function but a simple int for
the internal variables was used with the possibility to overflow. |
| In the Linux kernel, the following vulnerability has been resolved:
nfc: llcp: fix nfc_llcp_setsockopt() unsafe copies
syzbot reported unsafe calls to copy_from_sockptr() [1]
Use copy_safe_from_sockptr() instead.
[1]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in nfc_llcp_setsockopt+0x6c2/0x850 net/nfc/llcp_sock.c:255
Read of size 4 at addr ffff88801caa1ec3 by task syz-executor459/5078
CPU: 0 PID: 5078 Comm: syz-executor459 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
copy_from_sockptr include/linux/sockptr.h:55 [inline]
nfc_llcp_setsockopt+0x6c2/0x850 net/nfc/llcp_sock.c:255
do_sock_setsockopt+0x3b1/0x720 net/socket.c:2311
__sys_setsockopt+0x1ae/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xfd/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f7fac07fd89
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff660eb788 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f7fac07fd89
RDX: 0000000000000000 RSI: 0000000000000118 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000020000a80 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 |
| In the Linux kernel, the following vulnerability has been resolved:
btrfs: make sure that WRITTEN is set on all metadata blocks
We previously would call btrfs_check_leaf() if we had the check
integrity code enabled, which meant that we could only run the extended
leaf checks if we had WRITTEN set on the header flags.
This leaves a gap in our checking, because we could end up with
corruption on disk where WRITTEN isn't set on the leaf, and then the
extended leaf checks don't get run which we rely on to validate all of
the item pointers to make sure we don't access memory outside of the
extent buffer.
However, since 732fab95abe2 ("btrfs: check-integrity: remove
CONFIG_BTRFS_FS_CHECK_INTEGRITY option") we no longer call
btrfs_check_leaf() from btrfs_mark_buffer_dirty(), which means we only
ever call it on blocks that are being written out, and thus have WRITTEN
set, or that are being read in, which should have WRITTEN set.
Add checks to make sure we have WRITTEN set appropriately, and then make
sure __btrfs_check_leaf() always does the item checking. This will
protect us from file systems that have been corrupted and no longer have
WRITTEN set on some of the blocks.
This was hit on a crafted image tweaking the WRITTEN bit and reported by
KASAN as out-of-bound access in the eb accessors. The example is a dir
item at the end of an eb.
[2.042] BTRFS warning (device loop1): bad eb member start: ptr 0x3fff start 30572544 member offset 16410 size 2
[2.040] general protection fault, probably for non-canonical address 0xe0009d1000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI
[2.537] KASAN: maybe wild-memory-access in range [0x0005088000000018-0x000508800000001f]
[2.729] CPU: 0 PID: 2587 Comm: mount Not tainted 6.8.2 #1
[2.729] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
[2.621] RIP: 0010:btrfs_get_16+0x34b/0x6d0
[2.621] RSP: 0018:ffff88810871fab8 EFLAGS: 00000206
[2.621] RAX: 0000a11000000003 RBX: ffff888104ff8720 RCX: ffff88811b2288c0
[2.621] RDX: dffffc0000000000 RSI: ffffffff81dd8aca RDI: ffff88810871f748
[2.621] RBP: 000000000000401a R08: 0000000000000001 R09: ffffed10210e3ee9
[2.621] R10: ffff88810871f74f R11: 205d323430333737 R12: 000000000000001a
[2.621] R13: 000508800000001a R14: 1ffff110210e3f5d R15: ffffffff850011e8
[2.621] FS: 00007f56ea275840(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000
[2.621] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[2.621] CR2: 00007febd13b75c0 CR3: 000000010bb50000 CR4: 00000000000006f0
[2.621] Call Trace:
[2.621] <TASK>
[2.621] ? show_regs+0x74/0x80
[2.621] ? die_addr+0x46/0xc0
[2.621] ? exc_general_protection+0x161/0x2a0
[2.621] ? asm_exc_general_protection+0x26/0x30
[2.621] ? btrfs_get_16+0x33a/0x6d0
[2.621] ? btrfs_get_16+0x34b/0x6d0
[2.621] ? btrfs_get_16+0x33a/0x6d0
[2.621] ? __pfx_btrfs_get_16+0x10/0x10
[2.621] ? __pfx_mutex_unlock+0x10/0x10
[2.621] btrfs_match_dir_item_name+0x101/0x1a0
[2.621] btrfs_lookup_dir_item+0x1f3/0x280
[2.621] ? __pfx_btrfs_lookup_dir_item+0x10/0x10
[2.621] btrfs_get_tree+0xd25/0x1910
[ copy more details from report ] |
| In the Linux kernel, the following vulnerability has been resolved:
Squashfs: check the inode number is not the invalid value of zero
Syskiller has produced an out of bounds access in fill_meta_index().
That out of bounds access is ultimately caused because the inode
has an inode number with the invalid value of zero, which was not checked.
The reason this causes the out of bounds access is due to following
sequence of events:
1. Fill_meta_index() is called to allocate (via empty_meta_index())
and fill a metadata index. It however suffers a data read error
and aborts, invalidating the newly returned empty metadata index.
It does this by setting the inode number of the index to zero,
which means unused (zero is not a valid inode number).
2. When fill_meta_index() is subsequently called again on another
read operation, locate_meta_index() returns the previous index
because it matches the inode number of 0. Because this index
has been returned it is expected to have been filled, and because
it hasn't been, an out of bounds access is performed.
This patch adds a sanity check which checks that the inode number
is not zero when the inode is created and returns -EINVAL if it is.
[phillip@squashfs.org.uk: whitespace fix] |
| In the Linux kernel, the following vulnerability has been resolved:
block: Fix WARNING in _copy_from_iter
Syzkaller reports a warning in _copy_from_iter because an
iov_iter is supposedly used in the wrong direction. The reason
is that syzcaller managed to generate a request with
a transfer direction of SG_DXFER_TO_FROM_DEV. This instructs
the kernel to copy user buffers into the kernel, read into
the copied buffers and then copy the data back to user space.
Thus the iovec is used in both directions.
Detect this situation in the block layer and construct a new
iterator with the correct direction for the copy-in. |