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| author | Ali Ahmet Memis <ali@iusegentoo.com> | 2026-08-21 01:45:27 +0000 |
|---|---|---|
| committer | Stafford Horne <shorne@gmail.com> | 2026-08-29 07:32:26 +0100 |
| commit | 78004e9a87f240df03e2f73120d291763c32e0a7 (patch) | |
| tree | 137c22dd795222931b9d2bf2501d37cd766741aa /Documentation/ABI/testing/sysfs-driver-input-exc3000 | |
| download | linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.tar.gz linux-stable-78004e9a87f240df03e2f73120d291763c32e0a7.zip | |
openrisc: fix arbitrary kernel memory access via or1k_atomic syscallgrafted
sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user
pointers, v1 and v2, and swaps the words they point to in hand-written
assembly.
l.lwz r29,0(r4)
l.lwz r27,0(r5)
l.sw 0(r4),r27
l.sw 0(r5),r29
The pointers are not checked with access_ok(). The four memory
accesses also have no exception table entries.
A caller passes a kernel address as either pointer, and the syscall
reads from and writes to it directly.
This gives an unprivileged process a kernel read/write primitive. It
overwrites kernel data such as the sys_call_table, gaining code
execution in kernel context.
Check both pointers before entering the critical section. Add fixups
for the four memory accesses so faults on valid but unmapped user
addresses return -EFAULT.
[shorne@gmail.com: fix comment style]
Fixes: 9d02a4283e9c ("OpenRISC: Boot code")
Cc: stable@vger.kernel.org
Signed-off-by: Ali Ahmet Memis <ali@iusegentoo.com>
Signed-off-by: Stafford Horne <shorne@gmail.com>
Diffstat (limited to 'Documentation/ABI/testing/sysfs-driver-input-exc3000')
| -rw-r--r-- | Documentation/ABI/testing/sysfs-driver-input-exc3000 | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/Documentation/ABI/testing/sysfs-driver-input-exc3000 b/Documentation/ABI/testing/sysfs-driver-input-exc3000 new file mode 100644 index 000000000..704434b27 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-input-exc3000 @@ -0,0 +1,26 @@ +What: /sys/bus/i2c/devices/xxx/fw_version +Date: Aug 2020 +Contact: linux-input@vger.kernel.org +Description: Reports the firmware version provided by the touchscreen, for example "00_T6" on a EXC80H60 + + Access: Read + + Valid values: Represented as string + +What: /sys/bus/i2c/devices/xxx/model +Date: Aug 2020 +Contact: linux-input@vger.kernel.org +Description: Reports the model identification provided by the touchscreen, for example "Orion_1320" on a EXC80H60 + + Access: Read + + Valid values: Represented as string + +What: /sys/bus/i2c/devices/xxx/type +Date: Jan 2021 +Contact: linux-input@vger.kernel.org +Description: Reports the type identification provided by the touchscreen, for example "PCAP82H80 Series" + + Access: Read + + Valid values: Represented as string |