This is a note to let you know that I've just added the patch titled
tools: iio: iio_generic_buffer: Fix read size
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tools-iio-iio_generic_buffer-fix-read-size.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e0a262bde3d071c82909ebedd0fc9c0b1f8cf75d
Author: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
Date: Fri Oct 14 10:15:19 2022 +0300
tools: iio: iio_generic_buffer: Fix read size
[ Upstream commit 7c919b619bcc68158921b1bd968f0e704549bbb6 ]
When noevents is true and small buffer is used the allocated memory for
holding the data may be smaller than the hard-coded 64 bytes. This can
cause the iio_generic_buffer to crash.
Following was recorded on beagle bone black with v6.0 kernel and the
digit fix patch:
https://lore.kernel.org/all/Y0f+tKCz+ZAIoroQ@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/
using valgrind;
==339== Using Valgrind-3.18.1 and LibVEX; rerun with -h for copyright info
==339== Command: /iio_generic_buffer -n kx022-accel -T0 -e -l 10 -a -w 2000000
==339== Parent PID: 307
==339==
==339== Syscall param read(buf) points to unaddressable byte(s)
==339== at 0x496BFA4: read (read.c:26)
==339== by 0x11699: main (iio_generic_buffer.c:724)
==339== Address 0x4ab3518 is 0 bytes after a block of size 160 alloc'd
==339== at 0x4864B70: malloc (vg_replace_malloc.c:381)
==339== by 0x115BB: main (iio_generic_buffer.c:677)
Fix this by always using the same size for reading as was used for
data storage allocation.
Signed-off-by: Matti Vaittinen <mazziesaccount@xxxxxxxxx>
Link: https://lore.kernel.org/r/Y0kMh0t5qUXJw3nQ@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/iio/iio_generic_buffer.c b/tools/iio/iio_generic_buffer.c
index 2491c54a5e4f..f8deae4e26a1 100644
--- a/tools/iio/iio_generic_buffer.c
+++ b/tools/iio/iio_generic_buffer.c
@@ -715,12 +715,12 @@ int main(int argc, char **argv)
continue;
}
- toread = buf_len;
} else {
usleep(timedelay);
- toread = 64;
}
+ toread = buf_len;
+
read_size = read(buf_fd, data, toread * scan_size);
if (read_size < 0) {
if (errno == EAGAIN) {
