Commit 72bb99cf authored Jul 22, 2013 by Karlis Ogsts Committed by Greg Kroah-Hartman Jul 23, 2013

staging: android: logger: Correct write offset reset on error



In the situation that a writer fails to copy data from userspace it will reset
the write offset to the value it had before it went to sleep. This discarding
any messages written while aquiring the mutex.

Therefore the reset offset needs to be retrieved after acquiring the mutex.

Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 644d4787

drivers/staging/android/logger.c

+3 −1

Original line number	Diff line number	Diff line
		@@ -469,7 +469,7 @@ static ssize_t logger_aio_write(struct kiocb iocb, const struct iovec iov,
		unsigned long nr_segs, loff_t ppos)
		{
		struct logger_log *log = file_get_log(iocb->ki_filp);
		size_t orig = log->w_off;
		size_t orig;
		struct logger_entry header;
		struct timespec now;
		ssize_t ret = 0;
		@@ -490,6 +490,8 @@ static ssize_t logger_aio_write(struct kiocb iocb, const struct iovec iov,

		mutex_lock(&log->mutex);

		orig = log->w_off;

		/*
		* Fix up any readers, pulling them forward to the first readable
		* entry after (what will be) the new write offset. We do this now