xavi/android_kernel_m2note/fs/direct-io.c, branch ng-7.1.2

direct-io: Prevent NULL pointer access in submit_page_section

2017-11-06T14:27:01+00:00

commit 899f0429c7d3eed886406cd72182bee3b96aa1f9 upstream. In the code added to function submit_page_section by commit b1058b981, sdio->bio can currently be NULL when calling dio_bio_submit. This then leads to a NULL pointer access in dio_bio_submit, so check for a NULL bio in submit_page_section before trying to submit it instead. Fixes xfstest generic/250 on gfs2. Cc: stable@vger.kernel.org # v3.10+ Signed-off-by: Andreas Gruenbacher Reviewed-by: Jan Kara Signed-off-by: Al Viro Signed-off-by: Willy Tarreau

leak in O_DIRECT readv past the EOF

2017-11-06T14:17:56+00:00

In all versions from 2.5.62 to 3.15, on each iteration through the loop by iovec array in do_blockdev_direct_IO() we used to do this: sdio.head = 0; sdio.tail = 0; ... retval = do_direct_IO(dio, &sdio, &map_bh); if (retval) { dio_cleanup(dio, &sdio); break; } with another dio_cleanup() done after the loop, catching the situation when retval had been 0. Consider the situation when e.g. the 3rd iovec in 4-iovec array passed to readv() has crossed the EOF. do_direct_IO() returns 0 and buggers off *without* exhausting the page array. The loop proceeds to the next iovec without calling dio_cleanup() and resets sdio.head and sdio.tail. That reset of sdio.{head,tail} has prevented the eventual dio_cleanup() from seeing anything and the page reference end up leaking. Commit 7b2c99d15559 (new helper: iov_iter_get_pages()) in 3.16 had eliminated the loop by iovec array, along with sdio.head and sdio.tail resets. Backporting that is too much work - the minimal fix is simply to make sure that the only case when do_direct_IO() buggers off early without returning non-zero will not skip dio_cleanup(). The fix applies to all versions from 2.5.62 to 3.15. Reported-and-tested-by: Venki Pallipadi Signed-off-by: Al Viro Signed-off-by: Willy Tarreau

misc: replace FUNCTION by function

2017-09-23T01:10:48+00:00

result of : git grep -l '__FUNCTION__' | xargs sed -i 's/__FUNCTION__/__func__/g'

non-ext4 portions of "direct-io: Implement generic deferred AIO completions"

2017-05-27T17:39:53+00:00

Originally from 7b7a8665edd8db73 Signed-off-by: Theodore Ts'o

first commit