| Message ID | 162610727640.3408253.8687445613469681311.stgit@warthog.procyon.org.uk (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | afs: Miscellaneous fixes | expand |
On Mon, Jul 12, 2021 at 1:28 PM David Howells <dhowells@redhat.com> wrote: > > From: Tom Rix <trix@redhat.com> > > Static analysis reports this problem > > write.c:773:29: warning: Assigned value is garbage or undefined > mapping->writeback_index = next; > ^ ~~~~ > The call to afs_writepages_region() can return without setting > next. So check the function return before using next. > > Changes: > ver #2: > - Need to fix the range_cyclic case also[1]. > > Fixes: e87b03f5830e ("afs: Prepare for use of THPs") > Signed-off-by: Tom Rix <trix@redhat.com> > Signed-off-by: David Howells <dhowells@redhat.com> > Link: https://lore.kernel.org/r/20210430155031.3287870-1-trix@redhat.com > Link: https://lore.kernel.org/r/162609464716.3133237.10354897554363093252.stgit@warthog.procyon.org.uk/ # v1 > Link: https://lore.kernel.org/r/CAB9dFdvHsLsw7CMnB+4cgciWDSqVjuij4mH3TaXnHQB8sz5rHw@mail.gmail.com/ [1] > --- > > fs/afs/write.c | 16 +++++++++++----- > 1 file changed, 11 insertions(+), 5 deletions(-) > > diff --git a/fs/afs/write.c b/fs/afs/write.c > index 3104b62c2082..1ed62e0ccfe5 100644 > --- a/fs/afs/write.c > +++ b/fs/afs/write.c > @@ -771,13 +771,19 @@ int afs_writepages(struct address_space *mapping, > if (wbc->range_cyclic) { > start = mapping->writeback_index * PAGE_SIZE; > ret = afs_writepages_region(mapping, wbc, start, LLONG_MAX, &next); > - if (start > 0 && wbc->nr_to_write > 0 && ret == 0) > - ret = afs_writepages_region(mapping, wbc, 0, start, > - &next); > - mapping->writeback_index = next / PAGE_SIZE; > + if (ret == 0) { > + mapping->writeback_index = next / PAGE_SIZE; > + if (start > 0 && wbc->nr_to_write > 0) { > + ret = afs_writepages_region(mapping, wbc, 0, > + start, &next); > + if (ret == 0) > + mapping->writeback_index = > + next / PAGE_SIZE; > + } > + } > } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) { > ret = afs_writepages_region(mapping, wbc, 0, LLONG_MAX, &next); > - if (wbc->nr_to_write > 0) > + if (wbc->nr_to_write > 0 && ret == 0) > mapping->writeback_index = next; > } else { > ret = afs_writepages_region(mapping, wbc, > > Reviewed-by: Marc Dionne <marc.dionne@auristor.com> Marc
diff --git a/fs/afs/write.c b/fs/afs/write.c index 3104b62c2082..1ed62e0ccfe5 100644 --- a/fs/afs/write.c +++ b/fs/afs/write.c @@ -771,13 +771,19 @@ int afs_writepages(struct address_space *mapping, if (wbc->range_cyclic) { start = mapping->writeback_index * PAGE_SIZE; ret = afs_writepages_region(mapping, wbc, start, LLONG_MAX, &next); - if (start > 0 && wbc->nr_to_write > 0 && ret == 0) - ret = afs_writepages_region(mapping, wbc, 0, start, - &next); - mapping->writeback_index = next / PAGE_SIZE; + if (ret == 0) { + mapping->writeback_index = next / PAGE_SIZE; + if (start > 0 && wbc->nr_to_write > 0) { + ret = afs_writepages_region(mapping, wbc, 0, + start, &next); + if (ret == 0) + mapping->writeback_index = + next / PAGE_SIZE; + } + } } else if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX) { ret = afs_writepages_region(mapping, wbc, 0, LLONG_MAX, &next); - if (wbc->nr_to_write > 0) + if (wbc->nr_to_write > 0 && ret == 0) mapping->writeback_index = next; } else { ret = afs_writepages_region(mapping, wbc,