From: David Howells <dhowells@redhat.com>
To: linux-afs@lists.infradead.org
Cc: Tom Rix <trix@redhat.com>,
dhowells@redhat.com, Marc Dionne <marc.dionne@auristor.com>,
linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH v2 2/4] afs: check function return
Date: Mon, 12 Jul 2021 17:27:56 +0100 [thread overview]
Message-ID: <162610727640.3408253.8687445613469681311.stgit@warthog.procyon.org.uk> (raw)
In-Reply-To: <162610726011.3408253.2771348573083023654.stgit@warthog.procyon.org.uk>
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,
next prev parent reply other threads:[~2021-07-12 16:28 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-12 16:27 [PATCH v2 0/4] afs: Miscellaneous fixes David Howells
2021-07-12 16:27 ` [PATCH v2 1/4] afs: Fix tracepoint string placement with built-in AFS David Howells
2021-07-12 19:27 ` Marc Dionne
2021-07-12 16:27 ` David Howells [this message]
2021-07-21 12:59 ` [PATCH v2 2/4] afs: check function return Marc Dionne
2021-07-12 16:28 ` [PATCH v2 3/4] afs: Fix setting of writeback_index David Howells
2021-07-21 12:52 ` Marc Dionne
2021-07-12 16:28 ` [PATCH v2 4/4] afs: Remove redundant assignment to ret David Howells
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=162610727640.3408253.8687445613469681311.stgit@warthog.procyon.org.uk \
--to=dhowells@redhat.com \
--cc=linux-afs@lists.infradead.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=marc.dionne@auristor.com \
--cc=trix@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.