From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DF9A320314 for ; Wed, 15 May 2024 04:39:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715747996; cv=none; b=KFA7GPIabTY4O2tMRejZROMQYfi2E+ffcawkhf3NJ8qbyzJ7mpGJhq4aGZXdH/x2Knm/A1CA63U4B0kTVBDZOMYxmWG4OaPvGUV4IfU5sraAo6bJFavXyZ0IOYUXLVVx7xAxV2rttCRaXhFwb6OGrZ7aj4TDJfsw7eDcHaR2hbA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715747996; c=relaxed/simple; bh=n0yrT64pY/eVge12/E8DV4OoPeWlIcq/Yq63xC7LMjY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=TohUmZg5siS8hAr0HwXRELQJZ/YCyTMSi2g9CI3mPN3Eee2KnskIglouqp/adJabTEwddi4Z4kSJPMh/YzdhMfgPlb7tfCHMiEfwYfm8+LU40tpZ+P14guQzChZFsrdcbR2IYiezY7/cvpYKXT5b7QcQ3n7Nd4ljlotxWjpD2xo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=YqO18MEb; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="YqO18MEb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 256D2C116B1; Wed, 15 May 2024 04:39:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1715747995; bh=n0yrT64pY/eVge12/E8DV4OoPeWlIcq/Yq63xC7LMjY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=YqO18MEbKnnQtMQqoFFEvaB0VWPmTe1w/AFGlvhekCKgkPLEvr6XRWmTOSrLxuQVL GwxREmU8RLZXZ21BiqDqcE+PobhNTIFCSdQ/nKR8mdkDPkdG+XYyHjp56XXN+EAwQx v/ZrI3ZKImGp9hcd9KxUbwOSyA2saSmkJ/SCzRo8kl4W5I/1OC+rFDTUSHHn/grYzi pHbAX59J+FKyBg+rg8FGirdBelUOVRpupYriIPCxsP+GJR4bW2UsWtdyjUwgtkXaxr Pa94+V7ZSzPBkG/4ameLxtCmndfxopF5JbvoF/HBhGFIIshN1kprlWJDptn9YfXDbk Q+bw8o0aai58A== Date: Wed, 15 May 2024 04:39:53 +0000 From: Jaegeuk Kim To: Chao Yu Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, syzbot+848062ba19c8782ca5c8@syzkaller.appspotmail.com Subject: Re: [PATCH 3/3] f2fs: fix to do sanity check on i_nid for inline_data inode Message-ID: References: <20240506103313.773503-1-chao@kernel.org> <20240506103313.773503-3-chao@kernel.org> <948ecc86-63f5-48bb-b71c-61d57cbf446c@kernel.org> <02a4e80f-a146-4862-8399-3db42979b8fb@kernel.org> <43f128b0-5151-4ae6-9bc0-438c7a9871e9@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <43f128b0-5151-4ae6-9bc0-438c7a9871e9@kernel.org> On 05/15, Chao Yu wrote: > On 2024/5/15 0:07, Jaegeuk Kim wrote: > > 外部邮件/External Mail > > > > > > On 05/11, Chao Yu wrote: > > > On 2024/5/11 8:38, Jaegeuk Kim wrote: > > > > On 05/10, Chao Yu wrote: > > > > > On 2024/5/10 11:36, Jaegeuk Kim wrote: > > > > > > On 05/10, Chao Yu wrote: > > > > > > > On 2024/5/9 23:52, Jaegeuk Kim wrote: > > > > > > > > On 05/06, Chao Yu wrote: > > > > > > > > > syzbot reports a f2fs bug as below: > > > > > > > > > > > > > > > > > > ------------[ cut here ]------------ > > > > > > > > > kernel BUG at fs/f2fs/inline.c:258! > > > > > > > > > CPU: 1 PID: 34 Comm: kworker/u8:2 Not tainted 6.9.0-rc6-syzkaller-00012-g9e4bc4bcae01 #0 > > > > > > > > > RIP: 0010:f2fs_write_inline_data+0x781/0x790 fs/f2fs/inline.c:258 > > > > > > > > > Call Trace: > > > > > > > > > f2fs_write_single_data_page+0xb65/0x1d60 fs/f2fs/data.c:2834 > > > > > > > > > f2fs_write_cache_pages fs/f2fs/data.c:3133 [inline] > > > > > > > > > __f2fs_write_data_pages fs/f2fs/data.c:3288 [inline] > > > > > > > > > f2fs_write_data_pages+0x1efe/0x3a90 fs/f2fs/data.c:3315 > > > > > > > > > do_writepages+0x35b/0x870 mm/page-writeback.c:2612 > > > > > > > > > __writeback_single_inode+0x165/0x10b0 fs/fs-writeback.c:1650 > > > > > > > > > writeback_sb_inodes+0x905/0x1260 fs/fs-writeback.c:1941 > > > > > > > > > wb_writeback+0x457/0xce0 fs/fs-writeback.c:2117 > > > > > > > > > wb_do_writeback fs/fs-writeback.c:2264 [inline] > > > > > > > > > wb_workfn+0x410/0x1090 fs/fs-writeback.c:2304 > > > > > > > > > process_one_work kernel/workqueue.c:3254 [inline] > > > > > > > > > process_scheduled_works+0xa12/0x17c0 kernel/workqueue.c:3335 > > > > > > > > > worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 > > > > > > > > > kthread+0x2f2/0x390 kernel/kthread.c:388 > > > > > > > > > ret_from_fork+0x4d/0x80 arch/x86/kernel/process.c:147 > > > > > > > > > ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 > > > > > > > > > > > > > > > > > > The root cause is: inline_data inode can be fuzzed, so that there may > > > > > > > > > be valid blkaddr in its direct node, once f2fs triggers background GC > > > > > > > > > to migrate the block, it will hit f2fs_bug_on() during dirty page > > > > > > > > > writeback. > > > > > > > > > > > > > > > > > > Let's add sanity check on i_nid field for inline_data inode, meanwhile, > > > > > > > > > forbid to migrate inline_data inode's data block to fix this issue. > > > > > > > > > > > > > > > > > > Reported-by: syzbot+848062ba19c8782ca5c8@syzkaller.appspotmail.com > > > > > > > > > Closes: https://lore.kernel.org/linux-f2fs-devel/000000000000d103ce06174d7ec3@google.com > > > > > > > > > Signed-off-by: Chao Yu > > > > > > > > > --- > > > > > > > > > fs/f2fs/f2fs.h | 2 +- > > > > > > > > > fs/f2fs/gc.c | 6 ++++++ > > > > > > > > > fs/f2fs/inline.c | 17 ++++++++++++++++- > > > > > > > > > fs/f2fs/inode.c | 2 +- > > > > > > > > > 4 files changed, 24 insertions(+), 3 deletions(-) > > > > > > > > > > > > > > > > > > diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > > > > > > > > > index fced2b7652f4..c876813b5532 100644 > > > > > > > > > --- a/fs/f2fs/f2fs.h > > > > > > > > > +++ b/fs/f2fs/f2fs.h > > > > > > > > > @@ -4146,7 +4146,7 @@ extern struct kmem_cache *f2fs_inode_entry_slab; > > > > > > > > > * inline.c > > > > > > > > > */ > > > > > > > > > bool f2fs_may_inline_data(struct inode *inode); > > > > > > > > > -bool f2fs_sanity_check_inline_data(struct inode *inode); > > > > > > > > > +bool f2fs_sanity_check_inline_data(struct inode *inode, struct page *ipage); > > > > > > > > > bool f2fs_may_inline_dentry(struct inode *inode); > > > > > > > > > void f2fs_do_read_inline_data(struct page *page, struct page *ipage); > > > > > > > > > void f2fs_truncate_inline_inode(struct inode *inode, > > > > > > > > > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > > > > > > > > > index e86c7f01539a..041957750478 100644 > > > > > > > > > --- a/fs/f2fs/gc.c > > > > > > > > > +++ b/fs/f2fs/gc.c > > > > > > > > > @@ -1563,6 +1563,12 @@ static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > > > > > > > > > continue; > > > > > > > > > } > > > > > > > > > + if (f2fs_has_inline_data(inode)) { > > > > > > > > > + iput(inode); > > > > > > > > > + set_sbi_flag(sbi, SBI_NEED_FSCK); > > > > > > > > > + continue; > > > > > > > > > > > > > > > > Any race condtion to get this as false alarm? > > > > > > > > > > > > > > Since there is no reproducer for the bug, I doubt it was caused by metadata > > > > > > > fuzzing, something like this: > > > > > > > > > > > > > > - inline inode has one valid blkaddr in i_addr or in dnode reference by i_nid; > > > > > > > - SIT/SSA entry of the block is valid; > > > > > > > - background GC migrates the block; > > > > > > > - kworker writeback it, and trigger the bug_on(). > > > > > > > > > > > > Wasn't detected by sanity_check_inode? > > > > > > > > > > I fuzzed non-inline inode w/ below metadata fields: > > > > > - i_blocks = 1 > > > > > - i_size = 2048 > > > > > - i_inline |= 0x02 > > > > > > > > > > sanity_check_inode() doesn't complain. > > > > > > > > I mean, the below sanity_check_inode() can cover the fuzzed case? I'm wondering > > > > > > I didn't figure out a generic way in sanity_check_inode() to catch all fuzzed cases. > > > > > > The patch described: > > "The root cause is: inline_data inode can be fuzzed, so that there may > > be valid blkaddr in its direct node, once f2fs triggers background GC > > to migrate the block, it will hit f2fs_bug_on() during dirty page > > writeback." > > > > Do you suspect the node block address was suddenly assigned after f2fs_iget()? > > No, I suspect that the image was fuzzed by tools offline, not in runtime after > mount(). > > > Otherwise, it looks checking them in sanity_check_inode would be enough. > > > > > > > > e.g. > > > case #1 > > > - blkaddr, its dnode, SSA and SIT are consistent > > > - dnode.footer.ino points to inline inode > > > - inline inode doesn't link to the donde > > > > > > Something like fuzzed special file, please check details in below commit: > > > > > > 9056d6489f5a ("f2fs: fix to do sanity check on inode type during garbage collection") > > > > > > case #2 > > > - blkaddr, its dnode, SSA and SIT are consistent > > > - blkaddr locates in inline inode's i_addr > > The image status is something like above as I described. Then, why not just checking the gc path only? > > Thanks, > > > > > > > Thanks, > > > > > > > whether we really need to check it in the gc path. > > > > > > > > > > > > > > Thanks, > > > > > > > > > > > > > > > > > > > > > > > > > Thoughts? > > > > > > > > > > > > > > Thanks, > > > > > > > > > > > > > > > > > > > > > > > > + } > > > > > > > > > + > > > > > > > > > err = f2fs_gc_pinned_control(inode, gc_type, segno); > > > > > > > > > if (err == -EAGAIN) { > > > > > > > > > iput(inode); > > > > > > > > > diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c > > > > > > > > > index ac00423f117b..067600fed3d4 100644 > > > > > > > > > --- a/fs/f2fs/inline.c > > > > > > > > > +++ b/fs/f2fs/inline.c > > > > > > > > > @@ -33,11 +33,26 @@ bool f2fs_may_inline_data(struct inode *inode) > > > > > > > > > return !f2fs_post_read_required(inode); > > > > > > > > > } > > > > > > > > > -bool f2fs_sanity_check_inline_data(struct inode *inode) > > > > > > > > > +static bool has_node_blocks(struct inode *inode, struct page *ipage) > > > > > > > > > +{ > > > > > > > > > + struct f2fs_inode *ri = F2FS_INODE(ipage); > > > > > > > > > + int i; > > > > > > > > > + > > > > > > > > > + for (i = 0; i < DEF_NIDS_PER_INODE; i++) { > > > > > > > > > + if (ri->i_nid[i]) > > > > > > > > > + return true; > > > > > > > > > + } > > > > > > > > > + return false; > > > > > > > > > +} > > > > > > > > > + > > > > > > > > > +bool f2fs_sanity_check_inline_data(struct inode *inode, struct page *ipage) > > > > > > > > > { > > > > > > > > > if (!f2fs_has_inline_data(inode)) > > > > > > > > > return false; > > > > > > > > > + if (has_node_blocks(inode, ipage)) > > > > > > > > > + return false; > > > > > > > > > + > > > > > > > > > if (!support_inline_data(inode)) > > > > > > > > > return true; > > > > > > > > > diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c > > > > > > > > > index c26effdce9aa..1423cd27a477 100644 > > > > > > > > > --- a/fs/f2fs/inode.c > > > > > > > > > +++ b/fs/f2fs/inode.c > > > > > > > > > @@ -343,7 +343,7 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page) > > > > > > > > > } > > > > > > > > > } > > > > > > > > > - if (f2fs_sanity_check_inline_data(inode)) { > > > > > > > > > + if (f2fs_sanity_check_inline_data(inode, node_page)) { > > > > > > > > > f2fs_warn(sbi, "%s: inode (ino=%lx, mode=%u) should not have inline_data, run fsck to fix", > > > > > > > > > __func__, inode->i_ino, inode->i_mode); > > > > > > > > > return false; > > > > > > > > > -- > > > > > > > > > 2.40.1