diff mbox series

staging: erofs: fix an error handling in erofs_readdir()

Message ID 20190818031855.9723-1-hsiangkao@aol.com (mailing list archive)
State New, archived
Headers show
Series staging: erofs: fix an error handling in erofs_readdir() | expand

Commit Message

Gao Xiang Aug. 18, 2019, 3:18 a.m. UTC
From: Gao Xiang <gaoxiang25@huawei.com>

Richard observed a forever loop of erofs_read_raw_page() [1]
which can be generated by forcely setting ->u.i_blkaddr
to 0xdeadbeef (as my understanding block layer can
handle access beyond end of device correctly).

After digging into that, it seems the problem is highly
related with directories and then I found the root cause
is an improper error handling in erofs_readdir().

Let's fix it now.

[1] https://lore.kernel.org/r/1163995781.68824.1566084358245.JavaMail.zimbra@nod.at/

Reported-by: Richard Weinberger <richard@nod.at>
Fixes: 3aa8ec716e52 ("staging: erofs: add directory operations")
Cc: <stable@vger.kernel.org> # 4.19+
Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
---
changelog from v2:
 - transform EIO to EFSCORRUPTED as suggested by Matthew;

changelog from v1:
 - fix the incorrect external link in commit message.

This patch is based on the following patch as well
https://lore.kernel.org/r/20190816071142.8633-1-gaoxiang25@huawei.com/

and
https://lore.kernel.org/r/20190817082313.21040-1-hsiangkao@aol.com/
can still be properly applied after this patch.

 drivers/staging/erofs/dir.c | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

Comments

Gao Xiang Aug. 18, 2019, 1:25 p.m. UTC | #1
On Sun, Aug 18, 2019 at 09:17:52PM +0800, kbuild test robot wrote:
> Hi Gao,
> 
> I love your patch! Yet something to improve:
> 
> [auto build test ERROR on linus/master]
> [cannot apply to v5.3-rc4 next-20190816]
> [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

... those patches should be applied to staging tree
since linux-next has not been updated yet...

Thanks,
Gao Xiang

> 
> url:    https://github.com/0day-ci/linux/commits/Gao-Xiang/staging-erofs-fix-an-error-handling-in-erofs_readdir/20190818-191344
> config: arm64-allyesconfig (attached as .config)
> compiler: aarch64-linux-gcc (GCC) 7.4.0
> reproduce:
>         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
>         chmod +x ~/bin/make.cross
>         # save the attached .config to linux build tree
>         GCC_VERSION=7.4.0 make.cross ARCH=arm64 
> 
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <lkp@intel.com>
> 
> All errors (new ones prefixed by >>):
> 
>    drivers/staging/erofs/dir.c: In function 'erofs_readdir':
> >> drivers/staging/erofs/dir.c:110:11: error: 'EFSCORRUPTED' undeclared (first use in this function); did you mean 'FS_NRSUPER'?
>        err = -EFSCORRUPTED;
>               ^~~~~~~~~~~~
>               FS_NRSUPER
>    drivers/staging/erofs/dir.c:110:11: note: each undeclared identifier is reported only once for each function it appears in
> 
> vim +110 drivers/staging/erofs/dir.c
> 
>     85	
>     86	static int erofs_readdir(struct file *f, struct dir_context *ctx)
>     87	{
>     88		struct inode *dir = file_inode(f);
>     89		struct address_space *mapping = dir->i_mapping;
>     90		const size_t dirsize = i_size_read(dir);
>     91		unsigned int i = ctx->pos / EROFS_BLKSIZ;
>     92		unsigned int ofs = ctx->pos % EROFS_BLKSIZ;
>     93		int err = 0;
>     94		bool initial = true;
>     95	
>     96		while (ctx->pos < dirsize) {
>     97			struct page *dentry_page;
>     98			struct erofs_dirent *de;
>     99			unsigned int nameoff, maxsize;
>    100	
>    101			dentry_page = read_mapping_page(mapping, i, NULL);
>    102			if (dentry_page == ERR_PTR(-ENOMEM)) {
>    103				errln("no memory to readdir of logical block %u of nid %llu",
>    104				      i, EROFS_V(dir)->nid);
>    105				err = -ENOMEM;
>    106				break;
>    107			} else if (IS_ERR(dentry_page)) {
>    108				errln("fail to readdir of logical block %u of nid %llu",
>    109				      i, EROFS_V(dir)->nid);
>  > 110				err = -EFSCORRUPTED;
>    111				break;
>    112			}
>    113	
>    114			de = (struct erofs_dirent *)kmap(dentry_page);
>    115	
>    116			nameoff = le16_to_cpu(de->nameoff);
>    117	
>    118			if (unlikely(nameoff < sizeof(struct erofs_dirent) ||
>    119				     nameoff >= PAGE_SIZE)) {
>    120				errln("%s, invalid de[0].nameoff %u",
>    121				      __func__, nameoff);
>    122	
>    123				err = -EIO;
>    124				goto skip_this;
>    125			}
>    126	
>    127			maxsize = min_t(unsigned int,
>    128					dirsize - ctx->pos + ofs, PAGE_SIZE);
>    129	
>    130			/* search dirents at the arbitrary position */
>    131			if (unlikely(initial)) {
>    132				initial = false;
>    133	
>    134				ofs = roundup(ofs, sizeof(struct erofs_dirent));
>    135				if (unlikely(ofs >= nameoff))
>    136					goto skip_this;
>    137			}
>    138	
>    139			err = erofs_fill_dentries(ctx, de, &ofs, nameoff, maxsize);
>    140	skip_this:
>    141			kunmap(dentry_page);
>    142	
>    143			put_page(dentry_page);
>    144	
>    145			ctx->pos = blknr_to_addr(i) + ofs;
>    146	
>    147			if (unlikely(err))
>    148				break;
>    149			++i;
>    150			ofs = 0;
>    151		}
>    152		return err < 0 ? err : 0;
>    153	}
>    154	
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Gao Xiang Aug. 20, 2019, 6:50 a.m. UTC | #2
Hi Philip,

On Tue, Aug 20, 2019 at 02:50:38PM +0800, Philip Li wrote:
> On Sun, Aug 18, 2019 at 09:25:04PM +0800, Gao Xiang wrote:
> > On Sun, Aug 18, 2019 at 09:17:52PM +0800, kbuild test robot wrote:
> > > Hi Gao,
> > > 
> > > I love your patch! Yet something to improve:
> > > 
> > > [auto build test ERROR on linus/master]
> > > [cannot apply to v5.3-rc4 next-20190816]
> > > [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> > 
> > ... those patches should be applied to staging tree
> > since linux-next has not been updated yet...
> thanks for the feedback, we will consider this to our todo list.

Yes, many confusing reports anyway...
(Just my personal suggestion, maybe we can add some hints on the patch email
to indicate which tree can be applied successfully for ci in the future...)

Thanks,
Gao Xiang

> 
> > 
> > Thanks,
> > Gao Xiang
> > 
> > > 
> > > url:    https://github.com/0day-ci/linux/commits/Gao-Xiang/staging-erofs-fix-an-error-handling-in-erofs_readdir/20190818-191344
> > > config: arm64-allyesconfig (attached as .config)
> > > compiler: aarch64-linux-gcc (GCC) 7.4.0
> > > reproduce:
> > >         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> > >         chmod +x ~/bin/make.cross
> > >         # save the attached .config to linux build tree
> > >         GCC_VERSION=7.4.0 make.cross ARCH=arm64 
> > > 
> > > If you fix the issue, kindly add following tag
> > > Reported-by: kbuild test robot <lkp@intel.com>
> > > 
> > > All errors (new ones prefixed by >>):
> > > 
> > >    drivers/staging/erofs/dir.c: In function 'erofs_readdir':
> > > >> drivers/staging/erofs/dir.c:110:11: error: 'EFSCORRUPTED' undeclared (first use in this function); did you mean 'FS_NRSUPER'?
> > >        err = -EFSCORRUPTED;
> > >               ^~~~~~~~~~~~
> > >               FS_NRSUPER
> > >    drivers/staging/erofs/dir.c:110:11: note: each undeclared identifier is reported only once for each function it appears in
> > > 
> > > vim +110 drivers/staging/erofs/dir.c
> > > 
> > >     85	
> > >     86	static int erofs_readdir(struct file *f, struct dir_context *ctx)
> > >     87	{
> > >     88		struct inode *dir = file_inode(f);
> > >     89		struct address_space *mapping = dir->i_mapping;
> > >     90		const size_t dirsize = i_size_read(dir);
> > >     91		unsigned int i = ctx->pos / EROFS_BLKSIZ;
> > >     92		unsigned int ofs = ctx->pos % EROFS_BLKSIZ;
> > >     93		int err = 0;
> > >     94		bool initial = true;
> > >     95	
> > >     96		while (ctx->pos < dirsize) {
> > >     97			struct page *dentry_page;
> > >     98			struct erofs_dirent *de;
> > >     99			unsigned int nameoff, maxsize;
> > >    100	
> > >    101			dentry_page = read_mapping_page(mapping, i, NULL);
> > >    102			if (dentry_page == ERR_PTR(-ENOMEM)) {
> > >    103				errln("no memory to readdir of logical block %u of nid %llu",
> > >    104				      i, EROFS_V(dir)->nid);
> > >    105				err = -ENOMEM;
> > >    106				break;
> > >    107			} else if (IS_ERR(dentry_page)) {
> > >    108				errln("fail to readdir of logical block %u of nid %llu",
> > >    109				      i, EROFS_V(dir)->nid);
> > >  > 110				err = -EFSCORRUPTED;
> > >    111				break;
> > >    112			}
> > >    113	
> > >    114			de = (struct erofs_dirent *)kmap(dentry_page);
> > >    115	
> > >    116			nameoff = le16_to_cpu(de->nameoff);
> > >    117	
> > >    118			if (unlikely(nameoff < sizeof(struct erofs_dirent) ||
> > >    119				     nameoff >= PAGE_SIZE)) {
> > >    120				errln("%s, invalid de[0].nameoff %u",
> > >    121				      __func__, nameoff);
> > >    122	
> > >    123				err = -EIO;
> > >    124				goto skip_this;
> > >    125			}
> > >    126	
> > >    127			maxsize = min_t(unsigned int,
> > >    128					dirsize - ctx->pos + ofs, PAGE_SIZE);
> > >    129	
> > >    130			/* search dirents at the arbitrary position */
> > >    131			if (unlikely(initial)) {
> > >    132				initial = false;
> > >    133	
> > >    134				ofs = roundup(ofs, sizeof(struct erofs_dirent));
> > >    135				if (unlikely(ofs >= nameoff))
> > >    136					goto skip_this;
> > >    137			}
> > >    138	
> > >    139			err = erofs_fill_dentries(ctx, de, &ofs, nameoff, maxsize);
> > >    140	skip_this:
> > >    141			kunmap(dentry_page);
> > >    142	
> > >    143			put_page(dentry_page);
> > >    144	
> > >    145			ctx->pos = blknr_to_addr(i) + ofs;
> > >    146	
> > >    147			if (unlikely(err))
> > >    148				break;
> > >    149			++i;
> > >    150			ofs = 0;
> > >    151		}
> > >    152		return err < 0 ? err : 0;
> > >    153	}
> > >    154	
> > > 
> > > ---
> > > 0-DAY kernel test infrastructure                Open Source Technology Center
> > > https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
> > 
> >
Philip Li Aug. 20, 2019, 6:50 a.m. UTC | #3
On Sun, Aug 18, 2019 at 09:25:04PM +0800, Gao Xiang wrote:
> On Sun, Aug 18, 2019 at 09:17:52PM +0800, kbuild test robot wrote:
> > Hi Gao,
> > 
> > I love your patch! Yet something to improve:
> > 
> > [auto build test ERROR on linus/master]
> > [cannot apply to v5.3-rc4 next-20190816]
> > [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
> 
> ... those patches should be applied to staging tree
> since linux-next has not been updated yet...
thanks for the feedback, we will consider this to our todo list.

> 
> Thanks,
> Gao Xiang
> 
> > 
> > url:    https://github.com/0day-ci/linux/commits/Gao-Xiang/staging-erofs-fix-an-error-handling-in-erofs_readdir/20190818-191344
> > config: arm64-allyesconfig (attached as .config)
> > compiler: aarch64-linux-gcc (GCC) 7.4.0
> > reproduce:
> >         wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> >         chmod +x ~/bin/make.cross
> >         # save the attached .config to linux build tree
> >         GCC_VERSION=7.4.0 make.cross ARCH=arm64 
> > 
> > If you fix the issue, kindly add following tag
> > Reported-by: kbuild test robot <lkp@intel.com>
> > 
> > All errors (new ones prefixed by >>):
> > 
> >    drivers/staging/erofs/dir.c: In function 'erofs_readdir':
> > >> drivers/staging/erofs/dir.c:110:11: error: 'EFSCORRUPTED' undeclared (first use in this function); did you mean 'FS_NRSUPER'?
> >        err = -EFSCORRUPTED;
> >               ^~~~~~~~~~~~
> >               FS_NRSUPER
> >    drivers/staging/erofs/dir.c:110:11: note: each undeclared identifier is reported only once for each function it appears in
> > 
> > vim +110 drivers/staging/erofs/dir.c
> > 
> >     85	
> >     86	static int erofs_readdir(struct file *f, struct dir_context *ctx)
> >     87	{
> >     88		struct inode *dir = file_inode(f);
> >     89		struct address_space *mapping = dir->i_mapping;
> >     90		const size_t dirsize = i_size_read(dir);
> >     91		unsigned int i = ctx->pos / EROFS_BLKSIZ;
> >     92		unsigned int ofs = ctx->pos % EROFS_BLKSIZ;
> >     93		int err = 0;
> >     94		bool initial = true;
> >     95	
> >     96		while (ctx->pos < dirsize) {
> >     97			struct page *dentry_page;
> >     98			struct erofs_dirent *de;
> >     99			unsigned int nameoff, maxsize;
> >    100	
> >    101			dentry_page = read_mapping_page(mapping, i, NULL);
> >    102			if (dentry_page == ERR_PTR(-ENOMEM)) {
> >    103				errln("no memory to readdir of logical block %u of nid %llu",
> >    104				      i, EROFS_V(dir)->nid);
> >    105				err = -ENOMEM;
> >    106				break;
> >    107			} else if (IS_ERR(dentry_page)) {
> >    108				errln("fail to readdir of logical block %u of nid %llu",
> >    109				      i, EROFS_V(dir)->nid);
> >  > 110				err = -EFSCORRUPTED;
> >    111				break;
> >    112			}
> >    113	
> >    114			de = (struct erofs_dirent *)kmap(dentry_page);
> >    115	
> >    116			nameoff = le16_to_cpu(de->nameoff);
> >    117	
> >    118			if (unlikely(nameoff < sizeof(struct erofs_dirent) ||
> >    119				     nameoff >= PAGE_SIZE)) {
> >    120				errln("%s, invalid de[0].nameoff %u",
> >    121				      __func__, nameoff);
> >    122	
> >    123				err = -EIO;
> >    124				goto skip_this;
> >    125			}
> >    126	
> >    127			maxsize = min_t(unsigned int,
> >    128					dirsize - ctx->pos + ofs, PAGE_SIZE);
> >    129	
> >    130			/* search dirents at the arbitrary position */
> >    131			if (unlikely(initial)) {
> >    132				initial = false;
> >    133	
> >    134				ofs = roundup(ofs, sizeof(struct erofs_dirent));
> >    135				if (unlikely(ofs >= nameoff))
> >    136					goto skip_this;
> >    137			}
> >    138	
> >    139			err = erofs_fill_dentries(ctx, de, &ofs, nameoff, maxsize);
> >    140	skip_this:
> >    141			kunmap(dentry_page);
> >    142	
> >    143			put_page(dentry_page);
> >    144	
> >    145			ctx->pos = blknr_to_addr(i) + ofs;
> >    146	
> >    147			if (unlikely(err))
> >    148				break;
> >    149			++i;
> >    150			ofs = 0;
> >    151		}
> >    152		return err < 0 ? err : 0;
> >    153	}
> >    154	
> > 
> > ---
> > 0-DAY kernel test infrastructure                Open Source Technology Center
> > https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
> 
>
Philip Li Aug. 20, 2019, 6:58 a.m. UTC | #4
> Subject: Re: [PATCH] staging: erofs: fix an error handling in erofs_readdir()
> 
> Hi Philip,
> 
> On Tue, Aug 20, 2019 at 02:50:38PM +0800, Philip Li wrote:
> > On Sun, Aug 18, 2019 at 09:25:04PM +0800, Gao Xiang wrote:
> > > On Sun, Aug 18, 2019 at 09:17:52PM +0800, kbuild test robot wrote:
> > > > Hi Gao,
> > > >
> > > > I love your patch! Yet something to improve:
> > > >
> > > > [auto build test ERROR on linus/master]
> > > > [cannot apply to v5.3-rc4 next-20190816]
> > > > [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system]
> > >
> > > ... those patches should be applied to staging tree
> > > since linux-next has not been updated yet...
> > thanks for the feedback, we will consider this to our todo list.
> 
> Yes, many confusing reports anyway...
> (Just my personal suggestion, maybe we can add some hints on the patch email
> to indicate which tree can be applied successfully for ci in the future...)
thanks, this is good idea. On the other side, we support to add --base option to git format-patch
to automatically suggest the base, refer to https://stackoverflow.com/a/37406982 for detail.
Meanwhile, we will enhance the internal logic to find suitable base if possible.

> 
> Thanks,
> Gao Xiang
> 
> >
> > >
> > > Thanks,
> > > Gao Xiang
> > >
> > > >
> > > > url:    https://github.com/0day-ci/linux/commits/Gao-Xiang/staging-erofs-fix-
> an-error-handling-in-erofs_readdir/20190818-191344
> > > > config: arm64-allyesconfig (attached as .config)
> > > > compiler: aarch64-linux-gcc (GCC) 7.4.0
> > > > reproduce:
> > > >         wget https://raw.githubusercontent.com/intel/lkp-
> tests/master/sbin/make.cross -O ~/bin/make.cross
> > > >         chmod +x ~/bin/make.cross
> > > >         # save the attached .config to linux build tree
> > > >         GCC_VERSION=7.4.0 make.cross ARCH=arm64
> > > >
> > > > If you fix the issue, kindly add following tag
> > > > Reported-by: kbuild test robot <lkp@intel.com>
> > > >
> > > > All errors (new ones prefixed by >>):
> > > >
> > > >    drivers/staging/erofs/dir.c: In function 'erofs_readdir':
> > > > >> drivers/staging/erofs/dir.c:110:11: error: 'EFSCORRUPTED' undeclared
> (first use in this function); did you mean 'FS_NRSUPER'?
> > > >        err = -EFSCORRUPTED;
> > > >               ^~~~~~~~~~~~
> > > >               FS_NRSUPER
> > > >    drivers/staging/erofs/dir.c:110:11: note: each undeclared identifier is
> reported only once for each function it appears in
> > > >
> > > > vim +110 drivers/staging/erofs/dir.c
> > > >
> > > >     85
> > > >     86	static int erofs_readdir(struct file *f, struct dir_context *ctx)
> > > >     87	{
> > > >     88		struct inode *dir = file_inode(f);
> > > >     89		struct address_space *mapping = dir->i_mapping;
> > > >     90		const size_t dirsize = i_size_read(dir);
> > > >     91		unsigned int i = ctx->pos / EROFS_BLKSIZ;
> > > >     92		unsigned int ofs = ctx->pos % EROFS_BLKSIZ;
> > > >     93		int err = 0;
> > > >     94		bool initial = true;
> > > >     95
> > > >     96		while (ctx->pos < dirsize) {
> > > >     97			struct page *dentry_page;
> > > >     98			struct erofs_dirent *de;
> > > >     99			unsigned int nameoff, maxsize;
> > > >    100
> > > >    101			dentry_page = read_mapping_page(mapping, i,
> NULL);
> > > >    102			if (dentry_page == ERR_PTR(-ENOMEM)) {
> > > >    103				errln("no memory to readdir of logical
> block %u of nid %llu",
> > > >    104				      i, EROFS_V(dir)->nid);
> > > >    105				err = -ENOMEM;
> > > >    106				break;
> > > >    107			} else if (IS_ERR(dentry_page)) {
> > > >    108				errln("fail to readdir of logical block %u of
> nid %llu",
> > > >    109				      i, EROFS_V(dir)->nid);
> > > >  > 110				err = -EFSCORRUPTED;
> > > >    111				break;
> > > >    112			}
> > > >    113
> > > >    114			de = (struct erofs_dirent *)kmap(dentry_page);
> > > >    115
> > > >    116			nameoff = le16_to_cpu(de->nameoff);
> > > >    117
> > > >    118			if (unlikely(nameoff < sizeof(struct erofs_dirent) ||
> > > >    119				     nameoff >= PAGE_SIZE)) {
> > > >    120				errln("%s, invalid de[0].nameoff %u",
> > > >    121				      __func__, nameoff);
> > > >    122
> > > >    123				err = -EIO;
> > > >    124				goto skip_this;
> > > >    125			}
> > > >    126
> > > >    127			maxsize = min_t(unsigned int,
> > > >    128					dirsize - ctx->pos + ofs,
> PAGE_SIZE);
> > > >    129
> > > >    130			/* search dirents at the arbitrary position */
> > > >    131			if (unlikely(initial)) {
> > > >    132				initial = false;
> > > >    133
> > > >    134				ofs = roundup(ofs, sizeof(struct
> erofs_dirent));
> > > >    135				if (unlikely(ofs >= nameoff))
> > > >    136					goto skip_this;
> > > >    137			}
> > > >    138
> > > >    139			err = erofs_fill_dentries(ctx, de, &ofs, nameoff,
> maxsize);
> > > >    140	skip_this:
> > > >    141			kunmap(dentry_page);
> > > >    142
> > > >    143			put_page(dentry_page);
> > > >    144
> > > >    145			ctx->pos = blknr_to_addr(i) + ofs;
> > > >    146
> > > >    147			if (unlikely(err))
> > > >    148				break;
> > > >    149			++i;
> > > >    150			ofs = 0;
> > > >    151		}
> > > >    152		return err < 0 ? err : 0;
> > > >    153	}
> > > >    154
> > > >
> > > > ---
> > > > 0-DAY kernel test infrastructure                Open Source Technology Center
> > > > https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
> > >
> > >
Gao Xiang Aug. 20, 2019, 7:16 a.m. UTC | #5
On Tue, Aug 20, 2019 at 06:58:00AM +0000, Li, Philip wrote:
> > Subject: Re: [PATCH] staging: erofs: fix an error handling in erofs_readdir()
> > 
> > Hi Philip,
> > 
> > On Tue, Aug 20, 2019 at 02:50:38PM +0800, Philip Li wrote:
> > > On Sun, Aug 18, 2019 at 09:25:04PM +0800, Gao Xiang wrote:
> > > > On Sun, Aug 18, 2019 at 09:17:52PM +0800, kbuild test robot wrote:
> > > > > Hi Gao,
> > > > >
> > > > > I love your patch! Yet something to improve:
> > > > >
> > > > > [auto build test ERROR on linus/master]
> > > > > [cannot apply to v5.3-rc4 next-20190816]
> > > > > [if your patch is applied to the wrong git tree, please drop us a note to help
> > improve the system]
> > > >
> > > > ... those patches should be applied to staging tree
> > > > since linux-next has not been updated yet...
> > > thanks for the feedback, we will consider this to our todo list.
> > 
> > Yes, many confusing reports anyway...
> > (Just my personal suggestion, maybe we can add some hints on the patch email
> > to indicate which tree can be applied successfully for ci in the future...)
> thanks, this is good idea. On the other side, we support to add --base option to git format-patch
> to automatically suggest the base, refer to https://stackoverflow.com/a/37406982 for detail.

Thanks for your information :) It seems a new patch format,
I will take a try later.

Thanks,
Gao Xiang

> Meanwhile, we will enhance the internal logic to find suitable base if possible.
> 
> > 
> > Thanks,
> > Gao Xiang
> > 
> > >
> > > >
> > > > Thanks,
> > > > Gao Xiang
> > > >
> > > > >
> > > > > url:    https://github.com/0day-ci/linux/commits/Gao-Xiang/staging-erofs-fix-
> > an-error-handling-in-erofs_readdir/20190818-191344
> > > > > config: arm64-allyesconfig (attached as .config)
> > > > > compiler: aarch64-linux-gcc (GCC) 7.4.0
> > > > > reproduce:
> > > > >         wget https://raw.githubusercontent.com/intel/lkp-
> > tests/master/sbin/make.cross -O ~/bin/make.cross
> > > > >         chmod +x ~/bin/make.cross
> > > > >         # save the attached .config to linux build tree
> > > > >         GCC_VERSION=7.4.0 make.cross ARCH=arm64
> > > > >
> > > > > If you fix the issue, kindly add following tag
> > > > > Reported-by: kbuild test robot <lkp@intel.com>
> > > > >
> > > > > All errors (new ones prefixed by >>):
> > > > >
> > > > >    drivers/staging/erofs/dir.c: In function 'erofs_readdir':
> > > > > >> drivers/staging/erofs/dir.c:110:11: error: 'EFSCORRUPTED' undeclared
> > (first use in this function); did you mean 'FS_NRSUPER'?
> > > > >        err = -EFSCORRUPTED;
> > > > >               ^~~~~~~~~~~~
> > > > >               FS_NRSUPER
> > > > >    drivers/staging/erofs/dir.c:110:11: note: each undeclared identifier is
> > reported only once for each function it appears in
> > > > >
> > > > > vim +110 drivers/staging/erofs/dir.c
> > > > >
> > > > >     85
> > > > >     86	static int erofs_readdir(struct file *f, struct dir_context *ctx)
> > > > >     87	{
> > > > >     88		struct inode *dir = file_inode(f);
> > > > >     89		struct address_space *mapping = dir->i_mapping;
> > > > >     90		const size_t dirsize = i_size_read(dir);
> > > > >     91		unsigned int i = ctx->pos / EROFS_BLKSIZ;
> > > > >     92		unsigned int ofs = ctx->pos % EROFS_BLKSIZ;
> > > > >     93		int err = 0;
> > > > >     94		bool initial = true;
> > > > >     95
> > > > >     96		while (ctx->pos < dirsize) {
> > > > >     97			struct page *dentry_page;
> > > > >     98			struct erofs_dirent *de;
> > > > >     99			unsigned int nameoff, maxsize;
> > > > >    100
> > > > >    101			dentry_page = read_mapping_page(mapping, i,
> > NULL);
> > > > >    102			if (dentry_page == ERR_PTR(-ENOMEM)) {
> > > > >    103				errln("no memory to readdir of logical
> > block %u of nid %llu",
> > > > >    104				      i, EROFS_V(dir)->nid);
> > > > >    105				err = -ENOMEM;
> > > > >    106				break;
> > > > >    107			} else if (IS_ERR(dentry_page)) {
> > > > >    108				errln("fail to readdir of logical block %u of
> > nid %llu",
> > > > >    109				      i, EROFS_V(dir)->nid);
> > > > >  > 110				err = -EFSCORRUPTED;
> > > > >    111				break;
> > > > >    112			}
> > > > >    113
> > > > >    114			de = (struct erofs_dirent *)kmap(dentry_page);
> > > > >    115
> > > > >    116			nameoff = le16_to_cpu(de->nameoff);
> > > > >    117
> > > > >    118			if (unlikely(nameoff < sizeof(struct erofs_dirent) ||
> > > > >    119				     nameoff >= PAGE_SIZE)) {
> > > > >    120				errln("%s, invalid de[0].nameoff %u",
> > > > >    121				      __func__, nameoff);
> > > > >    122
> > > > >    123				err = -EIO;
> > > > >    124				goto skip_this;
> > > > >    125			}
> > > > >    126
> > > > >    127			maxsize = min_t(unsigned int,
> > > > >    128					dirsize - ctx->pos + ofs,
> > PAGE_SIZE);
> > > > >    129
> > > > >    130			/* search dirents at the arbitrary position */
> > > > >    131			if (unlikely(initial)) {
> > > > >    132				initial = false;
> > > > >    133
> > > > >    134				ofs = roundup(ofs, sizeof(struct
> > erofs_dirent));
> > > > >    135				if (unlikely(ofs >= nameoff))
> > > > >    136					goto skip_this;
> > > > >    137			}
> > > > >    138
> > > > >    139			err = erofs_fill_dentries(ctx, de, &ofs, nameoff,
> > maxsize);
> > > > >    140	skip_this:
> > > > >    141			kunmap(dentry_page);
> > > > >    142
> > > > >    143			put_page(dentry_page);
> > > > >    144
> > > > >    145			ctx->pos = blknr_to_addr(i) + ofs;
> > > > >    146
> > > > >    147			if (unlikely(err))
> > > > >    148				break;
> > > > >    149			++i;
> > > > >    150			ofs = 0;
> > > > >    151		}
> > > > >    152		return err < 0 ? err : 0;
> > > > >    153	}
> > > > >    154
> > > > >
> > > > > ---
> > > > > 0-DAY kernel test infrastructure                Open Source Technology Center
> > > > > https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
> > > >
> > > >
diff mbox series

Patch

diff --git a/drivers/staging/erofs/dir.c b/drivers/staging/erofs/dir.c
index 5f38382637e6..eb430a031b20 100644
--- a/drivers/staging/erofs/dir.c
+++ b/drivers/staging/erofs/dir.c
@@ -82,8 +82,17 @@  static int erofs_readdir(struct file *f, struct dir_context *ctx)
 		unsigned int nameoff, maxsize;
 
 		dentry_page = read_mapping_page(mapping, i, NULL);
-		if (IS_ERR(dentry_page))
-			continue;
+		if (dentry_page == ERR_PTR(-ENOMEM)) {
+			errln("no memory to readdir of logical block %u of nid %llu",
+			      i, EROFS_V(dir)->nid);
+			err = -ENOMEM;
+			break;
+		} else if (IS_ERR(dentry_page)) {
+			errln("fail to readdir of logical block %u of nid %llu",
+			      i, EROFS_V(dir)->nid);
+			err = -EFSCORRUPTED;
+			break;
+		}
 
 		de = (struct erofs_dirent *)kmap(dentry_page);