[PATCH] jfs: validate max amount of blocks before allocation.

[PATCH] jfs: validate max amount of blocks before allocation.

[Aleksei Filippov]

From: Alexei Filippov <halip0503@gmail.com>

The lack of checking bmp->db_max_freebud in extBalloc() can lead to
shift out of bounds, so this patch prevents undefined behavior,
because bmp->db_max_freebud == -1 only if there
is no free space.

Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
---
 fs/jfs/jfs_extent.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
index ae99a7e232ee..a82751e6c47f 100644
--- a/fs/jfs/jfs_extent.c
+++ b/fs/jfs/jfs_extent.c
@@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
 	 * blocks in the map. in that case, we'll start off with the
 	 * maximum free.
 	 */
+
+	/* give up if no space left */
+	if (bmp->db_maxfreebud == -1)
+		return -ENOSPC;
+
 	max = (s64) 1 << bmp->db_maxfreebud;
 	if (*nblocks >= max && *nblocks > nbperpage)
 		nb = nblks = (max > nbperpage) ? max : nbperpage;
-- 
2.25.1

Re: [PATCH] jfs: validate max amount of blocks before allocation.

[Greg KH]

On Sat, Jul 22, 2023 at 05:24:01PM +0300, Aleksei Filippov wrote:
> From: Alexei Filippov <halip0503@gmail.com>
> 
> The lack of checking bmp->db_max_freebud in extBalloc() can lead to
> shift out of bounds, so this patch prevents undefined behavior,
> because bmp->db_max_freebud == -1 only if there
> is no free space.

Please wrap at 72 columns properly.


> 
> Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
> Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
> ---
>  fs/jfs/jfs_extent.c | 5 +++++
>  1 file changed, 5 insertions(+)

What commit id does this fix?

Is it needed for stable kernels?  If so, please tag it as such.

thanks,

greg k-h

[PATCH] jfs: validate max amount of blocks before allocation.

[Aleksei Filippov]

From: Alexei Filippov <halip0503@gmail.com>

The lack of checking bmp->db_max_freebud in extBalloc() can lead to
shift out of bounds, so this patch prevents undefined behavior, because
bmp->db_max_freebud == -1 only if there is no free space.

Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
---
 fs/jfs/jfs_extent.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
index ae99a7e232ee..a82751e6c47f 100644
--- a/fs/jfs/jfs_extent.c
+++ b/fs/jfs/jfs_extent.c
@@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
 	 * blocks in the map. in that case, we'll start off with the
 	 * maximum free.
 	 */
+
+	/* give up if no space left */
+	if (bmp->db_maxfreebud == -1)
+		return -ENOSPC;
+
 	max = (s64) 1 << bmp->db_maxfreebud;
 	if (*nblocks >= max && *nblocks > nbperpage)
 		nb = nblks = (max > nbperpage) ? max : nbperpage;
-- 
2.25.1

Re: [PATCH] jfs: validate max amount of blocks before allocation.

[Greg KH]

On Sun, Jul 23, 2023 at 03:02:09PM +0300, Aleksei Filippov wrote:
> From: Alexei Filippov <halip0503@gmail.com>
> 
> The lack of checking bmp->db_max_freebud in extBalloc() can lead to
> shift out of bounds, so this patch prevents undefined behavior, because
> bmp->db_max_freebud == -1 only if there is no free space.
> 
> Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
> ---
>  fs/jfs/jfs_extent.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
> index ae99a7e232ee..a82751e6c47f 100644
> --- a/fs/jfs/jfs_extent.c
> +++ b/fs/jfs/jfs_extent.c
> @@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
>  	 * blocks in the map. in that case, we'll start off with the
>  	 * maximum free.
>  	 */
> +
> +	/* give up if no space left */
> +	if (bmp->db_maxfreebud == -1)
> +		return -ENOSPC;
> +
>  	max = (s64) 1 << bmp->db_maxfreebud;
>  	if (*nblocks >= max && *nblocks > nbperpage)
>  		nb = nblks = (max > nbperpage) ? max : nbperpage;
> -- 
> 2.25.1
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
kernel tree.

You are receiving this message because of the following common error(s)
as indicated below:

- This looks like a new version of a previously submitted patch, but you
  did not list below the --- line any changes from the previous version.
  Please read the section entitled "The canonical patch format" in the
  kernel file, Documentation/process/submitting-patches.rst for what
  needs to be done here to properly describe this.

If you wish to discuss this problem further, or you have questions about
how to resolve this issue, please feel free to respond to this email and
Greg will reply once he has dug out from the pending patches received
from other developers.

thanks,

greg k-h's patch email bot

[PATCH v3] jfs: validate max amount of blocks before allocation.

[Aleksei Filippov]

From: Alexei Filippov <halip0503@gmail.com>

The lack of checking bmp->db_max_freebud in extBalloc() can lead to
shift out of bounds, so this patch prevents undefined behavior, because
bmp->db_max_freebud == -1 only if there is no free space.

Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
---
 fs/jfs/jfs_extent.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
index ae99a7e232ee..a82751e6c47f 100644
--- a/fs/jfs/jfs_extent.c
+++ b/fs/jfs/jfs_extent.c
@@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
 	 * blocks in the map. in that case, we'll start off with the
 	 * maximum free.
 	 */
+
+	/* give up if no space left */
+	if (bmp->db_maxfreebud == -1)
+		return -ENOSPC;
+
 	max = (s64) 1 << bmp->db_maxfreebud;
 	if (*nblocks >= max && *nblocks > nbperpage)
 		nb = nblks = (max > nbperpage) ? max : nbperpage;
-- 
2.25.1

Fix commit message.

Re: [PATCH v3] jfs: validate max amount of blocks before allocation.

[Greg KH]

On Sun, Jul 23, 2023 at 04:29:59PM +0300, Aleksei Filippov wrote:
> From: Alexei Filippov <halip0503@gmail.com>
> 
> The lack of checking bmp->db_max_freebud in extBalloc() can lead to
> shift out of bounds, so this patch prevents undefined behavior, because
> bmp->db_max_freebud == -1 only if there is no free space.
> 
> Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
> ---
>  fs/jfs/jfs_extent.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
> index ae99a7e232ee..a82751e6c47f 100644
> --- a/fs/jfs/jfs_extent.c
> +++ b/fs/jfs/jfs_extent.c
> @@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
>  	 * blocks in the map. in that case, we'll start off with the
>  	 * maximum free.
>  	 */
> +
> +	/* give up if no space left */
> +	if (bmp->db_maxfreebud == -1)
> +		return -ENOSPC;
> +
>  	max = (s64) 1 << bmp->db_maxfreebud;
>  	if (*nblocks >= max && *nblocks > nbperpage)
>  		nb = nblks = (max > nbperpage) ? max : nbperpage;
> -- 
> 2.25.1
> 
> Fix commit message.

The --- information for the version goes below the first --- line, not
the last.  Look at the examples on the mailing lists for the proper
format.

thanks,

greg k-h

[PATCH v4] jfs: validate max amount of blocks before allocation.

[Aleksei Filippov]

From: Alexei Filippov <halip0503@gmail.com>

The lack of checking bmp->db_max_freebud in extBalloc() can lead to
shift out of bounds, so this patch prevents undefined behavior, because
bmp->db_max_freebud == -1 only if there is no free space.

Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
---
Changes:
Fix commit message.
 fs/jfs/jfs_extent.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
index ae99a7e232ee..a82751e6c47f 100644
--- a/fs/jfs/jfs_extent.c
+++ b/fs/jfs/jfs_extent.c
@@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
 	 * blocks in the map. in that case, we'll start off with the
 	 * maximum free.
 	 */
+
+	/* give up if no space left */
+	if (bmp->db_maxfreebud == -1)
+		return -ENOSPC;
+
 	max = (s64) 1 << bmp->db_maxfreebud;
 	if (*nblocks >= max && *nblocks > nbperpage)
 		nb = nblks = (max > nbperpage) ? max : nbperpage;
-- 
2.25.1

Re: [PATCH v4] jfs: validate max amount of blocks before allocation.

[Greg KH]

On Sun, Jul 23, 2023 at 04:58:22PM +0300, Aleksei Filippov wrote:
> From: Alexei Filippov <halip0503@gmail.com>
> 
> The lack of checking bmp->db_max_freebud in extBalloc() can lead to
> shift out of bounds, so this patch prevents undefined behavior, because
> bmp->db_max_freebud == -1 only if there is no free space.
> 
> Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
> ---
> Changes:
> Fix commit message.
>  fs/jfs/jfs_extent.c | 5 +++++
>  1 file changed, 5 insertions(+)

{sigh}

Please, take some time, read the documentation for how to do this
correctly.  Wait a day, and then submit it again, properly.

Also, do you have a jfs system?  Isn't this filesystem obsolete?

thanks,

greg k-h

[PATCH v5] jfs: validate max amount of blocks before allocation.

[Aleksei Filippov]

From: Alexei Filippov <halip0503@gmail.com>

The lack of checking bmp->db_max_freebud in extBalloc() can lead to
shift out of bounds, so this patch prevents undefined behavior, because
bmp->db_max_freebud == -1 only if there is no free space.

Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
---

Changes since v1:
	-Commit message fix. Add Fixes line.
Changes since v2-v4:
	-Commit message fixes.
 fs/jfs/jfs_extent.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
index ae99a7e232ee..a82751e6c47f 100644
--- a/fs/jfs/jfs_extent.c
+++ b/fs/jfs/jfs_extent.c
@@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
 	 * blocks in the map. in that case, we'll start off with the
 	 * maximum free.
 	 */
+
+	/* give up if no space left */
+	if (bmp->db_maxfreebud == -1)
+		return -ENOSPC;
+
 	max = (s64) 1 << bmp->db_maxfreebud;
 	if (*nblocks >= max && *nblocks > nbperpage)
 		nb = nblks = (max > nbperpage) ? max : nbperpage;
-- 
2.25.1

Re: [PATCH v5] jfs: validate max amount of blocks before allocation.

[Dave Kleikamp]

On 8/19/23 12:32PM, Aleksei Filippov wrote:
> From: Alexei Filippov <halip0503@gmail.com>
> 
> The lack of checking bmp->db_max_freebud in extBalloc() can lead to
> shift out of bounds, so this patch prevents undefined behavior, because
> bmp->db_max_freebud == -1 only if there is no free space.

Thanks. Applied.

> 
> Signed-off-by: Aleksei Filippov <halip0503@gmail.com>
> Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
> Reported-and-tested-by: syzbot+5f088f29593e6b4c8db8@syzkaller.appspotmail.com
> Closes: https://syzkaller.appspot.com/bug?id=01abadbd6ae6a08b1f1987aa61554c6b3ac19ff2
> ---
> 
> Changes since v1:
> 	-Commit message fix. Add Fixes line.
> Changes since v2-v4:
> 	-Commit message fixes.
>   fs/jfs/jfs_extent.c | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/fs/jfs/jfs_extent.c b/fs/jfs/jfs_extent.c
> index ae99a7e232ee..a82751e6c47f 100644
> --- a/fs/jfs/jfs_extent.c
> +++ b/fs/jfs/jfs_extent.c
> @@ -311,6 +311,11 @@ extBalloc(struct inode *ip, s64 hint, s64 * nblocks, s64 * blkno)
>   	 * blocks in the map. in that case, we'll start off with the
>   	 * maximum free.
>   	 */
> +
> +	/* give up if no space left */
> +	if (bmp->db_maxfreebud == -1)
> +		return -ENOSPC;
> +
>   	max = (s64) 1 << bmp->db_maxfreebud;
>   	if (*nblocks >= max && *nblocks > nbperpage)
>   		nb = nblks = (max > nbperpage) ? max : nbperpage;