FAILED: patch "[PATCH] nilfs2: reject invalid block index in GC ioctl" failed to apply to 6.6-stable tree

FAILED: patch "[PATCH] nilfs2: reject invalid block index in GC ioctl" failed to apply to 6.6-stable tree

[gregkh]

The patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x a1735eae55448bc79c2da6593455791e886f6ed8
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<stable@vger.kernel.org>' --in-reply-to '2026082453-dynasty-essence-8d05@gregkh' --subject-prefix 'PATCH 6.6.y' 'HEAD^..'

Possible dependencies:



thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From a1735eae55448bc79c2da6593455791e886f6ed8 Mon Sep 17 00:00:00 2001
From: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Date: Fri, 3 Jul 2026 01:07:19 +0900
Subject: [PATCH] nilfs2: reject invalid block index in GC ioctl

Syzbot reported list corruption caused by a double list_add_tail() call on
bh->b_assoc_buffers within nilfs_lookup_dirty_data_buffers().

Analysis revealed that the root cause was the insertion of a page/folio
with a page index of ULONG_MAX into the page cache via the GC ioctl.
filemap_get_folios_tag(), called by nilfs_lookup_dirty_data_buffers(),
repeatedly detects a dirty folio with a page index of ULONG_MAX due to
index wrap-around, leading to duplicate processing of dirty buffers.

As a preparatory step, the GC ioctl loads the page/folio of the block to
be moved during GC and inserts it into the page cache based on information
in the nilfs_vdesc structure passed as an argument.  Normally, this does
not cause issues because the user-space GC library configures the
nilfs_vdesc structure properly.  However, since there is no range check on
the parameters determining the page index, a request with artificially
crafted parameters -- such as those generated by Syzbot -- can result in a
page/folio being inserted with a page index of ULONG_MAX, triggering the
above problem.

This resolves the issue by checking the ranges of 'vd_offset' and
'vd_vblocknr' in the nilfs_vdesc structure that determine the page index,
thereby preventing the invalid page/folio insertions.

Reported-by: syzbot+c37bed40868932d790e9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c37bed40868932d790e9
Fixes: 7942b919f732 ("nilfs2: ioctl operations")
Cc: wuyankun <wuyankun@uniontech.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>

diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index b73f2c5d10f0..0957316e58b8 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -527,6 +527,7 @@ static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
  * Return: 0 on success, or one of the following negative error codes on
  * failure:
  * * %-EEXIST	- Block conflict detected.
+ * * %-EINVAL	- Invalid virtual block descriptor.
  * * %-EIO	- I/O error.
  * * %-ENOENT	- Requested block doesn't exist.
  * * %-ENOMEM	- Insufficient memory available.
@@ -536,15 +537,30 @@ static int nilfs_ioctl_move_inode_block(struct inode *inode,
 					struct list_head *buffers)
 {
 	struct buffer_head *bh;
+	__u64 limit_blkidx = (__u64)inode->i_sb->s_maxbytes >> inode->i_blkbits;
 	int ret;
 
-	if (vdesc->vd_flags == 0)
+	/*
+	 * vblocknr 0 is reserved as an invalid pointer.  Also, limit_blkidx
+	 * ensures that the page index converted from vd_vblocknr never
+	 * overflows the page cache limit and respects the architecture's bmap
+	 * key width.
+	 */
+	if (unlikely(vdesc->vd_vblocknr == 0 ||
+			vdesc->vd_vblocknr >= limit_blkidx))
+		return -EINVAL;
+
+	if (vdesc->vd_flags == 0) {
+		if (unlikely(vdesc->vd_offset >= limit_blkidx))
+			return -EINVAL;
+
 		ret = nilfs_gccache_submit_read_data(
 			inode, vdesc->vd_offset, vdesc->vd_blocknr,
 			vdesc->vd_vblocknr, &bh);
-	else
+	} else {
 		ret = nilfs_gccache_submit_read_node(
 			inode, vdesc->vd_blocknr, vdesc->vd_vblocknr, &bh);
+	}
 
 	if (unlikely(ret < 0)) {
 		if (ret == -ENOENT)

[PATCH 6.6.y 1/2] nilfs2: correct return value kernel-doc descriptions for ioctl functions

[Sasha Levin]

From: Ryusuke Konishi <konishi.ryusuke@gmail.com>

[ Upstream commit 17c46a45cdb94c500f4e93b176cdd61931b03020 ]

Patch series "nilfs2: fix kernel-doc comments for function return values",
v2.

This series fixes the inadequacies in the return value descriptions in
nilfs2's kernel-doc comments (mainly incorrect formatting), as well as the
lack of return value descriptions themselves, and fixes most of the
remaining warnings that are output when the kernel-doc script is run with
the "-Wall" option.

This patch (of 7):

In the kernel-doc comments for functions, there are many cases where the
format of the return value description is inaccurate, such as "Return
Value: ...", which causes many warnings to be output when the kernel-doc
script is executed with the "-Wall" option.

This fixes such incorrectly formatted return value descriptions for ioctl
functions.

Link: https://lkml.kernel.org/r/20250110010530.21872-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20250110010530.21872-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: "Brian G ." <gissf1@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Stable-dep-of: a1735eae5544 ("nilfs2: reject invalid block index in GC ioctl")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nilfs2/ioctl.c | 241 +++++++++++++++++++---------------------------
 1 file changed, 100 insertions(+), 141 deletions(-)

diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 1a6868afa9143..327ba5922429c 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -32,17 +32,14 @@
  * @dofunc: concrete function of get/set metadata info
  *
  * Description: nilfs_ioctl_wrap_copy() gets/sets metadata info by means of
- * calling dofunc() function on the basis of @argv argument.
- *
- * Return Value: On success, 0 is returned and requested metadata info
- * is copied into userspace. On error, one of the following
- * negative error codes is returned.
- *
- * %-EINVAL - Invalid arguments from userspace.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EFAULT - Failure during execution of requested operation.
+ * calling dofunc() function on the basis of @argv argument.  If successful,
+ * the requested metadata information is copied to userspace memory.
+ *
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EFAULT	- Failure during execution of requested operation.
+ * * %-EINVAL	- Invalid arguments from userspace.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs,
 				 struct nilfs_argv *argv, int dir,
@@ -176,13 +173,10 @@ static int nilfs_ioctl_getversion(struct inode *inode, void __user *argp)
  * given checkpoint between checkpoint and snapshot state. This ioctl
  * is used in chcp and mkcp utilities.
  *
- * Return Value: On success, 0 is returned and mode of a checkpoint is
- * changed. On error, one of the following negative error codes
- * is returned.
- *
- * %-EPERM - Operation not permitted.
- *
- * %-EFAULT - Failure during checkpoint mode changing.
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * %-EFAULT	- Failure during checkpoint mode changing.
+ * %-EPERM	- Operation not permitted.
  */
 static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
 				     unsigned int cmd, void __user *argp)
@@ -230,13 +224,10 @@ static int nilfs_ioctl_change_cpmode(struct inode *inode, struct file *filp,
  * checkpoint from NILFS2 file system. This ioctl is used in rmcp
  * utility.
  *
- * Return Value: On success, 0 is returned and a checkpoint is
- * removed. On error, one of the following negative error codes
- * is returned.
- *
- * %-EPERM - Operation not permitted.
- *
- * %-EFAULT - Failure during checkpoint removing.
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * %-EFAULT	- Failure during checkpoint removing.
+ * %-EPERM	- Operation not permitted.
  */
 static int
 nilfs_ioctl_delete_checkpoint(struct inode *inode, struct file *filp,
@@ -282,7 +273,7 @@ nilfs_ioctl_delete_checkpoint(struct inode *inode, struct file *filp,
  * requested checkpoints. The NILFS_IOCTL_GET_CPINFO ioctl is used in
  * lscp utility and by nilfs_cleanerd daemon.
  *
- * Return value: count of nilfs_cpinfo structures in output buffer.
+ * Return: Count of nilfs_cpinfo structures in output buffer.
  */
 static ssize_t
 nilfs_ioctl_do_get_cpinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
@@ -306,17 +297,14 @@ nilfs_ioctl_do_get_cpinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
  *
  * Description: nilfs_ioctl_get_cpstat() returns information about checkpoints.
  * The NILFS_IOCTL_GET_CPSTAT ioctl is used by lscp, rmcp utilities
- * and by nilfs_cleanerd daemon.
- *
- * Return Value: On success, 0 is returned, and checkpoints information is
- * copied into userspace pointer @argp. On error, one of the following
- * negative error codes is returned.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EFAULT - Failure during getting checkpoints statistics.
+ * and by nilfs_cleanerd daemon.  The checkpoint statistics are copied to
+ * the userspace memory pointed to by @argp.
+ *
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EFAULT	- Failure during getting checkpoints statistics.
+ * * %-EIO	- I/O error.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_get_cpstat(struct inode *inode, struct file *filp,
 				  unsigned int cmd, void __user *argp)
@@ -349,7 +337,8 @@ static int nilfs_ioctl_get_cpstat(struct inode *inode, struct file *filp,
  * info about requested segments. The NILFS_IOCTL_GET_SUINFO ioctl is used
  * in lssu, nilfs_resize utilities and by nilfs_cleanerd daemon.
  *
- * Return value: count of nilfs_suinfo structures in output buffer.
+ * Return: Count of nilfs_suinfo structures in output buffer on success,
+ * or a negative error code on failure.
  */
 static ssize_t
 nilfs_ioctl_do_get_suinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
@@ -373,17 +362,14 @@ nilfs_ioctl_do_get_suinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
  *
  * Description: nilfs_ioctl_get_sustat() returns segment usage statistics.
  * The NILFS_IOCTL_GET_SUSTAT ioctl is used in lssu, nilfs_resize utilities
- * and by nilfs_cleanerd daemon.
- *
- * Return Value: On success, 0 is returned, and segment usage information is
- * copied into userspace pointer @argp. On error, one of the following
- * negative error codes is returned.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EFAULT - Failure during getting segment usage statistics.
+ * and by nilfs_cleanerd daemon.  The requested segment usage information is
+ * copied to the userspace memory pointed to by @argp.
+ *
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EFAULT	- Failure during getting segment usage statistics.
+ * * %-EIO	- I/O error.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_get_sustat(struct inode *inode, struct file *filp,
 				  unsigned int cmd, void __user *argp)
@@ -416,7 +402,8 @@ static int nilfs_ioctl_get_sustat(struct inode *inode, struct file *filp,
  * on virtual block addresses. The NILFS_IOCTL_GET_VINFO ioctl is used
  * by nilfs_cleanerd daemon.
  *
- * Return value: count of nilfs_vinfo structures in output buffer.
+ * Return: Count of nilfs_vinfo structures in output buffer on success, or
+ * a negative error code on failure.
  */
 static ssize_t
 nilfs_ioctl_do_get_vinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
@@ -443,7 +430,8 @@ nilfs_ioctl_do_get_vinfo(struct the_nilfs *nilfs, __u64 *posp, int flags,
  * about descriptors of disk block numbers. The NILFS_IOCTL_GET_BDESCS ioctl
  * is used by nilfs_cleanerd daemon.
  *
- * Return value: count of nilfs_bdescs structures in output buffer.
+ * Return: Count of nilfs_bdescs structures in output buffer on success, or
+ * a negative error code on failure.
  */
 static ssize_t
 nilfs_ioctl_do_get_bdescs(struct the_nilfs *nilfs, __u64 *posp, int flags,
@@ -480,19 +468,15 @@ nilfs_ioctl_do_get_bdescs(struct the_nilfs *nilfs, __u64 *posp, int flags,
  *
  * Description: nilfs_ioctl_do_get_bdescs() function returns information
  * about descriptors of disk block numbers. The NILFS_IOCTL_GET_BDESCS ioctl
- * is used by nilfs_cleanerd daemon.
- *
- * Return Value: On success, 0 is returned, and disk block descriptors are
- * copied into userspace pointer @argp. On error, one of the following
- * negative error codes is returned.
- *
- * %-EINVAL - Invalid arguments from userspace.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EFAULT - Failure during getting disk block descriptors.
+ * is used by nilfs_cleanerd daemon.  If successful, disk block descriptors
+ * are copied to userspace pointer @argp.
+ *
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EFAULT	- Failure during getting disk block descriptors.
+ * * %-EINVAL	- Invalid arguments from userspace.
+ * * %-EIO	- I/O error.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
 				  unsigned int cmd, void __user *argp)
@@ -526,16 +510,12 @@ static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
  * Description: nilfs_ioctl_move_inode_block() function registers data/node
  * buffer in the GC pagecache and submit read request.
  *
- * Return Value: On success, 0 is returned. On error, one of the following
- * negative error codes is returned.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-ENOENT - Requested block doesn't exist.
- *
- * %-EEXIST - Blocks conflict is detected.
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EEXIST	- Block conflict detected.
+ * * %-EIO	- I/O error.
+ * * %-ENOENT	- Requested block doesn't exist.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_move_inode_block(struct inode *inode,
 					struct nilfs_vdesc *vdesc,
@@ -590,8 +570,8 @@ static int nilfs_ioctl_move_inode_block(struct inode *inode,
  * blocks that garbage collector specified with the array of nilfs_vdesc
  * structures and stores them into page caches of GC inodes.
  *
- * Return Value: Number of processed nilfs_vdesc structures or
- * error code, otherwise.
+ * Return: Number of processed nilfs_vdesc structures on success, or
+ * a negative error code on failure.
  */
 static int nilfs_ioctl_move_blocks(struct super_block *sb,
 				   struct nilfs_argv *argv, void *buf)
@@ -668,14 +648,11 @@ static int nilfs_ioctl_move_blocks(struct super_block *sb,
  * in the period from p_start to p_end, excluding p_end itself. The checkpoints
  * which have been already deleted are ignored.
  *
- * Return Value: Number of processed nilfs_period structures or
- * error code, otherwise.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EINVAL - invalid checkpoints.
+ * Return: Number of processed nilfs_period structures on success, or one of
+ * the following negative error codes on failure:
+ * * %-EINVAL	- invalid checkpoints.
+ * * %-EIO	- I/O error.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
 					  struct nilfs_argv *argv, void *buf)
@@ -703,14 +680,11 @@ static int nilfs_ioctl_delete_checkpoints(struct the_nilfs *nilfs,
  * Description: nilfs_ioctl_free_vblocknrs() function frees
  * the virtual block numbers specified by @buf and @argv->v_nmembs.
  *
- * Return Value: Number of processed virtual block numbers or
- * error code, otherwise.
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-ENOENT - The virtual block number have not been allocated.
+ * Return: Number of processed virtual block numbers on success, or one of the
+ * following negative error codes on failure:
+ * * %-EIO	- I/O error.
+ * * %-ENOENT	- Unallocated virtual block number.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
 				      struct nilfs_argv *argv, void *buf)
@@ -732,14 +706,11 @@ static int nilfs_ioctl_free_vblocknrs(struct the_nilfs *nilfs,
  * Description: nilfs_ioctl_mark_blocks_dirty() function marks
  * metadata file or data blocks as dirty.
  *
- * Return Value: Number of processed block descriptors or
- * error code, otherwise.
- *
- * %-ENOMEM - Insufficient memory available.
- *
- * %-EIO - I/O error
- *
- * %-ENOENT - the specified block does not exist (hole block)
+ * Return: Number of processed block descriptors on success, or one of the
+ * following negative error codes on failure:
+ * * %-EIO	- I/O error.
+ * * %-ENOENT	- Non-existent block (hole block).
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_mark_blocks_dirty(struct the_nilfs *nilfs,
 					 struct nilfs_argv *argv, void *buf)
@@ -844,7 +815,7 @@ int nilfs_ioctl_prepare_clean_segments(struct the_nilfs *nilfs,
  * from userspace. The NILFS_IOCTL_CLEAN_SEGMENTS ioctl is used by
  * nilfs_cleanerd daemon.
  *
- * Return Value: On success, 0 is returned or error code, otherwise.
+ * Return: 0 on success, or a negative error code on failure.
  */
 static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp,
 				      unsigned int cmd, void __user *argp)
@@ -970,20 +941,14 @@ static int nilfs_ioctl_clean_segments(struct inode *inode, struct file *filp,
  * and metadata are written out to the device when it successfully
  * returned.
  *
- * Return Value: On success, 0 is retured. On errors, one of the following
- * negative error code is returned.
- *
- * %-EROFS - Read only filesystem.
- *
- * %-EIO - I/O error
- *
- * %-ENOSPC - No space left on device (only in a panic state).
- *
- * %-ERESTARTSYS - Interrupted.
- *
- * %-ENOMEM - Insufficient memory available.
- *
- * %-EFAULT - Failure during execution of requested operation.
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EFAULT		- Failure during execution of requested operation.
+ * * %-EIO		- I/O error.
+ * * %-ENOMEM		- Insufficient memory available.
+ * * %-ENOSPC		- No space left on device (only in a panic state).
+ * * %-ERESTARTSYS	- Interrupted.
+ * * %-EROFS		- Read only filesystem.
  */
 static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
 			    unsigned int cmd, void __user *argp)
@@ -1017,7 +982,7 @@ static int nilfs_ioctl_sync(struct inode *inode, struct file *filp,
  * @filp: file object
  * @argp: pointer on argument from userspace
  *
- * Return Value: On success, 0 is returned or error code, otherwise.
+ * Return: 0 on success, or a negative error code on failure.
  */
 static int nilfs_ioctl_resize(struct inode *inode, struct file *filp,
 			      void __user *argp)
@@ -1053,7 +1018,7 @@ static int nilfs_ioctl_resize(struct inode *inode, struct file *filp,
  * checks the arguments from userspace and calls nilfs_sufile_trim_fs, which
  * performs the actual trim operation.
  *
- * Return Value: On success, 0 is returned or negative error code, otherwise.
+ * Return: 0 on success, or a negative error code on failure.
  */
 static int nilfs_ioctl_trim_fs(struct inode *inode, void __user *argp)
 {
@@ -1095,7 +1060,7 @@ static int nilfs_ioctl_trim_fs(struct inode *inode, void __user *argp)
  * of segments in bytes and upper limit of segments in bytes.
  * The NILFS_IOCTL_SET_ALLOC_RANGE is used by nilfs_resize utility.
  *
- * Return Value: On success, 0 is returned or error code, otherwise.
+ * Return: 0 on success, or a negative error code on failure.
  */
 static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp)
 {
@@ -1146,17 +1111,15 @@ static int nilfs_ioctl_set_alloc_range(struct inode *inode, void __user *argp)
  * @dofunc: concrete function of getting metadata info
  *
  * Description: nilfs_ioctl_get_info() gets metadata info by means of
- * calling dofunc() function.
- *
- * Return Value: On success, 0 is returned and requested metadata info
- * is copied into userspace. On error, one of the following
- * negative error codes is returned.
- *
- * %-EINVAL - Invalid arguments from userspace.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EFAULT - Failure during execution of requested operation.
+ * calling dofunc() function.  The requested metadata information is copied
+ * to userspace memory @argp.
+ *
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EFAULT	- Failure during execution of requested operation.
+ * * %-EINVAL	- Invalid arguments from userspace.
+ * * %-EIO	- I/O error.
+ * * %-ENOMEM	- Insufficient memory available.
  */
 static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp,
 				unsigned int cmd, void __user *argp,
@@ -1196,18 +1159,14 @@ static int nilfs_ioctl_get_info(struct inode *inode, struct file *filp,
  * encapsulated in nilfs_argv and updates the segment usage info
  * according to the flags in nilfs_suinfo_update.
  *
- * Return Value: On success, 0 is returned. On error, one of the
- * following negative error codes is returned.
- *
- * %-EPERM - Not enough permissions
- *
- * %-EFAULT - Error copying input data
- *
- * %-EIO - I/O error.
- *
- * %-ENOMEM - Insufficient amount of memory available.
- *
- * %-EINVAL - Invalid values in input (segment number, flags or nblocks)
+ * Return: 0 on success, or one of the following negative error codes on
+ * failure:
+ * * %-EEXIST	- Block conflict detected.
+ * * %-EFAULT	- Error copying input data.
+ * * %-EINVAL	- Invalid values in input (segment number, flags or nblocks).
+ * * %-EIO	- I/O error.
+ * * %-ENOMEM	- Insufficient memory available.
+ * * %-EPERM	- Not enough permissions.
  */
 static int nilfs_ioctl_set_suinfo(struct inode *inode, struct file *filp,
 				unsigned int cmd, void __user *argp)
-- 
2.53.0

[PATCH 6.6.y 2/2] nilfs2: reject invalid block index in GC ioctl

[Sasha Levin]

From: Ryusuke Konishi <konishi.ryusuke@gmail.com>

[ Upstream commit a1735eae55448bc79c2da6593455791e886f6ed8 ]

Syzbot reported list corruption caused by a double list_add_tail() call on
bh->b_assoc_buffers within nilfs_lookup_dirty_data_buffers().

Analysis revealed that the root cause was the insertion of a page/folio
with a page index of ULONG_MAX into the page cache via the GC ioctl.
filemap_get_folios_tag(), called by nilfs_lookup_dirty_data_buffers(),
repeatedly detects a dirty folio with a page index of ULONG_MAX due to
index wrap-around, leading to duplicate processing of dirty buffers.

As a preparatory step, the GC ioctl loads the page/folio of the block to
be moved during GC and inserts it into the page cache based on information
in the nilfs_vdesc structure passed as an argument.  Normally, this does
not cause issues because the user-space GC library configures the
nilfs_vdesc structure properly.  However, since there is no range check on
the parameters determining the page index, a request with artificially
crafted parameters -- such as those generated by Syzbot -- can result in a
page/folio being inserted with a page index of ULONG_MAX, triggering the
above problem.

This resolves the issue by checking the ranges of 'vd_offset' and
'vd_vblocknr' in the nilfs_vdesc structure that determine the page index,
thereby preventing the invalid page/folio insertions.

Reported-by: syzbot+c37bed40868932d790e9@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=c37bed40868932d790e9
Fixes: 7942b919f732 ("nilfs2: ioctl operations")
Cc: wuyankun <wuyankun@uniontech.com>
Cc: stable@vger.kernel.org
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Viacheslav Dubeyko <slava@dubeyko.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 fs/nilfs2/ioctl.c | 20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index 327ba5922429c..f8c53a411d549 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -513,6 +513,7 @@ static int nilfs_ioctl_get_bdescs(struct inode *inode, struct file *filp,
  * Return: 0 on success, or one of the following negative error codes on
  * failure:
  * * %-EEXIST	- Block conflict detected.
+ * * %-EINVAL	- Invalid virtual block descriptor.
  * * %-EIO	- I/O error.
  * * %-ENOENT	- Requested block doesn't exist.
  * * %-ENOMEM	- Insufficient memory available.
@@ -522,15 +523,30 @@ static int nilfs_ioctl_move_inode_block(struct inode *inode,
 					struct list_head *buffers)
 {
 	struct buffer_head *bh;
+	__u64 limit_blkidx = (__u64)inode->i_sb->s_maxbytes >> inode->i_blkbits;
 	int ret;
 
-	if (vdesc->vd_flags == 0)
+	/*
+	 * vblocknr 0 is reserved as an invalid pointer.  Also, limit_blkidx
+	 * ensures that the page index converted from vd_vblocknr never
+	 * overflows the page cache limit and respects the architecture's bmap
+	 * key width.
+	 */
+	if (unlikely(vdesc->vd_vblocknr == 0 ||
+			vdesc->vd_vblocknr >= limit_blkidx))
+		return -EINVAL;
+
+	if (vdesc->vd_flags == 0) {
+		if (unlikely(vdesc->vd_offset >= limit_blkidx))
+			return -EINVAL;
+
 		ret = nilfs_gccache_submit_read_data(
 			inode, vdesc->vd_offset, vdesc->vd_blocknr,
 			vdesc->vd_vblocknr, &bh);
-	else
+	} else {
 		ret = nilfs_gccache_submit_read_node(
 			inode, vdesc->vd_blocknr, vdesc->vd_vblocknr, &bh);
+	}
 
 	if (unlikely(ret < 0)) {
 		if (ret == -ENOENT)
-- 
2.53.0