f2fs: fix to do sanity check for inline inode

PATCH Superseded Chao Yu 2 participants 3 messages May 15, 2022 – May 17, 2022

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Stable branch F2FS file system

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Chao Yu

author maintainer

2022-05-15 09:06 UTC #0 lore raw

PATCH v3 1/1 f2fs: fix to do sanity check for inline inode

Yanming reported a kernel bug in Bugzilla kernel [1], which can be reproduced. The bug message is:

The kernel message is shown below:

kernel BUG at fs/inode.c:611!

Call Trace:
 evict+0x282/0x4e0
 __dentry_kill+0x2b2/0x4d0
 dput+0x2dd/0x720
 do_renameat2+0x596/0x970
 __x64_sys_rename+0x78/0x90
 do_syscall_64+0x3b/0x90

[1] https://bugzilla.kernel.org/show_bug.cgi?id=215895

The bug is due to fuzzed inode has both inline_data and encrypted flags. During f2fs_evict_inode(), as the inode was deleted by rename(), it will cause inline data conversion due to conflicting flags. The page cache will be polluted and the panic will be triggered in clear_inode().

Try fixing the bug by doing more sanity checks for inline data inode in sanity_check_inode().

Cc [email protected]

Reported-by Ming Yan <[email protected]>

Signed-off-by Chao Yu <[email protected]>

---
v3:
- clean up commit message suggested by Bagas Sanjaya.

 fs/f2fs/f2fs.h  | 8 ++++++++
 fs/f2fs/inode.c | 3 +--
 2 files changed, 9 insertions(+), 2 deletions(-)

fs/f2fs/f2fs.h +8 -0

index 492af5b96de1..0dc2461ef02c 100644
@@ -4126,6 +4126,14 @@ static inline void f2fs_set_encrypted_inode(struct inode *inode)
  */
 static inline bool f2fs_post_read_required(struct inode *inode)
 {
+	/*
+	 * used by sanity_check_inode(), when disk layout fields has not
+	 * been synchronized to inmem fields.
+	 */
+	if (S_ISREG(inode->i_mode) && (file_is_encrypt(inode) ||
+		F2FS_I(inode)->i_flags & F2FS_COMPR_FL ||
+		file_is_verity(inode)))
+		return true;
 	return f2fs_encrypted_file(inode) || fsverity_active(inode) ||
 		f2fs_compressed_file(inode);
 }

fs/f2fs/inode.c +1 -2

index 2fce8fa0dac8..5e494c98e3c2 100644
@@ -276,8 +276,7 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page)
 		}
 	}
 
-	if (f2fs_has_inline_data(inode) &&
-			(!S_ISREG(inode->i_mode) && !S_ISLNK(inode->i_mode))) {
+	if (f2fs_has_inline_data(inode) && !f2fs_may_inline_data(inode)) {
 		set_sbi_flag(sbi, SBI_NEED_FSCK);
 		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);

Signature · 1 line

2.32.0

Jaegeuk Kim

maintainer

2022-05-17 00:46 UTC #1 lore raw

Quoted 40 lines · Chao Yu

Yanming reported a kernel bug in Bugzilla kernel [1], which can be reproduced. The bug message is:
The kernel message is shown below:
kernel BUG at fs/inode.c:611!
Call Trace:
 evict+0x282/0x4e0
 __dentry_kill+0x2b2/0x4d0
 dput+0x2dd/0x720
 do_renameat2+0x596/0x970
 __x64_sys_rename+0x78/0x90
 do_syscall_64+0x3b/0x90
[1] https://bugzilla.kernel.org/show_bug.cgi?id=215895
The bug is due to fuzzed inode has both inline_data and encrypted flags. During f2fs_evict_inode(), as the inode was deleted by rename(), it will cause inline data conversion due to conflicting flags. The page cache will be polluted and the panic will be triggered in clear_inode().
Try fixing the bug by doing more sanity checks for inline data inode in sanity_check_inode().
Cc [email protected]
Reported-by Ming Yan <[email protected]>
Signed-off-by Chao Yu <[email protected]>
---
v3:
- clean up commit message suggested by Bagas Sanjaya.
 fs/f2fs/f2fs.h  | 8 ++++++++
 fs/f2fs/inode.c | 3 +--
 2 files changed, 9 insertions(+), 2 deletions(-)
fs/f2fs/f2fs.h +0 -0
index 492af5b96de1..0dc2461ef02c 100644
@@ -4126,6 +4126,14 @@ static inline void f2fs_set_encrypted_inode(struct inode *inode)
  */

fs/f2fs/f2fs.h static inline void f2fs_set_encrypted_inode(struct inode *inode) · line 4136

Quoted 10 lines

fs/f2fs/f2fs.h +8 -0

 static inline bool f2fs_post_read_required(struct inode *inode)
 {
+	/*
+	 * used by sanity_check_inode(), when disk layout fields has not
+	 * been synchronized to inmem fields.
+	 */
+	if (S_ISREG(inode->i_mode) && (file_is_encrypt(inode) ||
+		F2FS_I(inode)->i_flags & F2FS_COMPR_FL ||
+		file_is_verity(inode)))
+		return true;

Again, I prefer to check this in sanity_check_inode(), since we don't need to check all the time here.

Quoted 19 lines

fs/f2fs/f2fs.h +0 -0

 	return f2fs_encrypted_file(inode) || fsverity_active(inode) ||
 		f2fs_compressed_file(inode);
 }

fs/f2fs/inode.c +1 -2

index 2fce8fa0dac8..5e494c98e3c2 100644
@@ -276,8 +276,7 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page)
 		}
 	}
 
-	if (f2fs_has_inline_data(inode) &&
-			(!S_ISREG(inode->i_mode) && !S_ISLNK(inode->i_mode))) {
+	if (f2fs_has_inline_data(inode) && !f2fs_may_inline_data(inode)) {
 		set_sbi_flag(sbi, SBI_NEED_FSCK);
 		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);

Signature · 1 line

2.32.0

Chao Yu

author maintainer

2022-05-17 02:28 UTC #2 lore raw

Quoted 46 lines · Jaegeuk Kim

Quoted 45 lines · Chao Yu
Yanming reported a kernel bug in Bugzilla kernel [1], which can be reproduced. The bug message is:
The kernel message is shown below:
kernel BUG at fs/inode.c:611!
Call Trace:
  evict+0x282/0x4e0
  __dentry_kill+0x2b2/0x4d0
  dput+0x2dd/0x720
  do_renameat2+0x596/0x970
  __x64_sys_rename+0x78/0x90
  do_syscall_64+0x3b/0x90
[1] https://bugzilla.kernel.org/show_bug.cgi?id=215895
The bug is due to fuzzed inode has both inline_data and encrypted flags. During f2fs_evict_inode(), as the inode was deleted by rename(), it will cause inline data conversion due to conflicting flags. The page cache will be polluted and the panic will be triggered in clear_inode().
Try fixing the bug by doing more sanity checks for inline data inode in sanity_check_inode().
Cc [email protected]
Reported-by Ming Yan <[email protected]>
Signed-off-by Chao Yu <[email protected]>
---
v3:
- clean up commit message suggested by Bagas Sanjaya.
  fs/f2fs/f2fs.h  | 8 ++++++++
  fs/f2fs/inode.c | 3 +--
  2 files changed, 9 insertions(+), 2 deletions(-)
fs/f2fs/f2fs.h +3 -0
index 492af5b96de1..0dc2461ef02c 100644
@@ -4126,6 +4126,14 @@ static inline void f2fs_set_encrypted_inode(struct inode *inode)
   */
  static inline bool f2fs_post_read_required(struct inode *inode)
  {
+	/*
+	 * used by sanity_check_inode(), when disk layout fields has not
+	 * been synchronized to inmem fields.

Quoted 8 lines

fs/f2fs/f2fs.h static inline void f2fs_set_encrypted_inode(struct inode *inode) · line 4136
Quoted 5 lines
fs/f2fs/f2fs.h +5 -0
+	 */
+	if (S_ISREG(inode->i_mode) && (file_is_encrypt(inode) ||
+		F2FS_I(inode)->i_flags & F2FS_COMPR_FL ||
+		file_is_verity(inode)))
+		return true;
Again, I prefer to check this in sanity_check_inode(), since we don't need to check all the time here.

Sure, how about adding a new parameter for f2fs_may_inline_data() to indicate its caller is sanity_check_inode(), and do the checks here only for such path?

Thanks,

Quoted 20 lines

fs/f2fs/f2fs.h +0 -0

  	return f2fs_encrypted_file(inode) || fsverity_active(inode) ||
  		f2fs_compressed_file(inode);
  }

fs/f2fs/inode.c +1 -2

index 2fce8fa0dac8..5e494c98e3c2 100644
@@ -276,8 +276,7 @@ static bool sanity_check_inode(struct inode *inode, struct page *node_page)
  		}
  	}
 
-	if (f2fs_has_inline_data(inode) &&
-			(!S_ISREG(inode->i_mode) && !S_ISLNK(inode->i_mode))) {
+	if (f2fs_has_inline_data(inode) && !f2fs_may_inline_data(inode)) {
  		set_sbi_flag(sbi, SBI_NEED_FSCK);
  		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);

Signature · 1 line

2.32.0