2022-05-16 09:21:47

by Chao Yu

[permalink] [raw]
Subject: [PATCH v3] 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(-)

diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
index 492af5b96de1..0dc2461ef02c 100644
--- a/fs/f2fs/f2fs.h
+++ b/fs/f2fs/f2fs.h
@@ -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);
}
diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
index 2fce8fa0dac8..5e494c98e3c2 100644
--- a/fs/f2fs/inode.c
+++ b/fs/f2fs/inode.c
@@ -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);
--
2.32.0



2022-05-17 03:58:20

by Chao Yu

[permalink] [raw]
Subject: Re: [PATCH v3] f2fs: fix to do sanity check for inline inode

On 2022/5/17 8:46, Jaegeuk Kim wrote:
> On 05/15, Chao Yu wrote:
>> 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(-)
>>
>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>> index 492af5b96de1..0dc2461ef02c 100644
>> --- a/fs/f2fs/f2fs.h
>> +++ b/fs/f2fs/f2fs.h
>> @@ -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;
>
> 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,

>
>> return f2fs_encrypted_file(inode) || fsverity_active(inode) ||
>> f2fs_compressed_file(inode);
>> }
>> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
>> index 2fce8fa0dac8..5e494c98e3c2 100644
>> --- a/fs/f2fs/inode.c
>> +++ b/fs/f2fs/inode.c
>> @@ -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);
>> --
>> 2.32.0

2022-05-17 08:42:06

by Jaegeuk Kim

[permalink] [raw]
Subject: Re: [PATCH v3] f2fs: fix to do sanity check for inline inode

On 05/15, Chao Yu wrote:
> 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(-)
>
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 492af5b96de1..0dc2461ef02c 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -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;

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

> return f2fs_encrypted_file(inode) || fsverity_active(inode) ||
> f2fs_compressed_file(inode);
> }
> diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c
> index 2fce8fa0dac8..5e494c98e3c2 100644
> --- a/fs/f2fs/inode.c
> +++ b/fs/f2fs/inode.c
> @@ -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);
> --
> 2.32.0