2022-05-09 10:49:31

by Dan Carpenter

Subject: [PATCH] fs/ntfs3: Don't clear upper bits accidentally in log_replay()

The "vcn" variable is a 64 bit. The "log->clst_per_page" variable is a
u32. This means that the mask accidentally clears out the high 32 bits
when it was only supposed to clear some low bits. Fix this by adding a
cast to u64.

Fixes: b46acd6a6a62 ("fs/ntfs3: Add NTFS journal")
Signed-off-by: Dan Carpenter <[email protected]>
---
Why am I getting new Smatch warnings in old ntfs3 code? It is a mystery.

fs/ntfs3/fslog.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c
index 915f42cf07bc..0da339fda2f4 100644
--- a/fs/ntfs3/fslog.c
+++ b/fs/ntfs3/fslog.c
@@ -5057,7 +5057,7 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
goto add_allocated_vcns;

vcn = le64_to_cpu(lrh->target_vcn);
- vcn &= ~(log->clst_per_page - 1);
+ vcn &= ~(u64)(log->clst_per_page - 1);

add_allocated_vcns:
for (i = 0, vcn = le64_to_cpu(lrh->target_vcn),
--
2.35.1

2022-05-19 04:24:36

by Namjae Jeon

Subject: Re: [PATCH] fs/ntfs3: Don't clear upper bits accidentally in log_replay()

2022-05-09 18:03 GMT+09:00, Dan Carpenter <[email protected]>:
> The "vcn" variable is a 64 bit. The "log->clst_per_page" variable is a
> u32. This means that the mask accidentally clears out the high 32 bits
> when it was only supposed to clear some low bits. Fix this by adding a
> cast to u64.
>
> Fixes: b46acd6a6a62 ("fs/ntfs3: Add NTFS journal")
> Signed-off-by: Dan Carpenter <[email protected]>
Reviewed-by: Namjae Jeon <[email protected]>

> ---
> Why am I getting new Smatch warnings in old ntfs3 code? It is a mystery.
>
> fs/ntfs3/fslog.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c
> index 915f42cf07bc..0da339fda2f4 100644
> --- a/fs/ntfs3/fslog.c
> +++ b/fs/ntfs3/fslog.c
> @@ -5057,7 +5057,7 @@ int log_replay(struct ntfs_inode *ni, bool
> *initialized)
> goto add_allocated_vcns;
>
> vcn = le64_to_cpu(lrh->target_vcn);
> - vcn &= ~(log->clst_per_page - 1);
> + vcn &= ~(u64)(log->clst_per_page - 1);
>
> add_allocated_vcns:
> for (i = 0, vcn = le64_to_cpu(lrh->target_vcn),
> --
> 2.35.1
>
>
>

2022-06-10 16:50:42

by Konstantin Komarov

Subject: Re: [PATCH] fs/ntfs3: Don't clear upper bits accidentally in log_replay()

On 5/9/22 12:03, Dan Carpenter wrote:
> The "vcn" variable is a 64 bit. The "log->clst_per_page" variable is a
> u32. This means that the mask accidentally clears out the high 32 bits
> when it was only supposed to clear some low bits. Fix this by adding a
> cast to u64.
>
> Fixes: b46acd6a6a62 ("fs/ntfs3: Add NTFS journal")
> Signed-off-by: Dan Carpenter <[email protected]>
> ---
> Why am I getting new Smatch warnings in old ntfs3 code? It is a mystery.
>
> fs/ntfs3/fslog.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ntfs3/fslog.c b/fs/ntfs3/fslog.c
> index 915f42cf07bc..0da339fda2f4 100644
> --- a/fs/ntfs3/fslog.c
> +++ b/fs/ntfs3/fslog.c
> @@ -5057,7 +5057,7 @@ int log_replay(struct ntfs_inode *ni, bool *initialized)
> goto add_allocated_vcns;
>
> vcn = le64_to_cpu(lrh->target_vcn);
> - vcn &= ~(log->clst_per_page - 1);
> + vcn &= ~(u64)(log->clst_per_page - 1);
>
> add_allocated_vcns:
> for (i = 0, vcn = le64_to_cpu(lrh->target_vcn),

Thanks for patch, applied!