diff mbox series

[SRU,H/I/OEM-5.14] NFSD: Fix exposure in nfsd4_decode_bitmap()

Message ID 20211216200638.935463-1-cascardo@canonical.com
State Accepted
Headers show
Series [SRU,H/I/OEM-5.14] NFSD: Fix exposure in nfsd4_decode_bitmap() | expand

Commit Message

Thadeu Lima de Souza Cascardo Dec. 16, 2021, 8:06 p.m. UTC 
From: Chuck Lever <chuck.lever@oracle.com>

rtm@csail.mit.edu reports:
> nfsd4_decode_bitmap4() will write beyond bmval[bmlen-1] if the RPC
> directs it to do so. This can cause nfsd4_decode_state_protect4_a()
> to write client-supplied data beyond the end of
> nfsd4_exchange_id.spo_must_allow[] when called by
> nfsd4_decode_exchange_id().

Rewrite the loops so nfsd4_decode_bitmap() cannot iterate beyond
@bmlen.

Reported by: rtm@csail.mit.edu
Fixes: d1c263a031e8 ("NFSD: Replace READ* macros in nfsd4_decode_fattr()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
(cherry picked from commit c0019b7db1d7ac62c711cda6b357a659d46428fe)
CVE-2021-4090
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
---
 fs/nfsd/nfs4xdr.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

Comments

Tim Gardner Dec. 17, 2021, 12:40 p.m. UTC | #1 
Acked-by: Tim Gardner <tim.gardner@canonical.com>

On 12/16/21 1:06 PM, Thadeu Lima de Souza Cascardo wrote:
> From: Chuck Lever <chuck.lever@oracle.com>
> 
> rtm@csail.mit.edu reports:
>> nfsd4_decode_bitmap4() will write beyond bmval[bmlen-1] if the RPC
>> directs it to do so. This can cause nfsd4_decode_state_protect4_a()
>> to write client-supplied data beyond the end of
>> nfsd4_exchange_id.spo_must_allow[] when called by
>> nfsd4_decode_exchange_id().
> 
> Rewrite the loops so nfsd4_decode_bitmap() cannot iterate beyond
> @bmlen.
> 
> Reported by: rtm@csail.mit.edu
> Fixes: d1c263a031e8 ("NFSD: Replace READ* macros in nfsd4_decode_fattr()")
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
> (cherry picked from commit c0019b7db1d7ac62c711cda6b357a659d46428fe)
> CVE-2021-4090
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> ---
>   fs/nfsd/nfs4xdr.c | 7 ++-----
>   1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index be64d3f5e411..0017da5bf23f 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -288,11 +288,8 @@ nfsd4_decode_bitmap4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen)
>   	p = xdr_inline_decode(argp->xdr, count << 2);
>   	if (!p)
>   		return nfserr_bad_xdr;
> -	i = 0;
> -	while (i < count)
> -		bmval[i++] = be32_to_cpup(p++);
> -	while (i < bmlen)
> -		bmval[i++] = 0;
> +	for (i = 0; i < bmlen; i++)
> +		bmval[i] = (i < count) ? be32_to_cpup(p++) : 0;
>   
>   	return nfs_ok;
>   }
>
Kelsey Skunberg Dec. 17, 2021, 7:18 p.m. UTC | #2 
Acked-by: Kelsey Skunberg <kelsey.skunberg@canonical.com>

On 2021-12-16 17:06:38 , Thadeu Lima de Souza Cascardo wrote:
> From: Chuck Lever <chuck.lever@oracle.com>
> 
> rtm@csail.mit.edu reports:
> > nfsd4_decode_bitmap4() will write beyond bmval[bmlen-1] if the RPC
> > directs it to do so. This can cause nfsd4_decode_state_protect4_a()
> > to write client-supplied data beyond the end of
> > nfsd4_exchange_id.spo_must_allow[] when called by
> > nfsd4_decode_exchange_id().
> 
> Rewrite the loops so nfsd4_decode_bitmap() cannot iterate beyond
> @bmlen.
> 
> Reported by: rtm@csail.mit.edu
> Fixes: d1c263a031e8 ("NFSD: Replace READ* macros in nfsd4_decode_fattr()")
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
> (cherry picked from commit c0019b7db1d7ac62c711cda6b357a659d46428fe)
> CVE-2021-4090
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> ---
>  fs/nfsd/nfs4xdr.c | 7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index be64d3f5e411..0017da5bf23f 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -288,11 +288,8 @@ nfsd4_decode_bitmap4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen)
>  	p = xdr_inline_decode(argp->xdr, count << 2);
>  	if (!p)
>  		return nfserr_bad_xdr;
> -	i = 0;
> -	while (i < count)
> -		bmval[i++] = be32_to_cpup(p++);
> -	while (i < bmlen)
> -		bmval[i++] = 0;
> +	for (i = 0; i < bmlen; i++)
> +		bmval[i] = (i < count) ? be32_to_cpup(p++) : 0;
>  
>  	return nfs_ok;
>  }
> -- 
> 2.32.0
> 
> 
> -- 
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team
Kelsey Skunberg Dec. 17, 2021, 7:45 p.m. UTC | #3 
Applied to master-next for hirsute and impish. Thank you! 

-Kelsey

On 2021-12-16 17:06:38 , Thadeu Lima de Souza Cascardo wrote:
> From: Chuck Lever <chuck.lever@oracle.com>
> 
> rtm@csail.mit.edu reports:
> > nfsd4_decode_bitmap4() will write beyond bmval[bmlen-1] if the RPC
> > directs it to do so. This can cause nfsd4_decode_state_protect4_a()
> > to write client-supplied data beyond the end of
> > nfsd4_exchange_id.spo_must_allow[] when called by
> > nfsd4_decode_exchange_id().
> 
> Rewrite the loops so nfsd4_decode_bitmap() cannot iterate beyond
> @bmlen.
> 
> Reported by: rtm@csail.mit.edu
> Fixes: d1c263a031e8 ("NFSD: Replace READ* macros in nfsd4_decode_fattr()")
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
> (cherry picked from commit c0019b7db1d7ac62c711cda6b357a659d46428fe)
> CVE-2021-4090
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> ---
>  fs/nfsd/nfs4xdr.c | 7 ++-----
>  1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index be64d3f5e411..0017da5bf23f 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -288,11 +288,8 @@ nfsd4_decode_bitmap4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen)
>  	p = xdr_inline_decode(argp->xdr, count << 2);
>  	if (!p)
>  		return nfserr_bad_xdr;
> -	i = 0;
> -	while (i < count)
> -		bmval[i++] = be32_to_cpup(p++);
> -	while (i < bmlen)
> -		bmval[i++] = 0;
> +	for (i = 0; i < bmlen; i++)
> +		bmval[i] = (i < count) ? be32_to_cpup(p++) : 0;
>  
>  	return nfs_ok;
>  }
> -- 
> 2.32.0
> 
> 
> -- 
> kernel-team mailing list
> kernel-team@lists.ubuntu.com
> https://lists.ubuntu.com/mailman/listinfo/kernel-team
Timo Aaltonen Jan. 4, 2022, 9:47 a.m. UTC | #4 
On 16.12.2021 22.06, Thadeu Lima de Souza Cascardo wrote:
> From: Chuck Lever <chuck.lever@oracle.com>
> 
> rtm@csail.mit.edu reports:
>> nfsd4_decode_bitmap4() will write beyond bmval[bmlen-1] if the RPC
>> directs it to do so. This can cause nfsd4_decode_state_protect4_a()
>> to write client-supplied data beyond the end of
>> nfsd4_exchange_id.spo_must_allow[] when called by
>> nfsd4_decode_exchange_id().
> 
> Rewrite the loops so nfsd4_decode_bitmap() cannot iterate beyond
> @bmlen.
> 
> Reported by: rtm@csail.mit.edu
> Fixes: d1c263a031e8 ("NFSD: Replace READ* macros in nfsd4_decode_fattr()")
> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
> (cherry picked from commit c0019b7db1d7ac62c711cda6b357a659d46428fe)
> CVE-2021-4090
> Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
> ---
>   fs/nfsd/nfs4xdr.c | 7 ++-----
>   1 file changed, 2 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
> index be64d3f5e411..0017da5bf23f 100644
> --- a/fs/nfsd/nfs4xdr.c
> +++ b/fs/nfsd/nfs4xdr.c
> @@ -288,11 +288,8 @@ nfsd4_decode_bitmap4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen)
>   	p = xdr_inline_decode(argp->xdr, count << 2);
>   	if (!p)
>   		return nfserr_bad_xdr;
> -	i = 0;
> -	while (i < count)
> -		bmval[i++] = be32_to_cpup(p++);
> -	while (i < bmlen)
> -		bmval[i++] = 0;
> +	for (i = 0; i < bmlen; i++)
> +		bmval[i] = (i < count) ? be32_to_cpup(p++) : 0;
>   
>   	return nfs_ok;
>   }
> 

applied to oem-5.14, thanks
diff mbox series

Patch

diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index be64d3f5e411..0017da5bf23f 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -288,11 +288,8 @@  nfsd4_decode_bitmap4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen)
 	p = xdr_inline_decode(argp->xdr, count << 2);
 	if (!p)
 		return nfserr_bad_xdr;
-	i = 0;
-	while (i < count)
-		bmval[i++] = be32_to_cpup(p++);
-	while (i < bmlen)
-		bmval[i++] = 0;
+	for (i = 0; i < bmlen; i++)
+		bmval[i] = (i < count) ? be32_to_cpup(p++) : 0;
 
 	return nfs_ok;
 }