lkml.org 
[lkml]   [2022]   [Dec]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH] Bluetooth: Fix a buffer overflow in mgmt_mesh_add()
    Date
    Smatch Warning:
    net/bluetooth/mgmt_util.c:375 mgmt_mesh_add() error: __memcpy()
    'mesh_tx->param' too small (48 vs 50)

    Analysis:

    'mesh_tx->param' is array of size 48. This is the destination.
    u8 param[sizeof(struct mgmt_cp_mesh_send) + 29]; // 19 + 29 = 48.

    But in the caller 'mesh_send' we reject only when len > 50.
    len > (MGMT_MESH_SEND_SIZE + 31) // 19 + 31 = 50.

    Fixes: b338d91703fa ("Bluetooth: Implement support for Mesh")
    Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
    ---
    This is based on static analysis, I am unsure if we should put
    an upper bound to len(48) instead.

    This limit on length changed between v4 and v5 patches of Commit:
    ("Bluetooth: Implement support for Mesh") in function mesh_send()

    v4: https://lore.kernel.org/all/20220511155412.740249-2-brian.gix@intel.com/
    v5: https://lore.kernel.org/all/20220720194511.320773-2-brian.gix@intel.com/
    ---
    net/bluetooth/mgmt_util.h | 2 +-
    1 file changed, 1 insertion(+), 1 deletion(-)

    diff --git a/net/bluetooth/mgmt_util.h b/net/bluetooth/mgmt_util.h
    index 6a8b7e84293d..bdf978605d5a 100644
    --- a/net/bluetooth/mgmt_util.h
    +++ b/net/bluetooth/mgmt_util.h
    @@ -27,7 +27,7 @@ struct mgmt_mesh_tx {
    struct sock *sk;
    u8 handle;
    u8 instance;
    - u8 param[sizeof(struct mgmt_cp_mesh_send) + 29];
    + u8 param[sizeof(struct mgmt_cp_mesh_send) + 31];
    };

    struct mgmt_pending_cmd {
    --
    2.38.1
    \
     
     \ /
      Last update: 2022-12-12 14:09    [W:3.338 / U:0.012 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site