From: Alexander Aring aahringo@redhat.com
[ Upstream commit c45674fbdda138814ca21138475219c96fa5aa1f ]
While running tcpkill I experienced invalid header length values while receiving to check that a node doesn't try to send a invalid dlm message we also check on applications minimum allocation limit. Also use DEFAULT_BUFFER_SIZE as maximum allocation limit. The define LOWCOMMS_MAX_TX_BUFFER_LEN is to calculate maximum buffer limits on application layer, future midcomms layer will subtract their needs from this define.
Signed-off-by: Alexander Aring aahringo@redhat.com Signed-off-by: David Teigland teigland@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/dlm/lowcomms.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c index 0f7fa23cccf0..f827d0b3962a 100644 --- a/fs/dlm/lowcomms.c +++ b/fs/dlm/lowcomms.c @@ -1375,9 +1375,11 @@ void *dlm_lowcomms_get_buffer(int nodeid, int len, gfp_t allocation, char **ppc) struct writequeue_entry *e; int offset = 0;
- if (len > LOWCOMMS_MAX_TX_BUFFER_LEN) { - BUILD_BUG_ON(PAGE_SIZE < LOWCOMMS_MAX_TX_BUFFER_LEN); + if (len > DEFAULT_BUFFER_SIZE || + len < sizeof(struct dlm_header)) { + BUILD_BUG_ON(PAGE_SIZE < DEFAULT_BUFFER_SIZE); log_print("failed to allocate a buffer of size %d", len); + WARN_ON(1); return NULL; }