| Message ID | c8e8f0326a3993792a65125fa200965e8a4580e4.1727795385.git.sd@queasysnail.net (mailing list archive) |
|---|---|
| State | Awaiting Upstream |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [ipsec] xfrm: validate new SA's prefixlen using SA family when sel.family is unset | expand |
On Tue, Oct 01, 2024 at 06:48:14PM +0200, Sabrina Dubroca wrote: > This expands the validation introduced in commit 07bf7908950a ("xfrm: > Validate address prefix lengths in the xfrm selector.") > > syzbot created an SA with > usersa.sel.family = AF_UNSPEC > usersa.sel.prefixlen_s = 128 > usersa.family = AF_INET > > Because of the AF_UNSPEC selector, verify_newsa_info doesn't put > limits on prefixlen_{s,d}. But then copy_from_user_state sets > x->sel.family to usersa.family (AF_INET). Do the same conversion in > verify_newsa_info before validating prefixlen_{s,d}, since that's how > prefixlen is going to be used later on. > > Reported-by: syzbot+cc39f136925517aed571@syzkaller.appspotmail.com > Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") > Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Applied, thanks a lot Sabrina!
diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 55f039ec3d59..8d06a37adbd9 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -201,6 +201,7 @@ static int verify_newsa_info(struct xfrm_usersa_info *p, { int err; u8 sa_dir = attrs[XFRMA_SA_DIR] ? nla_get_u8(attrs[XFRMA_SA_DIR]) : 0; + u16 family = p->sel.family; err = -EINVAL; switch (p->family) { @@ -221,7 +222,10 @@ static int verify_newsa_info(struct xfrm_usersa_info *p, goto out; } - switch (p->sel.family) { + if (!family && !(p->flags & XFRM_STATE_AF_UNSPEC)) + family = p->family; + + switch (family) { case AF_UNSPEC: break;
This expands the validation introduced in commit 07bf7908950a ("xfrm: Validate address prefix lengths in the xfrm selector.") syzbot created an SA with usersa.sel.family = AF_UNSPEC usersa.sel.prefixlen_s = 128 usersa.family = AF_INET Because of the AF_UNSPEC selector, verify_newsa_info doesn't put limits on prefixlen_{s,d}. But then copy_from_user_state sets x->sel.family to usersa.family (AF_INET). Do the same conversion in verify_newsa_info before validating prefixlen_{s,d}, since that's how prefixlen is going to be used later on. Reported-by: syzbot+cc39f136925517aed571@syzkaller.appspotmail.com Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> --- net/xfrm/xfrm_user.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)