git: d3b0843d2cec - stable/15 - ipfilter: Plug ip_nat kernel information leak

The branch stable/15 has been updated by cy:

URL: https://cgit.FreeBSD.org/src/commit/?id=d3b0843d2cec1650e837c421e39532db24d49714

commit d3b0843d2cec1650e837c421e39532db24d49714
Author:     Cy Schubert <cy@FreeBSD.org>
AuthorDate: 2025-10-22 15:59:26 +0000
Commit:     Cy Schubert <cy@FreeBSD.org>
CommitDate: 2025-10-26 03:14:08 +0000

    ipfilter: Plug ip_nat kernel information leak
    
    ipf_nat_getent() allocates a variable-sized nat_save_t buffer with
    KMALLOCS() (which does not zero memory) and then copies only a subset
    of fields into it before returning the object to userland using
    ipf_outobjsz(). Because the structure is not fully initialized on all
    paths, uninitialized kernel heap bytes can be copied back to user space,
    resulting in an information leak.
    
    We fix this by zeroing out the data structure immediately after
    allocation.
    
    Reported by:            Ilja Van Sprundel <ivansprundel@ioactive.com>
    Reviewed by:            emaste
    Differential revision:  https://reviews.freebsd.org/D53274
    
    (cherry picked from commit 6535e9308a26e17023831fe68fb71d2febf2a002)
---
 sys/netpfil/ipfilter/netinet/ip_nat.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/sys/netpfil/ipfilter/netinet/ip_nat.c b/sys/netpfil/ipfilter/netinet/ip_nat.c
index 972511f43bd5..53c180cdfbca 100644
--- a/sys/netpfil/ipfilter/netinet/ip_nat.c
+++ b/sys/netpfil/ipfilter/netinet/ip_nat.c
@@ -1771,6 +1771,7 @@ ipf_nat_getent(ipf_main_softc_t *softc, caddr_t data, int getlock)
 		IPFERROR(60029);
 		return (ENOMEM);
 	}
+	bzero(ipn, ipns.ipn_dsize);
 
 	if (getlock) {
 		READ_ENTER(&softc->ipf_nat);