path: root/src
diff options
authorFlorian Westphal <>2021-10-17 00:56:23 +0200
committerFlorian Westphal <>2021-10-19 14:09:11 +0200
commit2139913694a9850c9160920b2c638aac4828f9bb (patch)
tree0cff62d1817f461ef531e1ec6375c5d71a696308 /src
parente632eea21f4b3d03b629a5c1ac7e776d65785873 (diff)
main: _exit() if setuid
Apparently some people think its a good idea to make nft setuid so unrivilged users can change settings. "nft -f /etc/shadow" is just one example of why this is a bad idea. Disable this. Do not print anything, fd cannot be trusted. This change intentionally doesn't affect libnftables, on the off-chance that somebody creates an suid program and knows what they're doing. Signed-off-by: Florian Westphal <>
Diffstat (limited to 'src')
1 files changed, 4 insertions, 0 deletions
diff --git a/src/main.c b/src/main.c
index 21096fc7..5847fc4a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -363,6 +363,10 @@ int main(int argc, char * const *argv)
unsigned int len;
int i, val, rc;
+ /* nftables cannot be used with setuid in a safe way. */
+ if (getuid() != geteuid())
+ _exit(111);
if (!nft_options_check(argc, argv))