5.10-stable review patch. If anyone has any objections, please let me know.
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From: David Howells dhowells@redhat.com
commit acc657692aed438e9931438f8c923b2b107aebf9 upstream.
Fix the size check added to dns_resolver_preparse() for the V1 server-list header so that it doesn't give EINVAL if the size supplied is the same as the size of the header struct (which should be valid).
This can be tested with:
echo -n -e '\0\0\01\xff\0\0' | keyctl padd dns_resolver desc @p
which will give "add_key: Invalid argument" without this fix.
Fixes: 1997b3cb4217 ("keys, dns: Fix missing size check of V1 server-list header") Reported-by: Pengfei Xu pengfei.xu@intel.com Link: https://lore.kernel.org/r/ZZ4fyY4r3rqgZL+4@xpf.sh.intel.com/ Signed-off-by: David Howells dhowells@redhat.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Cc: Petr Vorel pvorel@suse.cz Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- net/dns_resolver/dns_key.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/dns_resolver/dns_key.c +++ b/net/dns_resolver/dns_key.c @@ -104,7 +104,7 @@ dns_resolver_preparse(struct key_prepars const struct dns_server_list_v1_header *v1;
/* It may be a server list. */ - if (datalen <= sizeof(*v1)) + if (datalen < sizeof(*v1)) return -EINVAL;
v1 = (const struct dns_server_list_v1_header *)data;