diff options
| author |   Ömer Mete Kaya <omermetekaya0@gmail.com> | 2026-09-08 19:18:01 +0300 |
|---|---|---|
| committer |   David Heidelberg <david@ixit.cz> | 2026-09-23 22:13:17 +0200 |
| commit | 7dcf371a35632f035baf77bcf2c129165f772ce4 (patch) | |
| tree | 7105f89798bbfdb1655699aedc0d3965cd2a0c1d | |
| parent | nfc: llcp: fix WKS SAP hijacking via prefix match in nfc_llcp_wks_sap() (diff) | |
nfc: llcp: fix slab-out-of-bounds reads when logging service names
nfc_llcp_wks_sap() and nfc_llcp_build_sdreq_tlv() pass non-null-
terminated strings to pr_debug() using the %s format specifier.
The buffers are allocated via kmemdup() or come from netlink
attributes and are not guaranteed to be null-terminated, causing
__dynamic_pr_debug() to read beyond the allocated region:
KASAN: slab-out-of-bounds Read in __dynamic_pr_debug
Fix both call sites by using %.*s with the explicit length to limit
the output to the actual length of the string.
Fixes: d9b8d8e19b07 ("NFC: llcp: Service Name Lookup netlink interface")
Reported-by: syzbot+1e3df0852e82c21ca418@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1e3df0852e82c21ca418
Signed-off-by: Ömer Mete Kaya <omermetekaya0@gmail.com>
Link: https://patch.msgid.link/20260908161952.731468-1-omermetekaya0@gmail.com
Signed-off-by: David Heidelberg <david@ixit.cz>
| -rw-r--r-- | net/nfc/llcp_commands.c | 2 | ||||
| -rw-r--r-- | net/nfc/llcp_core.c | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/net/nfc/llcp_commands.c b/net/nfc/llcp_commands.c index ca89fe967d6a..80a00938c869 100644 --- a/net/nfc/llcp_commands.c +++ b/net/nfc/llcp_commands.c @@ -135,7 +135,7 @@ struct nfc_llcp_sdp_tlv *nfc_llcp_build_sdreq_tlv(u8 tid, const char *uri, { struct nfc_llcp_sdp_tlv *sdreq; - pr_debug("uri: %s, len: %zu\n", uri, uri_len); + pr_debug("uri: %.*s, len: %zu\n", (int)uri_len, uri, uri_len); /* sdreq->tlv_len is u8, takes uri_len, + 3 for header, + 1 for NULL */ if (WARN_ON_ONCE(uri_len > U8_MAX - 4)) diff --git a/net/nfc/llcp_core.c b/net/nfc/llcp_core.c index def712e1b2b2..74bf817007cf 100644 --- a/net/nfc/llcp_core.c +++ b/net/nfc/llcp_core.c @@ -358,7 +358,7 @@ static int nfc_llcp_wks_sap(const char *service_name, size_t service_name_len) { int sap, num_wks; - pr_debug("%s\n", service_name); + pr_debug("%.*s\n", (int)service_name_len, service_name); if (service_name == NULL) return -EINVAL; |