diff options
| author | Nate Karstens <nate.karstens@garmin.com> | 2025-11-06 16:28:33 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-12-03 12:45:19 +0100 |
| commit | af5a7f06b63dcf37e77576818f43ffdc9fb6007f (patch) | |
| tree | efe48e92c3a32c37c8c25719068e401beca844d6 | |
| parent | b7a984e9a22f8e2d8b6e95f74c61abdb16f020dd (diff) | |
strparser: Fix signed/unsigned mismatch bug
commit 4da4e4bde1c453ac5cc2dce5def81d504ae257ee upstream.
The `len` member of the sk_buff is an unsigned int. This is cast to
`ssize_t` (a signed type) for the first sk_buff in the comparison,
but not the second sk_buff. On 32-bit systems, this can result in
an integer underflow for certain values because unsigned arithmetic
is being used.
This appears to be an oversight: if the intention was to use unsigned
arithmetic, then the first cast would have been omitted. The change
ensures both len values are cast to `ssize_t`.
The underflow causes an issue with ktls when multiple TLS PDUs are
included in a single TCP segment. The mainline kernel does not use
strparser for ktls anymore, but this is still useful for other
features that still use strparser, and for backporting.
Signed-off-by: Nate Karstens <nate.karstens@garmin.com>
Cc: stable@vger.kernel.org
Fixes: 43a0c6751a32 ("strparser: Stream parser for messages")
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Sabrina Dubroca <sd@queasysnail.net>
Link: https://patch.msgid.link/20251106222835.1871628-1-nate.karstens@garmin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | net/strparser/strparser.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/strparser/strparser.c b/net/strparser/strparser.c index cd9954c4ad80..8f0c91561518 100644 --- a/net/strparser/strparser.c +++ b/net/strparser/strparser.c @@ -238,7 +238,7 @@ static int __strp_recv(read_descriptor_t *desc, struct sk_buff *orig_skb, strp_parser_err(strp, -EMSGSIZE, desc); break; } else if (len <= (ssize_t)head->len - - skb->len - stm->strp.offset) { + (ssize_t)skb->len - stm->strp.offset) { /* Length must be into new skb (and also * greater than zero) */ |