2025-11-06, 16:28:33 -0600, Nate Karstens wrote:
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")
net/strparser/strparser.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
Reviewed-by: Sabrina Dubroca sd@queasysnail.net
Thanks Nate.