remove sprintf usage

Summary

In the Linux kernel, the following vulnerability has been resolved: netfilter: conntrack: remove sprintf usage Replace it with scnprintf, the buffer sizes are expected to be large enough to hold the result, no need for snprintf+overflow check. Increase buffer size in mangle_content_len() while at it. BUG: KASAN: stack-out-of-bounds in vsnprintf+0xea5/0x1270 Write of size 1 at addr [..] vsnprintf+0xea5/0x1270 sprintf+0xb1/0xe0 mangle_content_len+0x1ac/0x280 nf_nat_sdp_session+0x1cc/0x240 process_sdp+0x8f8/0xb80 process_invite_request+0x108/0x2b0 process_sip_msg+0x5da/0xf50 sip_help_tcp+0x45e/0x780 nf_confirm+0x34d/0x990 [..] A flaw was found in the Linux kernel's netfilter conntrack module. This vulnerability arises from the use of `sprintf` and insufficient buffer sizing in the `mangle_content_len()` function, which can lead to a stack-out-of-bounds write. An attacker could potentially exploit this memory corruption issue to cause a denial of service or other unspecified impacts. Red Hat severity: Important — CVSS 7 (CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H). Weakness: CWE-787. No fixing RHSA erratum has published yet; monitor the Red Hat CVE page and patch when it ships.