Description: bpf: Fix toctou on read-only map's constant scalar tracking
References:
 https://bugzilla.redhat.com/show_bug.cgi?id=2025645
 https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git/commit/?id=353050be4c19e102178ccc05988101887c25ae53
Notes:
 carnil> Commit fixes a23740ec43ba ("bpf: Track contents of read-only
 carnil> maps as scalars") introduced in 5.5-rc1.
 carnil> For 5.15.y series fixed in 5.15.5.
Bugs:
upstream: released (5.16-rc2) [353050be4c19e102178ccc05988101887c25ae53]
5.10-upstream-stable: released (5.10.83) [33fe044f6a9e8977686a6a09f0bf33e5cc75257e]
4.19-upstream-stable: N/A "Vulnerable code introduced later"
4.9-upstream-stable: N/A "Vulnerable code introduced later"
sid: released (5.15.5-1)
5.10-bullseye-security: released (5.10.84-1)
4.19-buster-security: N/A "Vulnerable code introduced later"
4.9-stretch-security: N/A "Vulnerable code introduced later"