(RHEL-51171) sd-event: do not assert on invalid signal

[lnykryn]

The signalfd_siginfo struct is received from outside via a FD, hence assert() is not appropriate way to check it. Just do a normal runtime check.

(cherry picked from commit 7a64c5f23efbb51fe4f1229c1a8aed6dd858a0a9)

Resolves: RHEL-51171

[github-actions]

Commit validation

Tracker - RHEL-51171

The following commits meet all requirements

commit	upstream
07539d2 - sd-event: do not assert on invalid signal	systemd/systemd@7a64c5f

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Tracker validation

Success

🟢 Tracker RHEL-51171 has set desired product: rhel-10.0.beta
🟢 Tracker RHEL-51171 has set desired component: systemd
🟢 Tracker RHEL-51171 has been approved

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Pull Request validation

Failed

🔴 Failed or pending checks - build (GCC, auto)[failure],ci (fedora, rawhide, address,undefined, 1, -Og)[failure],ci (fedora, 40, 0, -Og)[failure],ci (centos, 9, 0, -Og)[failure]
🔴 Review - Missing review from a member

[dtardon]

This commit is not a fix for RHEL-51171. It's a "follow-up" for row 44. I just didn't like the use of assert() there because it's conceptually wrong.

[lnykryn]

This commit is not a fix for RHEL-51171. It's a "follow-up" for row 44. I just didn't like the use of assert() there because it's conceptually wrong.

Ups, sorry, I haven't checked the actual commit :-D