Commit 26d43a90 authored by Mathieu Desnoyers's avatar Mathieu Desnoyers Committed by Peter Zijlstra
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rseq: Clarify rseq registration rseq_size bound check comment 



The rseq registration validates that the rseq_size argument is greater
or equal to 32 (the original rseq size), but the comment associated with
this check does not clearly state this.

Clarify the comment to that effect.

Fixes: ee3e3ac0 ("rseq: Introduce extensible rseq ABI")
Signed-off-by: default avatarMathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Link: https://patch.msgid.link/20260220200642.1317826-2-mathieu.desnoyers@efficios.com
parent 5324953c

kernel/rseq.c

+3 −2
Original line number Diff line number Diff line
@@ -449,8 +449,9 @@ SYSCALL_DEFINE4(rseq, struct rseq __user *, rseq, u32, rseq_len, int, flags, u32 
	 * auxiliary vector AT_RSEQ_ALIGN. If rseq_len is the original rseq

	 * size, the required alignment is the original struct rseq alignment.

	 *

	 * In order to be valid, rseq_len is either the original rseq size, or

	 * large enough to contain all supported fields, as communicated to

	 * The rseq_len is required to be greater or equal to the original rseq

	 * size. In order to be valid, rseq_len is either the original rseq size,

	 * or large enough to contain all supported fields, as communicated to

	 * user-space through the ELF auxiliary vector AT_RSEQ_FEATURE_SIZE.

	 */

	if (rseq_len < ORIG_RSEQ_SIZE ||