[PATCH] man/man2/link.2: Document new AT_EMPTY_PATH behavior

From: Runxi Yu <[email protected]>

Signed-off-by: Runxi Yu <[email protected]>
---
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recipient.

 man/man2/link.2 | 32 +++++++++++++++++++++++++++-----
 1 file changed, 27 insertions(+), 5 deletions(-)

diff --git a/man/man2/link.2 b/man/man2/link.2
index effed3f74..a888da919 100644
--- a/man/man2/link.2
+++ b/man/man2/link.2
@@ -115,9 +115,30 @@ created with
 and without
 .B O_EXCL
 are an exception).
-The caller must have the
+.\" commit 42bd2af5950456d46fdaa91c3a8fb02e680f19f5
+Since Linux 6.10,
+no privilege is required to use this flag if the credentials under which
+.I olddirfd
+was opened match the caller's current credentials
+(as is normally the case when the caller opened
+.I olddirfd
+itself and has not since altered its credentials).
+Otherwise
+(for example, when
+.I olddirfd
+was received from another process,
+or the caller's credentials have changed since
+.I olddirfd
+was opened),
+the caller must have the
 .B CAP_DAC_READ_SEARCH
-capability in order to use this flag.
+capability in the user namespace of the credentials under which
+.I olddirfd
+was opened.
+Before Linux 6.10,
+the
+.B CAP_DAC_READ_SEARCH
+capability was required in all cases.
 This flag is Linux-specific;
 define
 .B _GNU_SOURCE
@@ -281,9 +302,10 @@ An invalid flag value was specified in
 .B AT_EMPTY_PATH
 was specified in
 .IR flags ,
-but the caller did not have the
-.B CAP_DAC_READ_SEARCH
-capability.
+but the caller lacked the privilege required to create the link;
+see the description of
+.B AT_EMPTY_PATH
+above.
 .TP
 .B ENOENT
 An attempt was made to link to the
-- 
2.55.0