The same thing was fixed for execve() in commit 8b01fc86b9f425899f8a3a8fc1c47d73c2c20543, but for performance reasons, that simple patch won't work for stat(). --- man2/stat.2 | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/man2/stat.2 b/man2/stat.2 index 0d244af..69ec6a4 100644 --- a/man2/stat.2 +++ b/man2/stat.2 @@ -175,6 +175,29 @@ that may be present between some fields on various architectures. Consult the glibc and kernel source code if you need to know the details. +\# Background: inode attributes are modified with i_mutex held, but +\# read by stat() without taking the mutex. +.I Note: +For performance and simplicity reasons, different fields in the +.I stat +structure may contain state information from different moments +during the execution of the syscall. For example, if +.IR st_mode , +.IR st_uid +and +.IR st_gid +are changed by another process by calling +.BR chown (2) , +.BR stat () +might return the old +.I st_mode +together with the new +.IR st_uid , +or the old +.I st_uid +together with the new +.IR st_mode . + The .I st_dev field describes the device on which this file resides. -- 2.1.4
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