The patch titled
Subject: proc: check permissions earlier for /proc/*/wchan
has been added to the -mm tree. Its filename is
proc-check-permissions-earlier-for-proc-wchan.patch
This patch should soon appear at
http://ozlabs.org/~akpm/mmots/broken-out/proc-check-permissions-earlier-for-proc-wchan.patch
and later at
http://ozlabs.org/~akpm/mmotm/broken-out/proc-check-permissions-earlier-for-proc-wchan.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
b) Prefer to cc a suitable mailing list as well
c) Ideally: find the original patch on the mailing list and do a
reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/SubmitChecklist when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Subject: proc: check permissions earlier for /proc/*/wchan
get_wchan() accesses stack page before permissions are checked, let's not
play this game.
Link: http://lkml.kernel.org/r/20180217071923.GA16074@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Reviewed-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Andy Shevchenko <andy.shevchenko@xxxxxxxxx>
Cc: Rasmus Villemoes <rasmus.villemoes@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/proc/base.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff -puN fs/proc/base.c~proc-check-permissions-earlier-for-proc-wchan fs/proc/base.c
--- a/fs/proc/base.c~proc-check-permissions-earlier-for-proc-wchan
+++ a/fs/proc/base.c
@@ -391,14 +391,17 @@ static int proc_pid_wchan(struct seq_fil
unsigned long wchan;
char symname[KSYM_NAME_LEN];
- wchan = get_wchan(task);
+ if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
+ goto print0;
- if (wchan && ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)
- && !lookup_symbol_name(wchan, symname))
+ wchan = get_wchan(task);
+ if (wchan && !lookup_symbol_name(wchan, symname)) {
seq_printf(m, "%s", symname);
- else
- seq_putc(m, '0');
+ return 0;
+ }
+print0:
+ seq_putc(m, '0');
return 0;
}
#endif /* CONFIG_KALLSYMS */
_
Patches currently in -mm which might be from adobriyan@xxxxxxxxx are
proc-do-less-stuff-under-pde_unload_lock.patch
proc-move-proc-sysvipc-creation-to-where-it-belongs.patch
proc-faster-open-close-of-files-without-release-hook.patch
proc-randomize-struct-pde_opener.patch
proc-move-struct-pde_opener-to-kmem-cache.patch
proc-account-struct-pde_opener.patch
proc-fix-proc-map_files-lookup-some-more.patch
proc-check-permissions-earlier-for-proc-wchan.patch
proc-use-set_puts-at-proc-wchan.patch
seq_file-delete-small-value-optimization.patch
--
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
