From: <gregkh@linuxfoundation.org>
To: vapier@gentoo.org, davem@davemloft.net, gregkh@linuxfoundation.org
Cc: <stable@vger.kernel.org>, <stable-commits@vger.kernel.org>
Subject: Patch "sparc: Fix system call tracing register handling." has been added to the 4.4-stable tree
Date: Mon, 20 Jun 2016 10:48:49 -0700 [thread overview]
Message-ID: <146644492956230@kroah.com> (raw)
This is a note to let you know that I've just added the patch titled
sparc: Fix system call tracing register handling.
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
sparc-fix-system-call-tracing-register-handling.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.
>From foo@baz Mon Jun 20 10:48:29 PDT 2016
From: Mike Frysinger <vapier@gentoo.org>
Date: Mon, 18 Jan 2016 06:32:30 -0500
Subject: sparc: Fix system call tracing register handling.
From: Mike Frysinger <vapier@gentoo.org>
[ Upstream commit 1a40b95374f680625318ab61d81958e949e0afe3 ]
A system call trace trigger on entry allows the tracing
process to inspect and potentially change the traced
process's registers.
Account for that by reloading the %g1 (syscall number)
and %i0-%i5 (syscall argument) values. We need to be
careful to revalidate the range of %g1, and reload the
system call table entry it corresponds to into %l7.
Reported-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
arch/sparc/kernel/entry.S | 17 +++++++++++++++++
arch/sparc/kernel/syscalls.S | 36 ++++++++++++++++++++++++++++++++++++
2 files changed, 53 insertions(+)
--- a/arch/sparc/kernel/entry.S
+++ b/arch/sparc/kernel/entry.S
@@ -948,7 +948,24 @@ linux_syscall_trace:
cmp %o0, 0
bne 3f
mov -ENOSYS, %o0
+
+ /* Syscall tracing can modify the registers. */
+ ld [%sp + STACKFRAME_SZ + PT_G1], %g1
+ sethi %hi(sys_call_table), %l7
+ ld [%sp + STACKFRAME_SZ + PT_I0], %i0
+ or %l7, %lo(sys_call_table), %l7
+ ld [%sp + STACKFRAME_SZ + PT_I1], %i1
+ ld [%sp + STACKFRAME_SZ + PT_I2], %i2
+ ld [%sp + STACKFRAME_SZ + PT_I3], %i3
+ ld [%sp + STACKFRAME_SZ + PT_I4], %i4
+ ld [%sp + STACKFRAME_SZ + PT_I5], %i5
+ cmp %g1, NR_syscalls
+ bgeu 3f
+ mov -ENOSYS, %o0
+
+ sll %g1, 2, %l4
mov %i0, %o0
+ ld [%l7 + %l4], %l7
mov %i1, %o1
mov %i2, %o2
mov %i3, %o3
--- a/arch/sparc/kernel/syscalls.S
+++ b/arch/sparc/kernel/syscalls.S
@@ -158,7 +158,25 @@ linux_syscall_trace32:
add %sp, PTREGS_OFF, %o0
brnz,pn %o0, 3f
mov -ENOSYS, %o0
+
+ /* Syscall tracing can modify the registers. */
+ ldx [%sp + PTREGS_OFF + PT_V9_G1], %g1
+ sethi %hi(sys_call_table32), %l7
+ ldx [%sp + PTREGS_OFF + PT_V9_I0], %i0
+ or %l7, %lo(sys_call_table32), %l7
+ ldx [%sp + PTREGS_OFF + PT_V9_I1], %i1
+ ldx [%sp + PTREGS_OFF + PT_V9_I2], %i2
+ ldx [%sp + PTREGS_OFF + PT_V9_I3], %i3
+ ldx [%sp + PTREGS_OFF + PT_V9_I4], %i4
+ ldx [%sp + PTREGS_OFF + PT_V9_I5], %i5
+
+ cmp %g1, NR_syscalls
+ bgeu,pn %xcc, 3f
+ mov -ENOSYS, %o0
+
+ sll %g1, 2, %l4
srl %i0, 0, %o0
+ lduw [%l7 + %l4], %l7
srl %i4, 0, %o4
srl %i1, 0, %o1
srl %i2, 0, %o2
@@ -170,7 +188,25 @@ linux_syscall_trace:
add %sp, PTREGS_OFF, %o0
brnz,pn %o0, 3f
mov -ENOSYS, %o0
+
+ /* Syscall tracing can modify the registers. */
+ ldx [%sp + PTREGS_OFF + PT_V9_G1], %g1
+ sethi %hi(sys_call_table64), %l7
+ ldx [%sp + PTREGS_OFF + PT_V9_I0], %i0
+ or %l7, %lo(sys_call_table64), %l7
+ ldx [%sp + PTREGS_OFF + PT_V9_I1], %i1
+ ldx [%sp + PTREGS_OFF + PT_V9_I2], %i2
+ ldx [%sp + PTREGS_OFF + PT_V9_I3], %i3
+ ldx [%sp + PTREGS_OFF + PT_V9_I4], %i4
+ ldx [%sp + PTREGS_OFF + PT_V9_I5], %i5
+
+ cmp %g1, NR_syscalls
+ bgeu,pn %xcc, 3f
+ mov -ENOSYS, %o0
+
+ sll %g1, 2, %l4
mov %i0, %o0
+ lduw [%l7 + %l4], %l7
mov %i1, %o1
mov %i2, %o2
mov %i3, %o3
Patches currently in stable-queue which might be from vapier@gentoo.org are
queue-4.4/sparc-fix-system-call-tracing-register-handling.patch
reply other threads:[~2016-06-20 17:56 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=146644492956230@kroah.com \
--to=gregkh@linuxfoundation.org \
--cc=davem@davemloft.net \
--cc=stable-commits@vger.kernel.org \
--cc=stable@vger.kernel.org \
--cc=vapier@gentoo.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).