linux-kernel - [PATCH 3.10 28/35] ARM: Fix FIQ code on VIVT CPUs

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20150814174354.741370239@linuxfoundation.org>
Date:	Fri, 14 Aug 2015 10:45:06 -0700
From:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:	linux-kernel@...r.kernel.org
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	stable@...r.kernel.org, Aaro Koskinen <aaro.koskinen@....fi>,
	Russell King <rmk+kernel@....linux.org.uk>,
	Martin Kaiser <lists@...ser.cx>
Subject: [PATCH 3.10 28/35] ARM: Fix FIQ code on VIVT CPUs

3.10-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Russell King <rmk+kernel@....linux.org.uk>

commit 2ba85e7af4c639d933c9a87a6d7363f2983d5ada upstream.

Aaro Koskinen reports the following oops:
Installing fiq handler from c001b110, length 0x164
Unable to handle kernel paging request at virtual address ffff1224
pgd = c0004000
[ffff1224] *pgd=00000000, *pte=11fff0cb, *ppte=11fff00a
...
[<c0013154>] (set_fiq_handler+0x0/0x6c) from [<c0365d38>] (ams_delta_init_fiq+0xa8/0x160)
 r6:00000164 r5:c001b110 r4:00000000 r3:fefecb4c
[<c0365c90>] (ams_delta_init_fiq+0x0/0x160) from [<c0365b14>] (ams_delta_init+0xd4/0x114)
 r6:00000000 r5:fffece10 r4:c037a9e0
[<c0365a40>] (ams_delta_init+0x0/0x114) from [<c03613b4>] (customize_machine+0x24/0x30)

This is because the vectors page is now write-protected, and to change
code in there we must write to its original alias.  Make that change,
and adjust the cache flushing such that the code will become visible
to the instruction stream on VIVT CPUs.

Reported-by: Aaro Koskinen <aaro.koskinen@....fi>
Tested-by: Aaro Koskinen <aaro.koskinen@....fi>
Signed-off-by: Russell King <rmk+kernel@....linux.org.uk>
Cc: Martin Kaiser <lists@...ser.cx>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 arch/arm/kernel/fiq.c |    8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

--- a/arch/arm/kernel/fiq.c
+++ b/arch/arm/kernel/fiq.c
@@ -84,17 +84,13 @@ int show_fiq_list(struct seq_file *p, in
 
 void set_fiq_handler(void *start, unsigned int length)
 {
-#if defined(CONFIG_CPU_USE_DOMAINS)
-	void *base = (void *)0xffff0000;
-#else
 	void *base = vectors_page;
-#endif
 	unsigned offset = FIQ_OFFSET;
 
 	memcpy(base + offset, start, length);
+	if (!cache_is_vipt_nonaliasing())
+		flush_icache_range(base + offset, offset + length);
 	flush_icache_range(0xffff0000 + offset, 0xffff0000 + offset + length);
-	if (!vectors_high())
-		flush_icache_range(offset, offset + length);
 }
 
 int claim_fiq(struct fiq_handler *f)


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/