linux-kernel - [PATCH 3.19.y-ckt 59/99] arm64: cpuinfo: Missing NULL terminator in compat_hwcap

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]

Date:	Thu,  7 Jul 2016 11:37:58 -0700
From:	Kamal Mostafa <kamal@...onical.com>
To:	linux-kernel@...r.kernel.org, stable@...r.kernel.org,
	kernel-team@...ts.ubuntu.com
Cc:	Julien Grall <julien.grall@....com>,
	Will Deacon <will.deacon@....com>,
	Kamal Mostafa <kamal@...onical.com>
Subject: [PATCH 3.19.y-ckt 59/99] arm64: cpuinfo: Missing NULL terminator in compat_hwcap_str

3.19.8-ckt23 -stable review patch.  If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Julien Grall <julien.grall@....com>

commit f228b494e56d949be8d8ea09d4f973d1979201bf upstream.

The loop that browses the array compat_hwcap_str will stop when a NULL
is encountered, however NULL is missing at the end of array. This will
lead to overrun until a NULL is found somewhere in the following memory.
In reality, this works out because the compat_hwcap2_str array tends to
follow immediately in memory, and that *is* terminated correctly.
Furthermore, the unsigned int compat_elf_hwcap is checked before
printing each capability, so we end up doing the right thing because
the size of the two arrays is less than 32. Still, this is an obvious
mistake and should be fixed.

Note for backporting: commit 12d11817eaafa414 ("arm64: Move
/proc/cpuinfo handling code") moved this code in v4.4. Prior to that
commit, the same change should be made in arch/arm64/kernel/setup.c.

Fixes: 44b82b7700d0 "arm64: Fix up /proc/cpuinfo"
Signed-off-by: Julien Grall <julien.grall@....com>
Signed-off-by: Will Deacon <will.deacon@....com>
[ kamal: backport to 4.2-stable: applied to setup.c ]
Signed-off-by: Kamal Mostafa <kamal@...onical.com>
---
 arch/arm64/kernel/setup.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/setup.c b/arch/arm64/kernel/setup.c
index 386acb8..07df3f7 100644
--- a/arch/arm64/kernel/setup.c
+++ b/arch/arm64/kernel/setup.c
@@ -491,7 +491,8 @@ static const char *compat_hwcap_str[] = {
 	"idivt",
 	"vfpd32",
 	"lpae",
-	"evtstrm"
+	"evtstrm",
+	NULL
 };

 static const char *compat_hwcap2_str[] = {
-- 
2.7.4