diff options
| author | Vasant Hegde <hegdevasant@linux.vnet.ibm.com> | 2015-10-16 15:53:29 +0530 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2015-10-22 11:03:25 +1100 |
| commit | 8832317f662c06f5c06e638f57bfe89a71c9b266 (patch) | |
| tree | 31aa6635b4bdcae31e2af6566f58634d1b7fe50c /arch | |
| parent | 53c656c4138511c2ba54df413dc29976cfa9f084 (diff) | |
powerpc/rtas: Validate rtas.entry before calling enter_rtas()
Currently we do not validate rtas.entry before calling enter_rtas(). This
leads to a kernel oops when user space calls rtas system call on a powernv
platform (see below). This patch adds code to validate rtas.entry before
making enter_rtas() call.
Oops: Exception in kernel mode, sig: 4 [#1]
SMP NR_CPUS=1024 NUMA PowerNV
task: c000000004294b80 ti: c0000007e1a78000 task.ti: c0000007e1a78000
NIP: 0000000000000000 LR: 0000000000009c14 CTR: c000000000423140
REGS: c0000007e1a7b920 TRAP: 0e40 Not tainted (3.18.17-340.el7_1.pkvm3_1_0.2400.1.ppc64le)
MSR: 1000000000081000 <HV,ME> CR: 00000000 XER: 00000000
CFAR: c000000000009c0c SOFTE: 0
NIP [0000000000000000] (null)
LR [0000000000009c14] 0x9c14
Call Trace:
[c0000007e1a7bba0] [c00000000041a7f4] avc_has_perm_noaudit+0x54/0x110 (unreliable)
[c0000007e1a7bd80] [c00000000002ddc0] ppc_rtas+0x150/0x2d0
[c0000007e1a7be30] [c000000000009358] syscall_exit+0x0/0x98
Cc: stable@vger.kernel.org # v3.2+
Fixes: 55190f88789a ("powerpc: Add skeleton PowerNV platform")
Reported-by: NAGESWARA R. SASTRY <nasastry@in.ibm.com>
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
[mpe: Reword change log, trim oops, and add stable + fixes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/powerpc/kernel/rtas.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/rtas.c b/arch/powerpc/kernel/rtas.c index 84bf934cf748..5a753fae8265 100644 --- a/arch/powerpc/kernel/rtas.c +++ b/arch/powerpc/kernel/rtas.c @@ -1043,6 +1043,9 @@ asmlinkage int ppc_rtas(struct rtas_args __user *uargs) if (!capable(CAP_SYS_ADMIN)) return -EPERM; + if (!rtas.entry) + return -EINVAL; + if (copy_from_user(&args, uargs, 3 * sizeof(u32)) != 0) return -EFAULT; |