From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39650) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aEVez-0006VX-9d for qemu-devel@nongnu.org; Thu, 31 Dec 2015 00:20:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aEVew-00081t-0d for qemu-devel@nongnu.org; Thu, 31 Dec 2015 00:20:25 -0500 Received: from mx1.redhat.com ([209.132.183.28]:50842) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aEVev-0007zH-OV for qemu-devel@nongnu.org; Thu, 31 Dec 2015 00:20:21 -0500 References: <1451537606-16030-1-git-send-email-ppandit@redhat.com> From: Jason Wang Message-ID: <5684BB0A.3080007@redhat.com> Date: Thu, 31 Dec 2015 13:20:10 +0800 MIME-Version: 1.0 In-Reply-To: <1451537606-16030-1-git-send-email-ppandit@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATVH v2] net: ne2000: fix bounds check in ioport operations List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: P J P Cc: Ling Liu , Prasad J Pandit , QEMU Developers On 12/31/2015 12:53 PM, P J P wrote: > From: Prasad J Pandit > > While doing ioport r/w operations, ne2000 device emulation suffers > from OOB r/w errors. Update respective array bounds check to avoid > OOB access. > > Reported-by: Ling Liu > Signed-off-by: Prasad J Pandit > --- > hw/net/ne2000.c | 28 +++++++++++++++------------- > 1 file changed, 15 insertions(+), 13 deletions(-) > > Updated as per review in > -> https://lists.gnu.org/archive/html/qemu-devel/2015-12/msg04856.html > > diff --git a/hw/net/ne2000.c b/hw/net/ne2000.c > index 010f9ef..d1f764b 100644 > --- a/hw/net/ne2000.c > +++ b/hw/net/ne2000.c > @@ -447,8 +447,7 @@ static uint32_t ne2000_ioport_read(void *opaque, uint32_t addr) > static inline void ne2000_mem_writeb(NE2000State *s, uint32_t addr, > uint32_t val) > { > - if (addr < 32 || > - (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { > + if (addr < 32 || (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { The change is unnecessary. > s->mem[addr] = val; > } > } > @@ -457,9 +456,10 @@ static inline void ne2000_mem_writew(NE2000State *s, uint32_t addr, > uint32_t val) > { > addr &= ~1; /* XXX: check exact behaviour if not even */ > - if (addr < 32 || > - (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { > - *(uint16_t *)(s->mem + addr) = cpu_to_le16(val); > + if (addr < 32 > + || (addr >= NE2000_PMEM_START > + && addr + sizeof(uint16_t) < NE2000_MEM_SIZE)) { I think you mean '<=' instead of '<' here? (And for the other checks below). > + *(uint16_t *)(s->mem + addr) = cpu_to_le16(data); > } > } > > @@ -467,16 +467,16 @@ static inline void ne2000_mem_writel(NE2000State *s, uint32_t addr, > uint32_t val) > { > addr &= ~1; /* XXX: check exact behaviour if not even */ > - if (addr < 32 || > - (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { > + if (addr < 32 > + || (addr >= NE2000_PMEM_START > + && addr + sizeof(uint32_t) < NE2000_MEM_SIZE)) { > stl_le_p(s->mem + addr, val); > } > } > > static inline uint32_t ne2000_mem_readb(NE2000State *s, uint32_t addr) > { > - if (addr < 32 || > - (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { > + if (addr < 32 || (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { > return s->mem[addr]; > } else { > return 0xff; > @@ -486,8 +486,9 @@ static inline uint32_t ne2000_mem_readb(NE2000State *s, uint32_t addr) > static inline uint32_t ne2000_mem_readw(NE2000State *s, uint32_t addr) > { > addr &= ~1; /* XXX: check exact behaviour if not even */ > - if (addr < 32 || > - (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { > + if (addr < 32 > + || (addr >= NE2000_PMEM_START > + && addr + sizeof(uint16_t) < NE2000_MEM_SIZE)) { > return le16_to_cpu(*(uint16_t *)(s->mem + addr)); > } else { > return 0xffff; > @@ -497,8 +498,9 @@ static inline uint32_t ne2000_mem_readw(NE2000State *s, uint32_t addr) > static inline uint32_t ne2000_mem_readl(NE2000State *s, uint32_t addr) > { > addr &= ~1; /* XXX: check exact behaviour if not even */ > - if (addr < 32 || > - (addr >= NE2000_PMEM_START && addr < NE2000_MEM_SIZE)) { > + if (addr < 32 > + || (addr >= NE2000_PMEM_START > + && addr + sizeof(uint32_t) < NE2000_MEM_SIZE)) { > return ldl_le_p(s->mem + addr); > } else { > return 0xffffffff;