On Thu, 1 Mar 2007 11:33:05 -0800 [EMAIL PROTECTED] wrote: > http://bugzilla.kernel.org/show_bug.cgi?id=8107 > > Summary: dev->header_cache_update has a random value > Kernel Version: 2.6.20 > Status: NEW > Severity: high > Owner: [EMAIL PROTECTED] > Submitter: [EMAIL PROTECTED] > > > Distribution: Kernel 2.6.20 > > Problem Description: > > In struct net_device, there are two fields: hard_header_cache and > header_cache_update, both of which are function pointers. The third field, > hard_header, is also a function pointer. Whenever hard_header points to a > valid > function, both hard_header_cache and header_cache_update should have a known > value, either NULL or a valid function pointer. However, in > drivers/net/wan/hdlc_cisco.c, in function static int cisco_ioctl(struct > net_device *dev, struct ifreq *ifr), where dev->hard_header is assigned a > valid > function, and dev->hard_header_cache is assigned a known value (NULL), dev- > >header_cache_update is not set to a known value: > > dev->hard_start_xmit = hdlc->xmit; > dev->hard_header = cisco_hard_header; > dev->hard_header_cache = NULL; > dev->type = ARPHRD_CISCO; > dev->flags = IFF_POINTOPOINT | IFF_NOARP; > dev->addr_len = 0; > > This may cause serious problems when dev->header_cache_update is invoked, > because it has an uninitialized value. > > Steps to reproduce: > > I found this suspicious spot with the help of a code-checking tool. >
Like this? From: Andrew Morton <[EMAIL PROTECTED]> Fix http://bugzilla.kernel.org/show_bug.cgi?id=8107: we weren't initialising the header_cache_update field. Cc: Krzysztof Halasa <[EMAIL PROTECTED]> Cc: "David S. Miller" <[EMAIL PROTECTED]> Signed-off-by: Andrew Morton <[EMAIL PROTECTED]> --- drivers/net/wan/hdlc_cisco.c | 1 + 1 files changed, 1 insertion(+) diff -puN drivers/net/wan/hdlc_cisco.c~cisco_ioctl-initialise-header_cache_update drivers/net/wan/hdlc_cisco.c --- a/drivers/net/wan/hdlc_cisco.c~cisco_ioctl-initialise-header_cache_update +++ a/drivers/net/wan/hdlc_cisco.c @@ -366,6 +366,7 @@ static int cisco_ioctl(struct net_device dev->hard_start_xmit = hdlc->xmit; dev->hard_header = cisco_hard_header; dev->hard_header_cache = NULL; + dev->header_cache_update = NULL; dev->type = ARPHRD_CISCO; dev->flags = IFF_POINTOPOINT | IFF_NOARP; dev->addr_len = 0; _ - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
