aboutsummaryrefslogtreecommitdiffstats
path: root/drivers
diff options
context:
space:
mode:
authorPhilippe De Muyter <phdm@macqel.be>2005-11-08 12:40:26 -0500
committerDavid S. Miller <davem@davemloft.net>2005-11-08 12:40:26 -0500
commit6722e78c90054101e6797d5944cdc81af9897a0a (patch)
tree853b2618ecf9ec9e051ad49f1cca64d3854544a9 /drivers
parentdc8103f25fd7cfac2c2b295f33edc10f255b4c80 (diff)
[PPP]: handle misaligned accesses
From: "Philippe De Muyter" <phdm@macqel.be> This patch avoids ppp-generated kernel crashes on machines where unaligned accesses are forbidden (ie: m68000), by fixing ppp alignment setting for reused skb's. Signed-off-by: Philippe De Muyter <phdm@macqel.be> Cc: "David S. Miller" <davem@davemloft.net> Cc: Paul Mackerras <paulus@samba.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers')
-rw-r--r--drivers/net/ppp_async.c17
1 files changed, 14 insertions, 3 deletions
diff --git a/drivers/net/ppp_async.c b/drivers/net/ppp_async.c
index 59e8183c639e..400f652282d7 100644
--- a/drivers/net/ppp_async.c
+++ b/drivers/net/ppp_async.c
@@ -31,6 +31,7 @@
31#include <linux/spinlock.h> 31#include <linux/spinlock.h>
32#include <linux/init.h> 32#include <linux/init.h>
33#include <asm/uaccess.h> 33#include <asm/uaccess.h>
34#include <asm/string.h>
34 35
35#define PPP_VERSION "2.4.2" 36#define PPP_VERSION "2.4.2"
36 37
@@ -835,8 +836,11 @@ process_input_packet(struct asyncppp *ap)
835 err: 836 err:
836 /* frame had an error, remember that, reset SC_TOSS & SC_ESCAPE */ 837 /* frame had an error, remember that, reset SC_TOSS & SC_ESCAPE */
837 ap->state = SC_PREV_ERROR; 838 ap->state = SC_PREV_ERROR;
838 if (skb) 839 if (skb) {
840 /* make skb appear as freshly allocated */
839 skb_trim(skb, 0); 841 skb_trim(skb, 0);
842 skb_reserve(skb, - skb_headroom(skb));
843 }
840} 844}
841 845
842/* Called when the tty driver has data for us. Runs parallel with the 846/* Called when the tty driver has data for us. Runs parallel with the
@@ -889,10 +893,17 @@ ppp_async_input(struct asyncppp *ap, const unsigned char *buf,
889 skb = dev_alloc_skb(ap->mru + PPP_HDRLEN + 2); 893 skb = dev_alloc_skb(ap->mru + PPP_HDRLEN + 2);
890 if (skb == 0) 894 if (skb == 0)
891 goto nomem; 895 goto nomem;
892 /* Try to get the payload 4-byte aligned */ 896 ap->rpkt = skb;
897 }
898 if (skb->len == 0) {
899 /* Try to get the payload 4-byte aligned.
900 * This should match the
901 * PPP_ALLSTATIONS/PPP_UI/compressed tests in
902 * process_input_packet, but we do not have
903 * enough chars here to test buf[1] and buf[2].
904 */
893 if (buf[0] != PPP_ALLSTATIONS) 905 if (buf[0] != PPP_ALLSTATIONS)
894 skb_reserve(skb, 2 + (buf[0] & 1)); 906 skb_reserve(skb, 2 + (buf[0] & 1));
895 ap->rpkt = skb;
896 } 907 }
897 if (n > skb_tailroom(skb)) { 908 if (n > skb_tailroom(skb)) {
898 /* packet overflowed MRU */ 909 /* packet overflowed MRU */