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| author | Denys Vlasenko | 2014-02-19 14:17:11 +0100 |
|---|---|---|
| committer | Denys Vlasenko | 2014-02-19 14:17:11 +0100 |
| commit | ffc3a93d0dbf4ac887f528c0495cd586a092d88f (patch) | |
| tree | 6d8d51a7cbd435d3e2a22a34f620770968c6c2b6 | |
| parent | 50e4cc29f56b5401579cddaf42d0404320b9efa7 (diff) | |
| download | busybox-ffc3a93d0dbf4ac887f528c0495cd586a092d88f.zip busybox-ffc3a93d0dbf4ac887f528c0495cd586a092d88f.tar.gz | |
udhcpc: fix BPF filter. Hopefully fixes the root cause of 4598 and 6746
Use a *signed* large positive value in BPF filter to indicate success.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
| -rw-r--r-- | networking/udhcp/d6_dhcpc.c | 2 | ||||
| -rw-r--r-- | networking/udhcp/dhcpc.c | 7 |
2 files changed, 5 insertions, 4 deletions
diff --git a/networking/udhcp/d6_dhcpc.c b/networking/udhcp/d6_dhcpc.c index b0f0798..044f046 100644 --- a/networking/udhcp/d6_dhcpc.c +++ b/networking/udhcp/d6_dhcpc.c @@ -711,7 +711,7 @@ static int d6_raw_socket(int ifindex) /* jump to L3 if udp dport is CLIENT_PORT6, else to L4 */ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 68, 0, 1), /* L3: accept packet */ - BPF_STMT(BPF_RET|BPF_K, 0xffffffff), + BPF_STMT(BPF_RET|BPF_K, 0x7fffffff), /* L4: discard packet */ BPF_STMT(BPF_RET|BPF_K, 0), }; diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c index bdb1e2b..25f18b3 100644 --- a/networking/udhcp/dhcpc.c +++ b/networking/udhcp/dhcpc.c @@ -1025,9 +1025,10 @@ static int udhcp_raw_socket(int ifindex) BPF_STMT(BPF_LD|BPF_H|BPF_IND, 2), /* jump to L3 if udp dport is CLIENT_PORT, else to L4 */ BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, 68, 0, 1), - /* L3: accept packet */ - BPF_STMT(BPF_RET|BPF_K, 0xffffffff), - /* L4: discard packet */ + /* L3: accept packet ("accept 0x7fffffff bytes") */ + /* Accepting 0xffffffff works too but kernel 2.6.19 is buggy */ + BPF_STMT(BPF_RET|BPF_K, 0x7fffffff), + /* L4: discard packet ("accept zero bytes") */ BPF_STMT(BPF_RET|BPF_K, 0), }; static const struct sock_fprog filter_prog = { |