AW: AW: PROBLEM: Kernel Oops in UDP stack

From: Marcel Hellwig
Date: Wed Aug 01 2018 - 06:35:58 EST


>> [<c0228adc>] (udp_recvmsg+0x284/0x33c) from [<c02306e0>] (inet_recvmsg+0x38/0x4c): net/ipv4/udp.c:1234
>
> sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
>
>Unaligned access trap (virtual address c14fe63a), so either sin or ip_hdr(skb) are not on a 32bit alignment
>
>Can you produce the disassembly of the trapping instruction ?

https://gist.github.com/hellow554/6b11c6c0827d5db80a7e66f71f5636ff#file-net_uipv4_udp-lst-L1892-L1895

sin->sin_addr.s_addr = ip_hdr(skb)->saddr;
c0228ad8: e5943080 ldr r3, [r4, #128] ; 0x80
c0228adc: e593300c ldr r3, [r3, #12]
c0228ae0: e5823004 str r3, [r2, #4]


Mit freundlichen GrÃÃen / With kind regards

Marcel Hellwig
B. Sc. Informatik
Entwickler

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