On Wed, Nov 07, 2007 at 12:38:23AM +0000, brian m. carlson wrote: >tags 443880 + patch >kthxbye > >The crash in __zzip_parse_root_directory is a bus error on sparc, which >is a dead giveaway that it's an unaligned access. The problem is that >d is a zzip_disk_entry, which is required to be aligned, but zz_offset >is not guaranteed to be a multiple of sizeof(*d). > >In fact, line 456 explicitly updates zz_offset to something that is >often *not* a multiple of 4, so using a char * (fd_map, from mmap) will >result in an unaligned access. The way to solve this is to explicitly >allocate memory for d, then memcpy the data from fd_map to d, since >memcpy is guaranteed to work for memory of any alignment. > >An untested patch to do this is attached.
Thank you! >-- >brian m. carlson / brian with sandals: Houston, Texas, US >+1 713 440 7475 | http://crustytoothpaste.ath.cx/~bmc | My opinion only >a typesetting engine: http://crustytoothpaste.ath.cx/~bmc/code/thwack >OpenPGP: RSA v4 4096b 88AC E9B2 9196 305B A994 7552 F1BA 225C 0223 B187 Enrico, please test the new debian packages available at: http://people.debian.org/~anibal/zziplib/ >--- zip.c.orig 2007-11-06 23:59:24.000000000 +0000 >+++ zip.c 2007-11-07 00:35:40.000000000 +0000 >@@ -402,7 +402,10 @@ > uint16_t u_extras, u_comment, u_namlen; > > if (fd_map) >- { d = (void*)(fd_map+zz_fd_gap+zz_offset); } /* >fd_map+fd_gap==u_rootseek */ >+ { >+ d = &dirent; >+ memcpy(d, fd_map+zz_fd_gap+zz_offset, sizeof(*d)); /* >fd_map+fd_gap==u_rootseek */ >+ } > else > { > if (io->fd.seeks(fd, zz_rootseek+zz_offset, SEEK_SET) < 0)
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