Commit | Line | Data |
---|---|---|
4873188f FF |
1 | Backport of commit: |
2 | https://git.busybox.net/busybox/commit/?id=0ccf52a9fb9fa2f76eacbb6f1ef8419220557a40 | |
3 | for issue: | |
4 | https://bugs.busybox.net/show_bug.cgi?id=8821 | |
5 | ||
6 | diff --git a/archival/unzip.c b/archival/unzip.c | |
7 | index f41ab6f..b0a6ca8 100644 | |
8 | --- a/archival/unzip.c | |
9 | +++ b/archival/unzip.c | |
10 | @@ -45,6 +45,12 @@ | |
11 | #include "libbb.h" | |
12 | #include "bb_archive.h" | |
13 | ||
14 | +#if 0 | |
15 | +# define dbg(...) bb_error_msg(__VA_ARGS__) | |
16 | +#else | |
17 | +# define dbg(...) ((void)0) | |
18 | +#endif | |
19 | + | |
20 | enum { | |
21 | #if BB_BIG_ENDIAN | |
22 | ZIP_FILEHEADER_MAGIC = 0x504b0304, | |
23 | @@ -193,15 +199,17 @@ static uint32_t find_cdf_offset(void) | |
24 | unsigned char *p; | |
25 | off_t end; | |
26 | unsigned char *buf = xzalloc(PEEK_FROM_END); | |
27 | + uint32_t found; | |
28 | ||
29 | end = xlseek(zip_fd, 0, SEEK_END); | |
30 | end -= PEEK_FROM_END; | |
31 | if (end < 0) | |
32 | end = 0; | |
33 | - xlseek(zip_fd, end, SEEK_SET); | |
34 | + dbg("Looking for cdf_offset starting from 0x%"OFF_FMT"x", end); | |
35 | + xlseek(zip_fd, end, SEEK_SET); | |
36 | full_read(zip_fd, buf, PEEK_FROM_END); | |
37 | ||
38 | - cde_header.formatted.cdf_offset = BAD_CDF_OFFSET; | |
39 | + found = BAD_CDF_OFFSET; | |
40 | p = buf; | |
41 | while (p <= buf + PEEK_FROM_END - CDE_HEADER_LEN - 4) { | |
42 | if (*p != 'P') { | |
43 | @@ -220,14 +228,25 @@ static uint32_t find_cdf_offset(void) | |
44 | /* | |
45 | * I've seen .ZIP files with seemingly valid CDEs | |
46 | * where cdf_offset points past EOF - ?? | |
47 | - * Ignore such CDEs: | |
48 | + * This check ignores such CDEs: | |
49 | */ | |
50 | - if (cde_header.formatted.cdf_offset < end + (p - buf)) | |
51 | - break; | |
52 | - cde_header.formatted.cdf_offset = BAD_CDF_OFFSET; | |
53 | + if (cde_header.formatted.cdf_offset < end + (p - buf)) { | |
54 | + found = cde_header.formatted.cdf_offset; | |
55 | + dbg("Possible cdf_offset:0x%x at 0x%"OFF_FMT"x", | |
56 | + (unsigned)found, end + (p-3 - buf)); | |
57 | + dbg(" cdf_offset+cdf_size:0x%x", | |
58 | + (unsigned)(found + SWAP_LE32(cde_header.formatted.cdf_size))); | |
59 | + /* | |
60 | + * We do not "break" here because only the last CDE is valid. | |
61 | + * I've seen a .zip archive which contained a .zip file, | |
62 | + * uncompressed, and taking the first CDE was using | |
63 | + * the CDE inside that file! | |
64 | + */ | |
65 | + } | |
66 | } | |
67 | free(buf); | |
68 | - return cde_header.formatted.cdf_offset; | |
69 | + dbg("Found cdf_offset:0x%x", (unsigned)found); | |
70 | + return found; | |
71 | }; | |
72 | ||
73 | static uint32_t read_next_cdf(uint32_t cdf_offset, cdf_header_t *cdf_ptr) | |
74 | @@ -240,9 +259,13 @@ static uint32_t read_next_cdf(uint32_t cdf_offset, cdf_header_t *cdf_ptr) | |
75 | cdf_offset = find_cdf_offset(); | |
76 | ||
77 | if (cdf_offset != BAD_CDF_OFFSET) { | |
78 | + dbg("Reading CDF at 0x%x", (unsigned)cdf_offset); | |
79 | xlseek(zip_fd, cdf_offset + 4, SEEK_SET); | |
80 | xread(zip_fd, cdf_ptr->raw, CDF_HEADER_LEN); | |
81 | FIX_ENDIANNESS_CDF(*cdf_ptr); | |
82 | + dbg("file_name_length:%u", (unsigned)cdf_ptr->formatted.file_name_length); | |
83 | + dbg("extra_field_length:%u", (unsigned)cdf_ptr->formatted.extra_field_length); | |
84 | + dbg("file_comment_length:%u", (unsigned)cdf_ptr->formatted.file_comment_length); | |
85 | cdf_offset += 4 + CDF_HEADER_LEN | |
86 | + cdf_ptr->formatted.file_name_length | |
87 | + cdf_ptr->formatted.extra_field_length | |
88 | @@ -532,11 +555,14 @@ int unzip_main(int argc, char **argv) | |
89 | /* Check magic number */ | |
90 | xread(zip_fd, &magic, 4); | |
91 | /* Central directory? It's at the end, so exit */ | |
92 | - if (magic == ZIP_CDF_MAGIC) | |
93 | + if (magic == ZIP_CDF_MAGIC) { | |
94 | + dbg("got ZIP_CDF_MAGIC"); | |
95 | break; | |
96 | + } | |
97 | #if ENABLE_DESKTOP | |
98 | /* Data descriptor? It was a streaming file, go on */ | |
99 | if (magic == ZIP_DD_MAGIC) { | |
100 | + dbg("got ZIP_DD_MAGIC"); | |
101 | /* skip over duplicate crc32, cmpsize and ucmpsize */ | |
102 | unzip_skip(3 * 4); | |
103 | continue; | |
104 | @@ -544,6 +570,7 @@ int unzip_main(int argc, char **argv) | |
105 | #endif | |
106 | if (magic != ZIP_FILEHEADER_MAGIC) | |
107 | bb_error_msg_and_die("invalid zip magic %08X", (int)magic); | |
108 | + dbg("got ZIP_FILEHEADER_MAGIC"); | |
109 | ||
110 | /* Read the file header */ | |
111 | xread(zip_fd, zip_header.raw, ZIP_HEADER_LEN); | |
112 |