7zip: Be precise about SFX data types

Use desired data types: Offsets in files are (u)int64_t, sizes in memory
are (s)size_t. Use signedness when needed or specified by APIs.

Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>

diff --git a/libarchive/archive_read_support_format_7zip.c b/libarchive/archive_read_support_format_7zip.c
index 54066ba7e8f208acb7ba8e06dcdd9fc7d30628db..9aa9d952b6ba6d9d6cca39ced90f4e673249f221 100644 (file)
--- a/libarchive/archive_read_support_format_7zip.c
+++ b/libarchive/archive_read_support_format_7zip.c
@@ -450,8 +450,8 @@ static ssize_t      read_stream(struct archive_read *, const void **, size_t,
 static int     seek_pack(struct archive_read *);
 static int64_t skip_stream(struct archive_read *, size_t);
 static int     get_data_offset(struct archive_read *, int64_t *);
-static int     get_pe_sfx_offset(struct archive_read *, ssize_t *);
-static int     get_elf_sfx_offset(struct archive_read *, ssize_t *);
+static int     get_pe_sfx_offset(struct archive_read *, int64_t *);
+static int     get_elf_sfx_offset(struct archive_read *, int64_t *);
 static int     slurp_central_directory(struct archive_read *, struct _7zip *,
                    struct _7z_header_info *);
 static int     setup_decode_folder(struct archive_read *, struct _7z_folder *,
@@ -533,10 +533,8 @@ static int
 get_data_offset(struct archive_read *a, int64_t *data_offset)
 {
        const unsigned char *p;
-       ssize_t min_addr;
-       ssize_t offset;
-       ssize_t window;
-       int r;
+       int64_t offset, sfx_offset;
+       int r, window;
 
        if ((p = __archive_read_ahead(a, 6, NULL)) == NULL)
                goto fail;
@@ -557,17 +555,17 @@ get_data_offset(struct archive_read *a, int64_t *data_offset)
         * thus a performance difference between the two is expected. 
         */
        if ((p[0] == 'M' && p[1] == 'Z'))
-               r = get_pe_sfx_offset(a, &min_addr);
+               r = get_pe_sfx_offset(a, &sfx_offset);
        else if (memcmp(p, "\x7F\x45LF", 4) == 0)
-               r = get_elf_sfx_offset(a, &min_addr);
+               r = get_elf_sfx_offset(a, &sfx_offset);
        else
                r = ARCHIVE_FATAL;
        if (r < ARCHIVE_WARN)
                goto fail;
 
-       offset = min_addr;
+       offset = sfx_offset;
        window = 4096;
-       while (offset + window <= (min_addr + SFX_MAX_OFFSET)) {
+       while (offset + window <= (sfx_offset + SFX_MAX_OFFSET)) {
                ssize_t bytes_avail;
                const unsigned char *buff = __archive_read_ahead(a,
                                offset + window, &bytes_avail);
@@ -637,16 +635,17 @@ check_7zip_header_in_sfx(const unsigned char *p)
 }
 
 static int
-get_pe_sfx_offset(struct archive_read *a, ssize_t *minaddr)
+get_pe_sfx_offset(struct archive_read *a, int64_t *sfx_offset)
 {
        const char *h;
-       ssize_t bytes, max_offset, offset, sec_end;
-       ssize_t opt_hdr_sz, sec_cnt;
+       int64_t max_offset, offset;
+       ssize_t bytes;
+       uint16_t opt_hdr_sz, sec_cnt;
 
        /*
         * If encounter any weirdness, revert to old brute-force style search
         */
-       *minaddr = SFX_MIN_ADDR;
+       *sfx_offset = SFX_MIN_ADDR;
 
        for (;;) {
                /*
@@ -700,6 +699,8 @@ get_pe_sfx_offset(struct archive_read *a, ssize_t *minaddr)
                }
                max_offset = offset;
                while (sec_cnt > 0) {
+                       uint32_t sec_end;
+
                        sec_end = archive_le32dec(
                                      h + offset + PE_SEC_HDR_RAW_SZ_OFFSET) +
                            archive_le32dec(
@@ -710,7 +711,7 @@ get_pe_sfx_offset(struct archive_read *a, ssize_t *minaddr)
                        offset += PE_SEC_HDR_LEN;
                        sec_cnt--;
                }
-               *minaddr = max_offset;
+               *sfx_offset = max_offset;
                break;
        }
 
@@ -718,12 +719,12 @@ get_pe_sfx_offset(struct archive_read *a, ssize_t *minaddr)
 }
 
 static int
-get_elf_sfx_offset(struct archive_read *a, ssize_t *minaddr)
+get_elf_sfx_offset(struct archive_read *a, int64_t *sfx_offset)
 {
        const char *h;
        char big_endian, format_64;
        ssize_t bytes;
-       ssize_t request;
+       size_t request;
        uint64_t e_shoff, strtab_offset, strtab_size;
        uint16_t e_shentsize, e_shnum, e_shstrndx;
        uint16_t (*dec16)(const void *);
@@ -733,7 +734,7 @@ get_elf_sfx_offset(struct archive_read *a, ssize_t *minaddr)
        /*
         * If encounter any weirdness, revert to old brute-force style search
         */
-       *minaddr = SFX_MIN_ADDR;
+       *sfx_offset = SFX_MIN_ADDR;
 
        for (;;) {
                /*
@@ -785,9 +786,9 @@ get_elf_sfx_offset(struct archive_read *a, ssize_t *minaddr)
                        return (ARCHIVE_FATAL);
                }
                if (format_64) {
-                 request = (size_t)e_shnum * (size_t)e_shentsize + 0x28;
+                       request = (size_t)e_shnum * e_shentsize + 0x28;
                } else {
-                 request = (size_t)e_shnum * (size_t)e_shentsize + 0x18;
+                       request = (size_t)e_shnum * e_shentsize + 0x18;
                }
                h = __archive_read_ahead(a, request, &bytes);
                if (h == NULL) {
@@ -817,14 +818,14 @@ get_elf_sfx_offset(struct archive_read *a, ssize_t *minaddr)
                if (h == NULL) {
                        return (ARCHIVE_FATAL);
                }
-               ssize_t data_sym_offset = -1;
+               size_t data_sym_offset = strtab_size;
                for (size_t offset = 0; offset < strtab_size - 6; offset++) {
                        if (memcmp(h + offset, ".data\00", 6) == 0) {
                                data_sym_offset = offset;
                                break;
                        }
                }
-               if (data_sym_offset == -1) {
+               if (data_sym_offset == strtab_size) {
                        break;
                }
 
@@ -834,15 +835,17 @@ get_elf_sfx_offset(struct archive_read *a, ssize_t *minaddr)
                if (__archive_read_seek(a, e_shoff, SEEK_SET) < 0) {
                        return (ARCHIVE_FATAL);
                }
-               h = __archive_read_ahead(a, (size_t)e_shnum * (size_t)e_shentsize, NULL);
+               h = __archive_read_ahead(a, (size_t)e_shnum * e_shentsize, NULL);
                if (h == NULL) {
                        return (ARCHIVE_FATAL);
                }
-               ssize_t sec_tbl_offset = 0, name_offset;
+               size_t sec_tbl_offset = 0;
                while (e_shnum > 0) {
+                       uint32_t name_offset;
+
                        name_offset = (*dec32)(h + sec_tbl_offset);
                        if (name_offset == data_sym_offset) {
-                               uint64_t sel_offset;
+                               int64_t sel_offset;
 
                                if (format_64) {
                                        sel_offset = (*dec64)(
@@ -851,9 +854,8 @@ get_elf_sfx_offset(struct archive_read *a, ssize_t *minaddr)
                                        sel_offset = (*dec32)(
                                            h + sec_tbl_offset + 0x10);
                                }
-                               if (sel_offset > SSIZE_MAX)
-                                       break;
-                               *minaddr = (ssize_t)sel_offset;
+                               if (sel_offset >= 0)
+                                       *sfx_offset = sel_offset;
                                break;
                        }
                        sec_tbl_offset += e_shentsize;
@@ -3228,7 +3230,7 @@ slurp_central_directory(struct archive_read *a, struct _7zip *zip,
        if ((p = __archive_read_ahead(a, 32, &bytes_avail)) == NULL)
                return (ARCHIVE_FATAL);
 
-       zip->seek_base = data_offset + 32;
+       zip->seek_base = (uint64_t)data_offset + 32;
 
        if (memcmp(p, _7ZIP_SIGNATURE, 6) != 0) {
                archive_set_error(&a->archive, -1, "Not 7-Zip archive file");