sar/sadf: Make sure we can read file headers structures from older

versions

Reading the file_header or file_activity structures from a daily data
file from an older version where fewer fields were present might be a
problem as we allocate buffers based on the size of the structure from
the file. This buffer would ithen be to small for the remap_struct()
function to remap the fields to current (larger) structures.

Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>

diff --git a/sa_common.c b/sa_common.c
index 4242934293689f7a20a7a437901b359ea497bfe8..d93f9682fd4771f6aca6897c26f554de711925b3 100644 (file)
--- a/sa_common.c
+++ b/sa_common.c
@@ -1875,8 +1875,7 @@ int sa_open_read_magic(int *fd, char *dfile, struct file_magic *file_magic,
            ((file_magic->sysstat_version == 10) && (file_magic->sysstat_patchlevel >= 3))) {
                /* header_size field exists only for sysstat versions 10.3.1 and later */
                if ((file_magic->header_size <= MIN_FILE_HEADER_SIZE) ||
-                   (file_magic->header_size > MAX_FILE_HEADER_SIZE) ||
-                   ((file_magic->header_size < FILE_HEADER_SIZE) && !ignore)) {
+                   (file_magic->header_size > MAX_FILE_HEADER_SIZE)) {
 #ifdef DEBUG
                        fprintf(stderr, "%s: header_size=%u\n",
                                __FUNCTION__, file_magic->header_size);
@@ -1943,6 +1942,8 @@ void check_file_actlst(int *ifd, char *dfile, struct activity *act[], uint64_t f
        int i, j, k, p;
        struct file_activity *fal;
        void *buffer = NULL;
+       size_t bh_size = FILE_HEADER_SIZE;
+       size_t ba_size = FILE_ACTIVITY_SIZE;
 
        /* Open sa data file and read its magic structure */
        if (sa_open_read_magic(ifd, dfile, file_magic, ignore, endian_mismatch, TRUE) < 0)
@@ -1969,17 +1970,20 @@ void check_file_actlst(int *ifd, char *dfile, struct activity *act[], uint64_t f
        }
 
        /* Allocate buffer for file_header structure */
-       SREALLOC(buffer, char, file_magic->header_size);
+       if (file_magic->header_size > FILE_HEADER_SIZE) {
+               bh_size = file_magic->header_size;
+       }
+       SREALLOC(buffer, char, bh_size);
 
        /* Read sa data file standard header and allocate activity list */
        sa_fread(*ifd, buffer, (size_t) file_magic->header_size, HARD_SIZE, UEOF_STOP);
        /*
         * Data file header size (file_magic->header_size) may be greater or
         * smaller than FILE_HEADER_SIZE. Remap the fields of the file header
-        * then copy its contents to the expected  structure.
+        * then copy its contents to the expected structure.
         */
        if (remap_struct(hdr_types_nr, file_magic->hdr_types_nr, buffer,
-                        file_magic->header_size, FILE_HEADER_SIZE, file_magic->header_size) < 0)
+                        file_magic->header_size, FILE_HEADER_SIZE, bh_size) < 0)
                goto format_error;
 
        memcpy(file_hdr, buffer, FILE_HEADER_SIZE);
@@ -2014,7 +2018,11 @@ void check_file_actlst(int *ifd, char *dfile, struct activity *act[], uint64_t f
                goto format_error;
        }
 
-       SREALLOC(buffer, char, file_hdr->act_size);
+       /* Allocate buffer for file_activity structures */
+       if (file_hdr->act_size > FILE_ACTIVITY_SIZE) {
+               ba_size = file_hdr->act_size;
+       }
+       SREALLOC(buffer, char, ba_size);
        SREALLOC(*file_actlst, struct file_activity, FILE_ACTIVITY_SIZE * file_hdr->sa_act_nr);
        fal = *file_actlst;
 
@@ -2030,7 +2038,7 @@ void check_file_actlst(int *ifd, char *dfile, struct activity *act[], uint64_t f
                * then copy its contents to the expected structure.
                */
                if (remap_struct(act_types_nr, file_hdr->act_types_nr, buffer,
-                            file_hdr->act_size, FILE_ACTIVITY_SIZE, file_hdr->act_size) < 0)
+                            file_hdr->act_size, FILE_ACTIVITY_SIZE, ba_size) < 0)
                        goto format_error;
                memcpy(fal, buffer, FILE_ACTIVITY_SIZE);