Author: sobomax Date: Fri Nov 23 22:36:56 2018 New Revision: 340857 URL: https://svnweb.freebsd.org/changeset/base/340857
Log: Nuke out buffer overflow safety marker code, it duplicates similar code in the malloc()/free() as well as having potential of softening the handling in case error is detected down to a mere warning as compared to hard panic in free(). Submitted by: tsoome Differential Revision: https://reviews.freebsd.org/D18299 Modified: head/stand/common/bcache.c Modified: head/stand/common/bcache.c ============================================================================== --- head/stand/common/bcache.c Fri Nov 23 22:24:59 2018 (r340856) +++ head/stand/common/bcache.c Fri Nov 23 22:36:56 2018 (r340857) @@ -86,7 +86,6 @@ static u_int bcache_rablks; ((bc)->bcache_ctl[BHASH((bc), (blkno))].bc_blkno != (blkno)) #define BCACHE_READAHEAD 256 #define BCACHE_MINREADAHEAD 32 -#define BCACHE_MARKER 0xdeadbeef static void bcache_invalidate(struct bcache *bc, daddr_t blkno); static void bcache_insert(struct bcache *bc, daddr_t blkno); @@ -123,7 +122,6 @@ bcache_allocate(void) u_int i; struct bcache *bc = malloc(sizeof (struct bcache)); int disks = bcache_numdev; - uint32_t *marker; if (disks == 0) disks = 1; /* safe guard */ @@ -142,8 +140,7 @@ bcache_allocate(void) bc->bcache_nblks = bcache_total_nblks >> i; bcache_unit_nblks = bc->bcache_nblks; - bc->bcache_data = malloc(bc->bcache_nblks * bcache_blksize + - sizeof(uint32_t)); + bc->bcache_data = malloc(bc->bcache_nblks * bcache_blksize); if (bc->bcache_data == NULL) { /* dont error out yet. fall back to 32 blocks and try again */ bc->bcache_nblks = 32; @@ -158,9 +155,6 @@ bcache_allocate(void) errno = ENOMEM; return (NULL); } - /* Insert cache end marker. */ - marker = (uint32_t *)(bc->bcache_data + bc->bcache_nblks * bcache_blksize); - *marker = BCACHE_MARKER; /* Flush the cache */ for (i = 0; i < bc->bcache_nblks; i++) { @@ -222,15 +216,12 @@ read_strategy(void *devdata, int rw, daddr_t blk, size int result; daddr_t p_blk; caddr_t p_buf; - uint32_t *marker; if (bc == NULL) { errno = ENODEV; return (-1); } - marker = (uint32_t *)(bc->bcache_data + bc->bcache_nblks * bcache_blksize); - if (rsize != NULL) *rsize = 0; @@ -348,12 +339,6 @@ read_strategy(void *devdata, int rw, daddr_t blk, size if (size != 0) { bcopy(bc->bcache_data + (bcache_blksize * BHASH(bc, blk)), buf, size); result = 0; - } - - if (*marker != BCACHE_MARKER) { - printf("BUG: bcache corruption detected: nblks: %zu p_blk: %lu, " - "p_size: %zu, ra: %zu\n", bc->bcache_nblks, - (long unsigned)BHASH(bc, p_blk), p_size, ra); } done: _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
