fix neg reads

radareorg · Feb 2, 2023 · 28ddd4a · 28ddd4a
1 parent c96eaef
commit 28ddd4a
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Showing 2 changed files with 12 additions and 10 deletions.
diff --git a/libr/core/casm.c b/libr/core/casm.c
@@ -508,7 +508,7 @@ R_API RList *r_core_asm_bwdisassemble(RCore *core, ut64 addr, int n, int len) {
  free (buf);
  return NULL;
  }
- if (!r_io_read_at (core->io, addr - (len / addrbytes), buf, len)) {
+ if (!r_io_read_at (core->io, addr - len / addrbytes, buf, len)) {
  r_list_free (hits);
  free (buf);
  return NULL;

diff --git a/libr/core/cmd_print.c b/libr/core/cmd_print.c
@@ -5795,22 +5795,21 @@ static int cmd_print(void *data, const char *input) {
  r_print_init_rowoffsets (core->print);
  tmpseek = core->offset;
  l = len = core->blocksize;
+ bool must_read = false;
  if (input[0] && input[1]) {
  int idx = (input[0] == 'h')? 2: 1;
  const char *p = strchr (input + idx, ' ');
  if (!p) {
  p = strchr (input, '-');
- if (p) {
- p--;
- }
  }
  if (p) {
- l = (int) r_num_math (core->num, p + 1);
+ l = (int) r_num_math (core->num, p);
  /* except disasm and memoryfmt (pd, pm) and overlay (po) */
  if (input[0] != 'd' && input[0] != 't' && input[0] != 'D' && input[0] != 'm' &&
  input[0] != 'a' && input[0] != 'f' && input[0] != 'i' &&
  input[0] != 'I' && input[0] != 'o') {
  if (l < 0) {
+ must_read = true;
  off = core->offset + l;
  len = l = -l;
  } else {
@@ -5822,34 +5821,37 @@ static int cmd_print(void *data, const char *input) {
  }
  }
  } else {
- len = l;
  if (l < 0) {
+ must_read = true;
  off = core->offset + l;
+ len = -len;
+ } else {
+ len = l;
  }
  }
  }
  }
  int olen = len;
  at = off;
- if (len < 0) {
- len = -len;
- }
  const int padding = core->blocksize + 256;
  block = malloc (len + padding);
  // if (!block) die
  if (block) {
- if (len > core->blocksize) {
+ if (!must_read && len > core->blocksize) {
  memset (block, core->io->Oxff, len + padding);
  r_io_read_at (core->io, off, block, len);
  } else {
  block = calloc (1, len + padding);
  if (block) {
+ ut64 oo = core->offset;
+ core->offset = at;
  r_core_block_read (core);
  memset (block, core->io->Oxff, len + padding);
  r_io_read_at (core->io, off, block, len);
  if (off == core->offset) {
  memcpy (block, core->block, R_MIN (core->blocksize, len));
  }
+ core->offset = oo;
  }
  }
  } else {