diff options
| -rw-r--r-- | gdb/ChangeLog | 11 | ||||
| -rw-r--r-- | gdb/breakpoint.c | 21 | ||||
| -rw-r--r-- | gdb/m32r-tdep.c | 3 | ||||
| -rw-r--r-- | gdb/mem-break.c | 17 |
4 files changed, 43 insertions, 9 deletions
diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 1a755081158..875d6757d49 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,14 @@ +2012-03-15 Joel Brobecker <brobecker@adacore.com> + + * breakpoint.c (breakpoint_xfer_memory): Add assertion. + Update function description. + (insert_bp_location): Do not wipe bl->target_info out. + * mem-break.c: #include "gdb_string.h". + (default_memory_insert_breakpoint): Do not call target_read_memory + with a pointer to the breakpoint's shadow_contents buffer. Use + a local buffer instead. + * m32r-tdep.c (m32r_memory_insert_breakpoint): Ditto. + 2012-03-15 Tom Tromey <tromey@redhat.com> * NEWS: Mention "info vtbl", not "info vtable". diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c index d35704d3b4d..debf2b20122 100644 --- a/gdb/breakpoint.c +++ b/gdb/breakpoint.c @@ -1318,6 +1318,10 @@ bp_location_has_shadow (struct bp_location *bl) /* Update BUF, which is LEN bytes read from the target address MEMADDR, by replacing any memory breakpoints with their shadowed contents. + If READBUF is not NULL, this buffer must not overlap with any of + the breakpoint location's shadow_contents buffers. Otherwise, + a failed assertion internal error will be raised. + The range of shadowed area by each bp_location is: bl->address - bp_location_placed_address_before_address_max up to bl->address + bp_location_shadow_len_after_address_max @@ -1446,6 +1450,12 @@ breakpoint_xfer_memory (gdb_byte *readbuf, gdb_byte *writebuf, if (readbuf != NULL) { + /* Verify that the readbuf buffer does not overlap with + the shadow_contents buffer. */ + gdb_assert (bl->target_info.shadow_contents >= readbuf + len + || readbuf >= (bl->target_info.shadow_contents + + bl->target_info.shadow_len)); + /* Update the read buffer with this inserted breakpoint's shadow. */ memcpy (readbuf + bp_addr - memaddr, @@ -2082,8 +2092,15 @@ insert_bp_location (struct bp_location *bl, if (!should_be_inserted (bl) || (bl->inserted && !bl->needs_update)) return 0; - /* Initialize the target-specific information. */ - memset (&bl->target_info, 0, sizeof (bl->target_info)); + /* Note we don't initialize bl->target_info, as that wipes out + the breakpoint location's shadow_contents if the breakpoint + is still inserted at that location. This in turn breaks + target_read_memory which depends on these buffers when + a memory read is requested at the breakpoint location: + Once the target_info has been wiped, we fail to see that + we have a breakpoint inserted at that address and thus + read the breakpoint instead of returning the data saved in + the breakpoint location's shadow contents. */ bl->target_info.placed_address = bl->address; bl->target_info.placed_address_space = bl->pspace->aspace; bl->target_info.length = bl->length; diff --git a/gdb/m32r-tdep.c b/gdb/m32r-tdep.c index 72872bdb342..d504eb38359 100644 --- a/gdb/m32r-tdep.c +++ b/gdb/m32r-tdep.c @@ -85,7 +85,7 @@ m32r_memory_insert_breakpoint (struct gdbarch *gdbarch, CORE_ADDR addr = bp_tgt->placed_address; int val; gdb_byte buf[4]; - gdb_byte *contents_cache = bp_tgt->shadow_contents; + gdb_byte contents_cache[4]; gdb_byte bp_entry[] = { 0x10, 0xf1 }; /* dpt */ /* Save the memory contents. */ @@ -93,6 +93,7 @@ m32r_memory_insert_breakpoint (struct gdbarch *gdbarch, if (val != 0) return val; /* return error */ + memcpy (bp_tgt->shadow_contents, contents_cache, 4); bp_tgt->placed_size = bp_tgt->shadow_len = 4; /* Determine appropriate breakpoint contents and size for this address. */ diff --git a/gdb/mem-break.c b/gdb/mem-break.c index 7d0e3f1b3cc..bd34fb2df14 100644 --- a/gdb/mem-break.c +++ b/gdb/mem-break.c @@ -29,6 +29,7 @@ #include "breakpoint.h" #include "inferior.h" #include "target.h" +#include "gdb_string.h" /* Insert a breakpoint on targets that don't have any better @@ -46,6 +47,7 @@ default_memory_insert_breakpoint (struct gdbarch *gdbarch, { int val; const unsigned char *bp; + gdb_byte *readbuf; /* Determine appropriate breakpoint contents and size for this address. */ bp = gdbarch_breakpoint_from_pc @@ -53,15 +55,18 @@ default_memory_insert_breakpoint (struct gdbarch *gdbarch, if (bp == NULL) error (_("Software breakpoints not implemented for this target.")); - /* Save the memory contents. */ + /* Save the memory contents in the shadow_contents buffer and then + write the breakpoint instruction. */ bp_tgt->shadow_len = bp_tgt->placed_size; - val = target_read_memory (bp_tgt->placed_address, bp_tgt->shadow_contents, + readbuf = alloca (bp_tgt->placed_size); + val = target_read_memory (bp_tgt->placed_address, readbuf, bp_tgt->placed_size); - - /* Write the breakpoint. */ if (val == 0) - val = target_write_raw_memory (bp_tgt->placed_address, bp, - bp_tgt->placed_size); + { + memcpy (bp_tgt->shadow_contents, readbuf, bp_tgt->placed_size); + val = target_write_raw_memory (bp_tgt->placed_address, bp, + bp_tgt->placed_size); + } return val; } |