diff options
| author | Bohdan Tymkiv <bhdt@cypress.com> | 2019-04-16 17:28:29 +0300 |
|---|---|---|
| committer | Tomas Vanek <vanekt@fbl.cz> | 2019-06-04 21:37:41 +0100 |
| commit | eea508d9afa184684bf5a4e2788b6cd4b5fdc9ab (patch) | |
| tree | b5aaf19b1591bf78d69d90876449b0d528f83d1f /src/rtos/nuttx.c | |
| parent | 85ed41d2100ba2f451ba8ff3d75abbeb8cf10a29 (diff) | |
gdb_server: fix GDB_BUFFER_SIZE usage, fix unaligned access during bulk transfers
Currently size of the GDB buffer is 16384 bytes but it is treated as
nul-terminated string in most of the code, so effective size of the
buffer is actually 16383 bytes. OpenOCD responds with `PacketSize=3fff`
to qSupported request. Result of GDB's `m` command is encoded in hex so
each data byte uses two bytes in the buffer. As a result GDB will split
bulk read requests into chunks 0x1fff bytes each. This causes troubles
on targets (or memory regions) which support only aligned, word-sized
access (such as MMIO buffers).
Steps to reproduce (psoc6 target):
gdb> dump binary memory dump.bin 0x040320000 (0x040320000 + 65536)
OpenOCD:
Error: Failed to read memory at 0x40321ffe
Error: Failed to read memory at 0x40321000
Error: Failed to read memory at 0x40323000
Error: Failed to read memory at 0x40325ffe
Error: Failed to read memory at 0x40329ffa
Error: Failed to read memory at 0x40329ffc
Error: Failed to read memory at 0x4032bffc
Error: Failed to read memory at 0x4032dffa
Consolidate GDB_BUFFER_SIZE usage: ensure size of each buffer is
(GDB_BUFFER_SIZE + 1), add explicit comment that additional byte is used
for nul-termination. Report correct size of the buffer to GDB (0x4000)
as recommended in GDB's docummentation: `if the stub stores packets in a
NUL-terminated format, it should allow an extra byte in its buffer for
the NUL`
Checked with clang-asan, clang-analyzer, valgrind - no new errors.
Change-Id: I909e8a2c6b010c5d4a304641808d4a807a4ec18d
Signed-off-by: Bohdan Tymkiv <bhdt@cypress.com>
Reviewed-on: http://openocd.zylin.com/5109
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Diffstat (limited to 'src/rtos/nuttx.c')
| -rw-r--r-- | src/rtos/nuttx.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/src/rtos/nuttx.c b/src/rtos/nuttx.c index 61fd9aa6..8c3076e1 100644 --- a/src/rtos/nuttx.c +++ b/src/rtos/nuttx.c @@ -174,7 +174,7 @@ static int rcmd_offset(const char *cmd, const char *name) static int nuttx_thread_packet(struct connection *connection, char const *packet, int packet_size) { - char cmd[GDB_BUFFER_SIZE / 2] = ""; + char cmd[GDB_BUFFER_SIZE / 2 + 1] = ""; /* Extra byte for nul-termination */ if (!strncmp(packet, "qRcmd", 5)) { size_t len = unhexify((uint8_t *)cmd, packet + 6, sizeof(cmd)); |