Inspired by a patch from [Justin][1] I took a closer look at kdb_read(). Despite Justin's patch being a (correct) one-line manipulation it was a tough patch to review because the surrounding code was hard to read and it looked like there were unfixed problems. This series isn't enough to make kdb_read() beautiful but it does make it shorter, easier to reason about and fixes two buffer overflows and a screen redraw problem! [1]: https://lore.kernel.org/all/20240403-strncpy-kernel-debug-kdb-kdb_io-c-v1-1-7f78a08e9ff4@xxxxxxxxxx/ Signed-off-by: Daniel Thompson <daniel.thompson@xxxxxxxxxx> --- Changes in v3: - Collected tags from v2 - Added comment to describe the hidden depths of kdb_position_cursor() (thanks Doug) - Fixed a couple of typos in the patch descriptions (thanks Doug) - Link to v2: https://lore.kernel.org/r/20240422-kgdb_read_refactor-v2-0-ed51f7d145fe@xxxxxxxxxx Changes in v2: - No code changes! - I belatedly realized that one of the cleanups actually fixed a buffer overflow so there are changes to Cc: (to add stable@...) and to one of the patch descriptions. - Link to v1: https://lore.kernel.org/r/20240416-kgdb_read_refactor-v1-0-b18c2d01076d@xxxxxxxxxx --- Daniel Thompson (7): kdb: Fix buffer overflow during tab-complete kdb: Use format-strings rather than '\0' injection in kdb_read() kdb: Fix console handling when editing and tab-completing commands kdb: Merge identical case statements in kdb_read() kdb: Use format-specifiers rather than memset() for padding in kdb_read() kdb: Replace double memcpy() with memmove() in kdb_read() kdb: Simplify management of tmpbuffer in kdb_read() kernel/debug/kdb/kdb_io.c | 153 +++++++++++++++++++++++----------------------- 1 file changed, 78 insertions(+), 75 deletions(-) --- base-commit: dccce9b8780618986962ba37c373668bcf426866 change-id: 20240415-kgdb_read_refactor-2ea2dfc15dbb Best regards, -- Daniel Thompson <daniel.thompson@xxxxxxxxxx>
