mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-04-06 06:43:13 -04:00
6d07bee10e
If copy_from_user() fails, write() currently returns -EFAULT, but any partially written data leaves the TX FIFO in an inconsistent state. Subsequent write() calls then fail with "transmit length mismatch" errors. Once partial data is written to the hardware FIFO, it cannot be removed without a TX reset. Commitc6e8d85faf("staging: axis-fifo: Remove hardware resets for user errors") removed a full FIFO reset for this case, which fixed a potential RX data loss, but introduced this TX issue. Fix this by introducing a bounce buffer: copy the full packet from userspace first, and write to the hardware FIFO only if the copy was successful. Fixes:c6e8d85faf("staging: axis-fifo: Remove hardware resets for user errors") Cc: stable@vger.kernel.org Signed-off-by: Ovidiu Panait <ovidiu.panait.oss@gmail.com> Link: https://lore.kernel.org/r/20250912101322.1282507-1-ovidiu.panait.oss@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>