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Dereferencing this unaligned pointer can cause a kernel panic on strict-alignment architectures. Fix by using put_unaligned() instead of direct pointer dereference. Also fix incorrect buffer size calculation in fbtft_write_buf_dc() call: len * (sizeof(data_type) + offset) /* wrong: multiplies offset by len */ len * sizeof(data_type) + offset /* correct: one startbyte + len items */ Signed-off-by: suryasaimadhu --- drivers/staging/fbtft/fbtft-bus.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/staging/fbtft/fbtft-bus.c b/drivers/staging/fbtft/fbtft-bus.c index 2169f8d1d..cfcf4d7e7 100644 --- a/drivers/staging/fbtft/fbtft-bus.c +++ b/drivers/staging/fbtft/fbtft-bus.c @@ -4,6 +4,7 @@ #include #include #include "fbtft.h" +#include /***************************************************************************** * @@ -40,7 +41,7 @@ void func(struct fbtft_par *par, int len, ...) \ offset = 1; \ } \ \ - *buf = modifier((data_type)va_arg(args, unsigned int)); \ + put_unaligned(modifier((data_type)va_arg(args, unsigned int)), buf); \ ret = fbtft_write_buf_dc(par, par->buf, sizeof(data_type) + offset, \ 0); \ if (ret < 0) \ @@ -52,11 +53,13 @@ void func(struct fbtft_par *par, int len, ...) \ \ if (len) { \ i = len; \ - while (i--) \ - *buf++ = modifier((data_type)va_arg(args, \ - unsigned int)); \ + while (i--) { \ + put_unaligned(modifier((data_type)va_arg(args, \ + unsigned int)), buf); \ + buf++; \ + } \ fbtft_write_buf_dc(par, par->buf, \ - len * (sizeof(data_type) + offset), 1); \ + len * sizeof(data_type) + offset, 1); \ } \ out: \ va_end(args); \ -- 2.47.3