staging: fbtft: fix potential memory leak in fbtft_framebuffer_alloc()

After commit 56c134f7f1b5 ("fbdev: Track deferred-I/O pages in pageref
struct"), fb_deferred_io_init() allocates memory for info->pagerefs as
well as return an error code on failure. However the error code is
ignored here and the memory allocated could leak because of not calling
fb_deferred_io_cleanup() on the error path.

Fix them by adding the cleanup function on the error path, and handling
the error code returned by fb_deferred_io_init().

Fixes: 56c134f7f1b5 ("fbdev: Track deferred-I/O pages in pageref struct")
Signed-off-by: Abdun Nihaal <abdun.nihaal@gmail.com>
Reviewed-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/fd2be49cfef72799f17a96d01a4c6b92770cda7d.1751207100.git.abdun.nihaal@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/fbtft/fbtft-core.c b/drivers/staging/fbtft/fbtft-core.c
index 39bced40006501c615b7b8b47c9d8e0061c4b448..d920164e7710b1927f7b3da2064bbde11467bd18 100644 (file)
--- a/drivers/staging/fbtft/fbtft-core.c
+++ b/drivers/staging/fbtft/fbtft-core.c
@@ -612,7 +612,8 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
        info->fix.line_length =    width * bpp / 8;
        info->fix.accel =          FB_ACCEL_NONE;
        info->fix.smem_len =       vmem_size;
-       fb_deferred_io_init(info);
+       if (fb_deferred_io_init(info))
+               goto release_framebuf;
 
        info->var.rotate =         pdata->rotate;
        info->var.xres =           width;
@@ -652,7 +653,7 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
        if (par->gamma.curves && gamma) {
                if (fbtft_gamma_parse_str(par, par->gamma.curves, gamma,
                                          strlen(gamma)))
-                       goto release_framebuf;
+                       goto cleanup_deferred;
        }
 
        /* Transmit buffer */
@@ -669,7 +670,7 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
        if (txbuflen > 0) {
                txbuf = devm_kzalloc(par->info->device, txbuflen, GFP_KERNEL);
                if (!txbuf)
-                       goto release_framebuf;
+                       goto cleanup_deferred;
                par->txbuf.buf = txbuf;
                par->txbuf.len = txbuflen;
        }
@@ -691,6 +692,8 @@ struct fb_info *fbtft_framebuffer_alloc(struct fbtft_display *display,
 
        return info;
 
+cleanup_deferred:
+       fb_deferred_io_cleanup(info);
 release_framebuf:
        fb_deferred_io_cleanup(info);
        framebuffer_release(info);