From: Christophe JAILLET Date: Wed, 6 May 2020 18:19:02 +0000 (+0200) Subject: video: fbdev: w100fb: Fix a potential double free. X-Git-Tag: baikal/mips/sdk5.9~13559^2~13^2~6 X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=7dab0f870861b6160ae20c9dd16495b0abbb2e16;p=kernel.git video: fbdev: w100fb: Fix a potential double free. Some memory is vmalloc'ed in the 'w100fb_save_vidmem' function and freed in the 'w100fb_restore_vidmem' function. (these functions are called respectively from the 'suspend' and the 'resume' functions) However, it is also freed in the 'remove' function. In order to avoid a potential double free, set the corresponding pointer to NULL once freed in the 'w100fb_restore_vidmem' function. Fixes: 232935088a90 ("[PATCH] w100fb: Rewrite for platform independence") Cc: Richard Purdie Cc: Antonino Daplas Cc: Bartlomiej Zolnierkiewicz Cc: # v2.6.14+ Signed-off-by: Christophe JAILLET Signed-off-by: Sam Ravnborg Link: https://patchwork.freedesktop.org/patch/msgid/20200506181902.193290-1-christophe.jaillet@wanadoo.fr --- diff --git a/drivers/video/fbdev/w100fb.c b/drivers/video/fbdev/w100fb.c index 2d6e2738b792c..d96ab28f8ce4a 100644 --- a/drivers/video/fbdev/w100fb.c +++ b/drivers/video/fbdev/w100fb.c @@ -588,6 +588,7 @@ static void w100fb_restore_vidmem(struct w100fb_par *par) memsize=par->mach->mem->size; memcpy_toio(remapped_fbuf + (W100_FB_BASE-MEM_WINDOW_BASE), par->saved_extmem, memsize); vfree(par->saved_extmem); + par->saved_extmem = NULL; } if (par->saved_intmem) { memsize=MEM_INT_SIZE; @@ -596,6 +597,7 @@ static void w100fb_restore_vidmem(struct w100fb_par *par) else memcpy_toio(remapped_fbuf + (W100_FB_BASE-MEM_WINDOW_BASE), par->saved_intmem, memsize); vfree(par->saved_intmem); + par->saved_intmem = NULL; } }