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: aac51f09d96a ("[PATCH] w100fb: Rewrite for platform independence") Cc: Richard Purdie rpurdie@rpsys.net Cc: Antonino Daplas adaplas@pol.net Cc: Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com Cc: stable@vger.kernel.org # v2.6.14+ Signed-off-by: Christophe JAILLET christophe.jaillet@wanadoo.fr --- v2: - Add Cc: tags - Reword the commit message to give the names of the functions that allocate and free the memory. These functions are called from the suspend and resume function. --- drivers/video/fbdev/w100fb.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/video/fbdev/w100fb.c b/drivers/video/fbdev/w100fb.c index 2d6e2738b792..d96ab28f8ce4 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; } }
Hi Christophe On Wed, May 06, 2020 at 08:19:02PM +0200, Christophe JAILLET wrote:
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: aac51f09d96a ("[PATCH] w100fb: Rewrite for platform independence") Cc: Richard Purdie rpurdie@rpsys.net Cc: Antonino Daplas adaplas@pol.net Cc: Bartlomiej Zolnierkiewicz b.zolnierkie@samsung.com Cc: stable@vger.kernel.org # v2.6.14+ Signed-off-by: Christophe JAILLET christophe.jaillet@wanadoo.fr
Thanks for the quick v2. Applied to drm-misc-next.
Sam
v2: - Add Cc: tags - Reword the commit message to give the names of the functions that allocate and free the memory. These functions are called from the suspend and resume function.
drivers/video/fbdev/w100fb.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/video/fbdev/w100fb.c b/drivers/video/fbdev/w100fb.c index 2d6e2738b792..d96ab28f8ce4 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;@@ -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;} -- 2.25.1
linux-stable-mirror@lists.linaro.org
-
Christophe JAILLET -
Sam Ravnborg