+ fs-proc-kcorec-clear-ret-value-in-read_kcore_iter-after-successful-iov_iter_zero.patch added to mm-hotfixes-unstable branch

+ fs-proc-kcorec-clear-ret-value-in-read_kcore_iter-after-successful-iov_iter_zero.patch added to mm-hotfixes-unstable branch

[Andrew Morton]

The patch titled
     Subject: fs/proc/kcore.c: clear ret value in read_kcore_iter after successful iov_iter_zero
has been added to the -mm mm-hotfixes-unstable branch.  Its filename is
     fs-proc-kcorec-clear-ret-value-in-read_kcore_iter-after-successful-iov_iter_zero.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/fs-proc-kcorec-clear-ret-value-in-read_kcore_iter-after-successful-iov_iter_zero.patch

This patch will later appear in the mm-hotfixes-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Jiri Olsa <jolsa@kernel.org>
Subject: fs/proc/kcore.c: clear ret value in read_kcore_iter after successful iov_iter_zero
Date: Fri, 22 Nov 2024 00:11:18 +0100

If iov_iter_zero succeeds after failed copy_from_kernel_nofault, we need
to reset the ret value to zero otherwise it will be returned as final
return value of read_kcore_iter.

This fixes objdump -d dump over /proc/kcore for me.

Link: https://lkml.kernel.org/r/20241121231118.3212000-1-jolsa@kernel.org
Fixes: 3d5854d75e31 ("fs/proc/kcore.c: allow translation of physical memory addresses")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: <hca@linux.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/proc/kcore.c |    1 +
 1 file changed, 1 insertion(+)

--- a/fs/proc/kcore.c~fs-proc-kcorec-clear-ret-value-in-read_kcore_iter-after-successful-iov_iter_zero
+++ a/fs/proc/kcore.c
@@ -600,6 +600,7 @@ static ssize_t read_kcore_iter(struct ki
 					ret = -EFAULT;
 					goto out;
 				}
+				ret = 0;
 			/*
 			 * We know the bounce buffer is safe to copy from, so
 			 * use _copy_to_iter() directly.
_

Patches currently in -mm which might be from jolsa@kernel.org are

fs-proc-kcorec-clear-ret-value-in-read_kcore_iter-after-successful-iov_iter_zero.patch