CVE-2025-39847

Summary

In the Linux kernel, the following vulnerability has been resolved:

ppp: fix memory leak in pad_compress_skb

If alloc_skb() fails in pad_compress_skb(), it returns NULL without releasing the old skb. The caller does:

skb = pad_compress_skb(ppp, skb);
if (!skb)
    goto drop;

drop: kfree_skb(skb);

When pad_compress_skb() returns NULL, the reference to the old skb is lost and kfree_skb(skb) ends up doing nothing, leading to a memory leak.

Align pad_compress_skb() semantics with realloc(): only free the old skb if allocation and compression succeed. At the call site, use the new_skb variable so the original skb is not lost when pad_compress_skb() fails.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 9ca6a040f76c0b149293e430dabab446f3fc8ab7affected
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 87a35a36742df328d0badf4fbc2e56061c15846caffected
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 0b21e9cd4559102da798bdcba453b64ecd7be7eeaffected
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 1d8b354eafb8876d8bdb1bef69c7d2438aacfbe8affected
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 85c1c86a67e09143aa464e9bf09c397816772348affected
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 631fc8ab5beb9e0ec8651fb9875b9a968e7b4ae4affected
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 33a5bac5f14772730d2caf632ae97b6c2ee95044affected
LinuxLinuxb3f9b92a6ec1a9a5e4b4b36e484f2f62cc73277c < 4844123fe0b853a4982c02666cb3fd863d701d50affected
LinuxLinux2.6.15affected
LinuxLinux0 < 2.6.15unaffected
LinuxLinux5.4.299 <= 5.4.*unaffected
LinuxLinux5.10.243 <= 5.10.*unaffected
LinuxLinux5.15.192 <= 5.15.*unaffected
LinuxLinux6.1.151 <= 6.1.*unaffected
LinuxLinux6.6.105 <= 6.6.*unaffected
LinuxLinux6.12.46 <= 6.12.*unaffected
LinuxLinux6.16.6 <= 6.16.*unaffected
LinuxLinux6.17 <= *unaffected

Weaknesses

ADP Enrichment

CVE Program Container

Additional References

Additional References

References